JP2002086776A - Image forming device - Google Patents

Abstract

(57) Abstract: A clear full-color image can be formed without causing color unevenness or the like in each image formed in each image forming unit. An image forming area and a non-image forming area are alternately provided on an outer peripheral surface of a recording intermediate belt (15) which is endless so as to move around, and a first to a third image are provided in each image forming area. Images of different colors are sequentially formed by the recording heads 21b to 23b provided in the forming units 21 to 23, respectively. Recording head 21b of each image forming section 21-23
23b are arranged at intervals longer than the length of the image forming area along the rotation direction of the recording intermediate belt 15. Each recording head 21b-2
3b, the image forming operation is started by being pressed by the recording intermediate belt 15 in the non-image forming area in front of the image forming area, and is stopped in the non-image forming area behind the image forming area. Is done.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus capable of forming a high-quality full-color image on recording paper, which is plain paper, at a high speed.

[0002]

2. Description of the Related Art A dye thermal transfer recording method has attracted attention as an image forming method capable of forming a high quality image similar to a color photograph. In an image forming apparatus using the dye thermal transfer recording method, an endless recording intermediate belt is generally used in which end portions of a belt-shaped belt body are connected to each other in a state where they are attached to each other. The recording intermediate belt is wound around a platen drum and is moved around at a predetermined speed. A dyeing layer is transferred to an outer peripheral surface of the recording intermediate belt, and a predetermined image forming area on the dyeing layer is formed. An image is formed on the image.

Around the platen drum, a plurality of image forming units for forming images of different colors are arranged along the periphery of the platen drum, and a recording head provided in each image forming unit includes By performing an image forming operation based on an image signal while being pressed against the dyeing layer in the image forming area, images of different colors are formed. Then, a full-color image is formed on the dyeing layer by the images of different colors formed in each image forming unit.

[0004] The full-color image formed on the dyeing layer of the recording intermediate belt is transferred together with the dyeing layer onto, for example, recording paper drawn from a recording paper roll wound in a roll shape. The recording paper to which the full-color image has been transferred is cut into a predetermined size by a cutter, and is discharged outside the apparatus.

[0005]

In such an image forming apparatus, the recording intermediate belt is rotated at a predetermined speed by a high frictional force with an elastic body such as rubber provided on the outer peripheral surface of the platen drum. An image is formed by performing an image forming operation on the recording intermediate belt that is moving around in a state where the recording head of each image forming unit is pressed. For this reason, in any one of the image forming units, while an image is formed on the recording intermediate belt by the recording head, the recording head of another image forming unit is pressed against the recording intermediate belt, or When the recording head starts and stops the image forming operation, there is a possibility that a load change occurs in the recording intermediate belt. As described above, when a load change or the like occurs in the recording intermediate belt, color unevenness or the like occurs in an image formed by the recording head during the image forming operation, and a clear full-color image may not be formed.

Further, in order to move the recording intermediate belt around at a predetermined speed by the rotationally driven platen drum, it is necessary to wind the recording intermediate belt around the platen drum with high tension. However, when the recording intermediate belt is wound around the platen drum at a high tension, a large stress is applied to the recording intermediate belt, and the recording intermediate belt cannot be used stably for a long period of time. There is a problem that it needs to be replaced frequently.

Further, the intermediate recording belt is circulated at a predetermined speed by a high frictional force of an elastic body such as rubber provided on the outer peripheral surface of the platen drum. However, depending on the dimensional accuracy of the recording intermediate belt that moves around, the dimensional accuracy of the components such as the platen drum, and the assembly accuracy, the recording intermediate belt may meander and move around. When the recording intermediate belt meanders, images of different colors formed in the respective image forming units may be shifted from each other, causing color unevenness or the like.

Further, the full-color image formed on the recording intermediate belt is transferred to recording paper pulled out from a recording paper roll, and then the recording paper is peeled off from the recording intermediate belt, and the peeled recording paper is removed by a cutter. It is designed to be cut into a predetermined size. The recording paper is usually separated from the recording intermediate belt by being conveyed in a direction different from the conveyance direction of the recording intermediate belt.
However, in such a configuration in which the conveyance direction of the recording intermediate belt and the conveyance direction of the recording paper are made different from each other to separate the recording paper from the recording intermediate belt, the recording paper on which the full-color image has been transferred is removed from the recording intermediate belt. There is a possibility that it cannot be reliably peeled.

Further, the recording paper peeled off from the recording intermediate belt is cut by a cutter. When the cutter comes into contact with the recording paper, a load fluctuation occurs on the recording paper, and the load fluctuation may be transmitted to the recording intermediate belt. There is. Also in this case, there is a possibility that color unevenness or the like may occur in an image formed on the recording intermediate belt in each image forming unit.

The present invention has been made to solve such a problem, and an object of the present invention is to form a clear image without the risk of causing color unevenness or the like in an image formed on a recording intermediate belt. An object of the present invention is to provide an image forming apparatus.

Another object of the present invention is to provide an image forming apparatus in which the tension applied to the recording intermediate belt is small and the recording intermediate belt can be used stably for a long period of time.

Still another object of the present invention is to provide an image forming apparatus capable of suppressing the meandering of the recording intermediate belt and allowing the recording intermediate belt to run stably.

Still another object of the present invention is to enable the recording paper to be reliably peeled off from the recording intermediate belt.
There is no possibility that the load fluctuation of the recording paper that occurs when the recording paper is cut by a cutter or the like is transmitted to the recording intermediate belt, and therefore, there is no possibility that the image formed on the recording intermediate belt has color unevenness or the like. It is to provide a device.

[0014]

An image forming apparatus according to the present invention is endless so as to move around and has a recording intermediate belt provided with an image forming area and a non-image forming area alternately on the outer peripheral surface thereof. Each of the image forming areas of the recording intermediate belt that moves around is arranged so as to be sequentially opposed to each other, and the image forming operation is performed based on the image signal while being pressed by the recording intermediate belt. A plurality of image forming units each provided with a head, and an image transfer unit that transfers an image formed by each image forming unit to recording paper, and a recording head of each image forming unit is provided on a recording intermediate belt. The image forming areas are arranged at intervals longer than the length of the image forming areas along the circling direction.

The image transfer section is provided with a transfer head for transferring an image on a recording intermediate belt to recording paper, and this transfer head is moved relative to a recording head of an image forming section close to the image transfer section. The image forming areas provided on the recording intermediate belt are arranged at an interval longer than the length of the image forming area along the circling direction.

Also, the image forming apparatus of the present invention is characterized in that the recording intermediate belt is wound around a drum driven to rotate, an auxiliary roller having a smaller diameter than the drum, and moves around. In the image forming area on the outer peripheral surface of
A plurality of image forming units provided so as to form images of different colors, and an image transfer unit for transferring an image formed by each image forming unit to recording paper, wherein the recording intermediate belt is fixed. And the orbital movement is performed at a constant torque by the auxiliary roller.

Further, the image forming apparatus of the present invention comprises a drum, a recording intermediate belt wound around a roller having a smaller diameter than the drum and moving around, and an image forming area on an outer peripheral surface of the recording intermediate belt moving around. A plurality of image forming units provided so as to form images of different colors, an image transfer unit for transferring images formed by the image forming units to recording paper, and a recording device wound around the rollers. A roller tilt mechanism for moving one end of the roller in a direction in which the deviation of the recording intermediate belt is corrected, when the intermediate belt is displaced in the axial direction with respect to the roller; It is characterized by having.

The directions in which the deviation of the recording intermediate belt is corrected are a direction approaching the drum and a direction opposite thereto.

Further, the image forming apparatus of the present invention comprises a drum, a recording intermediate belt wound around a roller having a smaller diameter than the drum and moving around, and an image forming area on an outer peripheral surface of the recording intermediate belt moving around. A plurality of image forming units provided so as to form images of different colors, and an image formed by transferring the images formed by the image forming units to a recording sheet pressed against the outer peripheral surface of the recording intermediate belt. A transfer unit; and a peeling roller arranged along the roller so as to contact the recording paper at a peeling position between the recording paper on which the image has been transferred by the image transfer unit and the recording intermediate belt. It is characterized by.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an example of an embodiment of the image forming apparatus of the present invention. In this image forming apparatus, the recording intermediate belt 1 that is endless so as to move around
5 is used. This recording intermediate belt 15 is, for example,
On the surface of the belt-shaped belt body composed of a polyimide film of about 25 to 50 μm, the thickness is 5 to 30 μm.
As shown in FIG. 3A, functional layers made of a certain amount of fluorine-based rubber or silicone-based rubber are laminated, and the respective end faces of the belt main body abut against each other. Then, the joint formed by abutting the end surfaces is connected to each other by a connecting member 15c provided over the outer peripheral surface of each end portion, thereby being endless. At one side edge of the recording intermediate belt 15, a seam mark 15b is provided at an appropriate distance from the seam of the recording intermediate belt 15.

As shown in FIG. 1, a large-diameter platen drum 12 having a diameter of about 200 mm around which a recording intermediate belt 15 is wound is provided at a substantially central portion in a housing 11 having a rectangular parallelepiped shape. The platen drum 12 is accurately rotated by a stepping motor at a predetermined speed in a direction indicated by an arrow A in FIG.

A rubber having a rubber hardness of about 60 to 70 is provided on the outer peripheral surface of the platen drum 12 as an elastic body, and a high frictional force acts on the recording intermediate belt 15 by the elastic body. 15 is moved around. The recording intermediate belt 15 is accurately circulated at a predetermined speed by the platen drum 12 rotated by a stepping motor.

On the side of the platen drum 12, there is disposed a sub-drum 13 having a diameter of about 50 mm around which the recording intermediate belt 15 is wound. Also, this sub-drum 13
An auxiliary drive roller 14 having a diameter smaller than that of the platen drum 12 is disposed below the platen drum 12, and a recording intermediate belt 15 is wound around the platen drum 12, the sub-drum 13, and the auxiliary drive roller 14. A tension roller 16 is pressed between the sub-drum 13 and the auxiliary drive roller 14 on the outer peripheral surface of the recording intermediate belt 15, and tension is applied to the recording intermediate belt 15 by the tension roller 16.

The auxiliary drive roller 15 is constituted by, for example, a torque limiter, and is rotated in the same direction as the platen drum 12 with a predetermined constant torque to move the recording intermediate belt 15 around with a constant torque.

The auxiliary drive roller 14 has one end movable by a roller inclining mechanism described later in a direction approaching the drum 12 and in an opposite direction. Is inclined at an appropriate angle with respect to the direction parallel to the axis of the.

Below the auxiliary drive roller 14, a peeling roller 18 having a smaller diameter than the auxiliary drive roller 14 is provided along the auxiliary drive roller 14. Peeling roller 18
Are urged to the auxiliary drive roller 14 by a constant spring force. The peeling roller 18 can rotate freely, and the recording intermediate belt 15 circulating around passes between the auxiliary driving roller 14 and the peeling roller 18.

In the outer peripheral area of the recording intermediate belt 15 facing the sub-drum 13, a dyeing layer transfer section 40 for transferring the dyeing layer to the outer peripheral surface of the recording intermediate belt 15 is arranged.

The dye transfer layer transfer section 40 is provided with a dye transfer member roll 43 formed by winding a dye transfer member in which a dye layer is laminated on a base material into a roll. When the dye transfer body pulled out from the dye transfer body roll 43 is opposed to the recording intermediate belt 15, the dye layer of the dye transfer body is moved around the recording intermediate belt 15 by the dye layer transfer head 44. Transferred to the surface. The dyeing layer is made of a resin having excellent dyeing properties. The base material of the dye transfer body onto which the dye layer has been transferred is wound up by the winding roll 42.

Above the platen drum 12, a first image forming unit 21 for forming a yellow image on a dyeing layer provided on the outer peripheral surface of the recording intermediate belt 15 by a dyeing layer transfer unit 40 is provided. And the first image forming section 2
1, a second image forming unit 22 that forms a magenta image on a dyeing layer provided on the outer peripheral surface of the recording intermediate belt 15 is provided adjacent to the rotation direction downstream side of the platen drum 12. I have. Further, adjacent to the second image forming unit 22 on the downstream side in the rotation direction of the platen drum 12,
A third image forming unit 23 for forming a cyan image on a dyeing layer provided on the outer peripheral surface of the recording intermediate belt 15 is provided.

The first to third image forming units 21 to 23
Each of the dye transfer bodies is wound in a roll shape, and has a dye transfer body cartridge 21a to 23a for drawing out and winding the wound dye transfer body, respectively. When the dye transfer member 23a faces the dyed layer of the recording intermediate belt 15, the dye transfer members are pressed against the dyed layer of the recording intermediate belt 15, respectively, to perform an image forming operation based on an image signal. The printing heads 21b to 23b that transfer the yellow, magenta, and cyan dyes are provided respectively.

The recording heads 21b to 23b sequentially transfer the yellow, magenta and cyan dyes onto the dyeing layer of the recording intermediate belt 15, respectively, so that a full-color image is formed on the dyeing layer. Is done.

Each of the recording heads 21b to 23b forms an image in a predetermined area on the outer peripheral surface of the recording intermediate belt 15. In the image forming area on the outer peripheral surface of the recording intermediate belt 15 where an image is formed, a non-image forming area where no image is formed is continuously provided.
Image forming areas and non-image forming areas are alternately formed on the outer peripheral surface of the recording intermediate belt 15.

As shown in FIG. 2, the dyeing layer transfer head 44 of the dyeing layer transfer section 40 and the recording head 21b of the first image forming section 21 move in a predetermined direction along the direction in which the recording intermediate belt 15 rotates. Are arranged at intervals slightly longer than the length of the image forming area which is equal to the image size of, for example, when the image forming area is A6 size,
The dyeing layer transfer head 44 and the recording head 21b of the first image forming unit 21 are spaced apart by 110 mm, which is longer than the image forming area.

The recording head 21b of the first image forming unit 21
Similarly, the recording head 22b of the second image forming unit 22 is also arranged at a longer interval than the image forming area along the direction in which the recording intermediate belt 15 rotates, and the second image forming Similarly, the recording head 22b of the unit 22 and the recording head 23b of the third image forming unit 23 are also arranged at intervals longer than the image forming area along the direction in which the recording intermediate belt 15 rotates.

Accordingly, when the recording head 23b of the third image forming unit 23 is in a state facing the non-image forming area,
The recording head 22b of the second image forming unit 22 faces a succeeding non-image forming region disposed with one image forming region therebetween, and the recording head 21b of the first image forming unit 21 Also, it is in a state of facing a subsequent non-image forming area arranged with one image forming area interposed therebetween. Further, the dyeing layer transfer head 44 of the dyeing layer transfer unit 40 also has
It is in a state of facing a subsequent non-image forming area disposed with one image forming area interposed therebetween.

Below the auxiliary drive roller 14, a recording paper roll 31 in which a recording paper 31a made of plain paper is wound into a roll is detachably provided. Recording paper 3
1a is pulled out from the lower portion of the recording paper roll 31 toward the platen drum 12 and abuts against the outer peripheral surface of the recording intermediate belt 15, and the platen drum 12 and the auxiliary drive roller 1
The recording roller 17 is pressed against the outer peripheral surface of the recording intermediate belt 15 by a transfer roller 17 disposed between the recording roller and the recording belt 4.

An image transfer section 50 is disposed inside the moving area of the recording intermediate belt 15 facing the transfer roller 17. The image transfer unit 50 includes a transfer head 51 that transfers the full-color image formed on the dyeing layer in the image forming area of the recording intermediate belt 15 together with the dyeing layer onto the recording paper 31a pressed against the recording intermediate belt 15. Is provided. The transfer head 51 is in a state of being in contact with the recording intermediate belt 15 and of being separated from the recording intermediate belt 15. Then, while the transfer head 51 is in contact with the recording intermediate belt 15, the full-color image formed on the recording intermediate belt 15 is transferred onto the recording paper 31a together with the dyed layer.

The transfer head 51 is connected to the third image forming unit 23
The recording head 23b is disposed at an interval longer than the image forming area provided on the recording intermediate belt 15 along the rotation direction of the recording intermediate belt 15,
Therefore, when the transfer head 51 faces the non-image forming area, the recording head 23 of the third image forming unit
b is in a state of facing a subsequent non-image forming area disposed with one image forming area interposed therebetween, and each recording head 22b of the second and first image forming sections 22 and 21
And 21b also face the following non-image forming areas arranged with one image forming area interposed therebetween. Further, the dyeing layer transfer head 4 of the dyeing layer transfer section 40
4 also faces a subsequent non-image forming area arranged with one image forming area interposed therebetween.

The recording intermediate belt 15 and the recording paper pass between the auxiliary driving roller 14 and the peeling roller 18, and the recording intermediate belt 15 that has passed between the auxiliary driving roller 14 and the peeling roller 18 The sheet is transported upward along the auxiliary drive roller 14. On the other hand, the recording paper 31a to which the full-color image has been transferred is conveyed so as to go straight, and the recording paper 31a is separated from the recording intermediate belt 15.

The recording paper 31a is
A cutter 32 for cutting the conveyed recording paper 31a is provided above the conveyance area of the recording paper 31a on the downstream side in the conveyance direction. The recording paper 31a on which the full-color image is transferred and travels straight passes through the lower region of the cutter 32, and when the region where the full-color image is formed extends from the housing 11, the cutter 32 is driven to record. The paper 31a is cut. The cut recording paper 31 a is stored in a paper discharge tray 33 provided outside the housing 11.

Between the sub-drum 13 and the platen drum 12, there is provided a seam sensor 26 for detecting a seam mark 15b provided on the side edge of the recording intermediate belt 15 which is rotated. FIG. 3A is a plan view of the joint sensor 26 and its peripheral portion, FIG. 3B is a side view thereof, and FIG. 3C is a front view thereof.

In the vicinity of the seam sensor 26, first and second belt sensors 2 for detecting that the seam mark 26 has shifted in the width direction of the recording intermediate belt 15 are provided.
7 a and 27 b are provided integrally with the seam sensor 26. Seam sensor 26, first and second
Each of the belt sensors 27a and 27b is constituted by, for example, a transmission type photo sensor.

The first belt sensor 27a and the second belt sensor 27b are arranged at predetermined intervals along the width direction of the recording intermediate belt 1, and when the seam sensor 26 detects the seam mark 15b. , Respectively. When the first and second belt sensors 27a and 27b detect the seam mark 15b, they are turned on.

Therefore, both belt sensors 27a and 27a
7b, when the seam mark 15b provided on the recording intermediate belt 15 is positioned, the both belt sensors 27a
And 27b are off. When the recording intermediate belt 15 meanders, the recording intermediate belt 1
5 is the first belt sensor 2 for such a state.
7A, the first belt sensor 27a detects the seam mark 15b and turns on, and the recording intermediate belt 15 shifts in the opposite direction by a predetermined distance. The sensor 27b detects the joint mark 15b and turns on.

FIG. 4 shows that one end of the auxiliary driving roller 14 disposed below the sub-drum 13 is moved in a direction approaching the drum 12 and in an opposite direction, and the auxiliary driving roller 14 is FIG. 4 shows a roller inclining mechanism for inclining with respect to a direction parallel to the direction of FIG.
(A) is a side view thereof, and (b) of FIG.
It is sectional drawing which followed the -A line.

Roller shaft 14 of auxiliary drive roller 14
A cam follower sheet metal 28a is connected to an end of the “a”. The cam follower sheet metal 28a is formed of a triangular flat plate, and one end of the roller shaft 14a is rotatably supported at a portion near one corner. A portion near the other corner of the cam follower sheet metal 28a is rotatably supported at an appropriate position on the housing 11 by a fulcrum pin 28b. Then, the cam follower sheet metal 28a rotates to one side around the fulcrum pin 28b, so that one end of the auxiliary drive roller 14
It is moved in a direction approaching the drum 12. When the cam follower sheet metal 28a rotates in the opposite direction, the auxiliary drive roller 1
One end of 4 is moved away from drum 12.

A cam follower 28e formed of a pin is provided in a portion near another corner of the cam follower sheet metal 28a.
Is a cam groove 2 provided in a disk-shaped drive cam 28c.
9f (see FIG. 4B) so as to be slidable.

The drive cam 28c is rotated forward and backward by a motor 28d.
8c, the cam followers 28e are respectively moved along the respective rotation directions, and the cam followers 28e are moved.
8a is rotated in both directions about the fulcrum pin 28b. The motor 28d, based on the detection results of the first and second belt sensors 27a and 27b described above,
It is driven forward and reverse.

The motor 28 is located near the driving cam 28c.
A first motor stop sensor 29a and a second motor stop sensor for detecting that the drive cam 28c has rotated forward and reverse over a predetermined center angle by the rotation of d, respectively, and stops the forward drive and reverse drive of the motor 28d, respectively. 29b are provided. The first and second motor stop sensors 29a and 29b are:
The driving cam 29c is provided in the rotation area of the disc-shaped driving cam 29c.
They are arranged apart from each other over 1/4 circumference in the circumferential direction of c. The first motor stop sensor 29a is turned on when the drive cam 28c is turned to one side by 3/4 rotation by the forward drive of the motor 28d,
As a result, the forward drive of the motor 28d is stopped.
The second sensor 29b is turned on when the drive cam 28c is rotated in the opposite direction by ／ rotation by the reverse rotation of the motor 28d, whereby the motor 2d is turned on.
The reverse drive of 8d is stopped.

In the image forming apparatus having such a configuration, a predetermined number of full-color images can be continuously formed. In this case, the recording intermediate belt 15 circulated by the platen drum 12 and the auxiliary drive roller 14
The outer peripheral surface of the dyeing layer transfer head 40 of the dyeing layer transfer section 40
4, the dyed layer is transferred continuously. Then, the recording intermediate belt 1 is rotated by the recording intermediate belt 15 so that
The first image forming area on the dyeing layer transferred to No. 5 is the first image forming area.
To the image forming unit 21.

The position of the first image forming area transferred to the recording intermediate belt 15 is detected based on the rotation of a stepping motor that drives the platen drum 12 to rotate, and is located in front of the first image forming area. When the located non-image forming area faces the recording head 21b of the first image forming unit 21, the recording head 21b is pressed against the non-image forming area. Then, the recording head 21b
Starts the image forming operation in synchronization with the circumferential movement of the recording intermediate belt 15.

In this case, the dye layer transfer head 44 of the dye layer transfer section 40 is in contact with the non-image forming area of the recording intermediate belt 15 following the first image forming area. Even if the change in load when the recording head 21b of the first image forming unit 21 contacts the recording intermediate belt 15 affects the transfer of the dyed layer by the dyed layer transfer head 44, the dyed layer portion No image is formed.

The recording head 21b of the first image forming unit 21 in which the image forming operation has been started in the non-image forming area moves on the dyed layer in the first image forming area as the recording intermediate belt 15 moves around. Then, a yellow image is formed based on a predetermined image signal. When the recording head 21b of the first image forming unit 21 forms the first image forming area yellow image, the recording intermediate belt 1 following the first image forming area.
5 is pressed against the non-image forming area. And
In such a state, the image forming operation of the recording head 21b is stopped.

At this time, the non-image forming area provided in front of the first image forming area where the yellow image is formed by the recording head 21b faces the recording head 22b of the second image forming section 22. Then, the recording head 22b of the second image forming unit 22 is pressed against the non-image forming area, and the image forming operation is started in synchronization with the conveyance of the recording intermediate belt 15.

In this case, the recording head 21b of the first image forming section 21 is pressed against the non-image forming area following the first image forming area where the yellow image is formed, and The image forming operation is started almost simultaneously with the image forming operation of the recording head 22b of the image forming unit 22. Therefore, the recording head 22b of the second image forming unit is pressed against the recording intermediate belt 15, and
2b, the first image forming unit 2
There is no possibility that the image forming operation by the first recording head 21b is affected, and the image forming operation by the recording head 21b of the first image forming unit 21 is started by the recording head 22b of the second image forming unit 22. There is no possibility that the operation is affected.

Further, the dyeing layer transfer head 44 of the dyeing layer transfer section 40 is also pressed against the non-image forming area of the recording intermediate belt 15 which is located behind the second image forming area. Recording head 22 of the second image forming unit
b is pressed by the recording intermediate belt 15 and the start of the image forming operation of each of the recording heads 22b and 21b affects the transfer of the dyed layer by the dyed layer transfer head 44, No image is formed on the dyed layer portion.

The recording head 22b of the second image forming unit 22 in which the image forming operation has been started in the non-image forming area moves on the dyeing layer in the first image forming area as the recording intermediate belt 15 moves around. In addition, a magenta image is formed based on a predetermined image signal, and the recording head 21b of the first image forming unit 21 in which the image forming operation is started in the non-image forming area
Also, as the recording intermediate belt 15 rotates, a yellow image is formed on the dyed layer in the second image forming area based on a predetermined image signal. Then, the recording intermediate belt 15
Of the second and first image forming units 22
The recording heads 22b and 21b of the recording intermediate belt 15 are pressed against the non-image forming areas following the first and second image forming areas of the recording intermediate belt 15, respectively, so that the image forming operations of the recording heads 22b and 21b are performed. Each will be stopped.

At this time, the non-image forming area in front of the first image forming area where the yellow and magenta images are formed is opposed to the recording head 23b of the third image forming unit 23, The recording head 23b of the third image forming unit 22 is pressed against the formation area, and the image forming operation is started in synchronization with the movement of the recording intermediate belt 15.

Also in this case, the recording heads 22b and 21b of the second and first image forming units 22 and 21 are
The image forming operation is pressed against the non-image forming areas following the first and second image forming areas, respectively, and substantially simultaneously with the image forming operation of the recording head 23b of the third image forming unit 23. Start. Therefore, the recording head 23b of the third image forming unit is driven by the recording intermediate belt 1
5 and the start of the image forming operation of the recording head 23b, the second and first image forming sections 22
The image forming operation by the recording heads 22b and 21b of the second and first image forming units 22 and 21 is not affected, and the third image is formed by the start of the image forming operation by the recording heads 22b and 21b of the second and first image forming units 22 and 21. There is no possibility that the image forming operation by the recording head 23b of the forming unit 23 is affected.

Further, even if the transfer of the dyed layer in the image forming area by the dyed layer transfer head 44 of the dyed layer transfer section 40 is affected, no image is formed on that portion.

The recording head 22b of the third image forming unit 22 in which the image forming operation is started in the non-image forming area is moved onto the dyeing layer in the first image forming area as the recording intermediate belt 15 moves around. Forming a cyan image based on a predetermined image signal, and similarly, the recording heads 22b and 21b of the second and first image forming units 22 and 21 in which the image forming operation is started in the non-image forming area. 21b also forms magenta and yellow images on the second and third image forming areas based on a predetermined image signal as the recording intermediate belt 15 rotates.

Then, the recording head 23b of the third image forming unit 23 is moved by the orbital movement of the recording intermediate belt 15,
While being pressed against the non-image forming area following the first image forming area of the recording intermediate belt 15, the recording heads 22b and 21b of the second and first image forming units 22 and 21 are pressed.
Is pressed against the non-image forming areas following the second and third image forming areas of the recording intermediate belt 15, respectively. In such a state, the recording heads 23b, 22b, 21
The image forming operation of b is stopped.

In this way, a full-color image is formed in the first image forming area, a yellow and magenta image is formed in the second image forming area, and a third image forming area is formed. To form a yellow image.

Thereafter, similarly, in the non-image forming area, the image forming operation of each of the recording heads 21b to 23b is started and stopped, whereby the recording intermediate belt 1 is started.
The image is formed in each image forming area by each of the recording heads 21b to 23b with the orbital movement of No. 5. As a result, a full-color image is continuously formed on each image forming area of the recording intermediate belt 15.

In the dyeing layer transfer section 40, when the transfer of the dyeing layer having a length corresponding to the predetermined number of image forming areas is completed, the dyeing layer transfer head 44 moves to the non-image forming area of the recording intermediate belt 15. In the contact state, the recording intermediate head 15 is separated. In this case, the recording heads 21b to 23b of the image forming units 21 to 23 are pressed against the non-image forming areas of the recording intermediate belt 15, respectively.
There is no fear that the image formation in each of the image forming units 21 to 23 is affected by the load fluctuation of the recording intermediate belt 15 when the dyeing layer transfer head 44 separates from the recording intermediate belt 15.

The recording heads 21b to 23b of the image forming sections 21 to 23 are pressed against the non-image forming areas after the dyeing layer of the recording intermediate belt 15 has passed, thereby forming the image. After the operation is completed, the recording belts are sequentially separated from the recording intermediate belt 15. Each image forming unit 21
When the recording heads 21b to 23b are separated from the recording intermediate belt 15, the other recording heads are pressed against the non-image forming areas, or have already been separated from the recording intermediate belt 15. In this state, a load change of the recording intermediate belt 15 when the recording heads 21b to 23b separate from the recording intermediate belt 15 may affect the image forming operation of the other recording heads 21b to 23b. Absent.

When a full-color image is not to be continuously formed on each image forming area of the recording intermediate belt 15 in this manner, the dyeing layer transfer head 44 of the dyeing layer transfer section 40 rotates the image forming apparatus. The dyed layer transferred to the moving recording intermediate belt 15 is cut into a predetermined size based on the image signal, and the first to third image forming units 21 to 23 record on the dyed layer. By the heads 21b to 23b,
An image of a predetermined color is formed.

In this case, the recording heads 21b to 23b of each image forming section are pressed by the recording intermediate belt 15 in the non-image forming areas where the dyed layer is not transferred, respectively, to start the image forming operation. When the recording heads 21b to 23b are pressed against the non-image forming area by passing through the image forming area, the image forming operation of the recording heads 21b to 23b is stopped.
The recording heads 21b to 23b are separated from the recording intermediate belt 15, respectively. Therefore, each of the image forming units 21 to 2
3, the image forming operation by the recording heads 21b to 23b
Recording intermediate belt 1 by other recording heads 21b to 23b
There is no possibility of being affected by the load fluctuation of 5, for example.

When a full-color image is formed in the image forming area of the dyed layer, the image forming area is sequentially conveyed to the image transfer unit 50 by the orbital movement of the recording intermediate belt 15, and
The transfer head 51 of the image transfer unit 50 is
5, the dyed layer on which the full-color image is formed is transferred to the recording paper 31 a conveyed integrally with the recording intermediate belt 15.

Also in this case, when the transfer head 51 is pressed by the recording intermediate belt 15 in the non-image forming area where the dyed layer has not been transferred, the transfer head 51 is formed in the image forming area when passing through the image forming area. The image is transferred to the recording paper 31a. Therefore, there is no possibility that the load fluctuation of the recording intermediate belt 15 when the transfer head 51 is pressed against the recording intermediate belt 15 affects the image forming operation of the recording heads 21b to 23b of the image forming units 21 to 23.

Recording paper 31a on which a full-color image has been transferred
Is transported integrally with the recording intermediate belt 15 and passes between the auxiliary driving roller 14 and the peeling roller 18, the recording intermediate belt 15 is transported upward, and the recording paper 31a is moved straight, The paper 31a is the recording intermediate belt 15.
Peeled off from In this case, the peeling roller 18 is in a state of being urged along the axial direction with respect to the auxiliary driving roller 14, and the recording paper 31 is moved by the peeling roller 18.
a is pressed against the auxiliary drive roller 14 linearly. As a result, the position where the recording paper 31a to which the full-color image has been transferred is separated from the recording intermediate belt 15 is clear,
The recording paper 31a is reliably separated from the recording intermediate belt 15. Thereby, the recording paper 31 from the recording intermediate belt 15 is
The peelability of a is improved.

Thereafter, the recording paper 31 a peeled off from the recording intermediate belt 15 goes straight, passes below the cutter 32, and passes through a discharge tray 33 provided outside the casing 11.
Is located above. When the recording paper 31a extends from the housing 11 over a length corresponding to the image forming area, the cutter 32 is driven to cut the recording paper 31a. The cut recording paper 31a is accommodated in a paper discharge tray 33 arranged below the recording paper 31a.

The driving of the cutter 32 causes the recording paper 31 a
Is cut to a predetermined length, the cutter 32 comes into contact with the recording paper 31a, causing a load fluctuation or the like. However, since the peeling roller 18 disposed opposite to the auxiliary drive roller 14 is pressed against the recording paper 31a, a change in load applied to the recording paper 31a by the peeling roller 18 causes the recording paper 31a to change. Transmission to the recording intermediate belt 15 is prevented.

As a result, there is no possibility that the load of the recording intermediate belt 15 fluctuates while the image is formed by the recording heads 21b to 23b in the image forming sections 21 to 23. There is no possibility that color unevenness or the like occurs in the images formed by the units 21 to 23.

During such an image forming operation, the recording intermediate belt 15 has the dimensional accuracy of the recording intermediate belt 15, the platen drum 12, the sub-drum 13, and the auxiliary driving roller 1.
4 There is a possibility that the recording intermediate belt 15 may meander depending on the dimensional accuracy of each of them, and furthermore, their assembly accuracy and the like. When the recording intermediate belt 15 meanders, the recording intermediate belt 15 is shifted with respect to the auxiliary driving roller 14 in the axial direction (the width direction of the recording intermediate belt 15).

When the meandering of the recording intermediate belt 15 advances, the recording intermediate belt 15 is largely shifted with respect to the recording heads 21b to 23b in each of the image forming units 21 to 23, and an image is recorded on the recording intermediate belt 15. There is a possibility that it cannot be formed accurately. For this reason, meandering of the recording intermediate belt 15 is suppressed by the roller inclination mechanism.

In this case, when the seam mark 15b of the recording intermediate belt 15 that is circulated is detected by the seam sensor 26, the first and second belt sensors 27a and 27 that are arranged close to the seam sensor 26.
b is operated. Then, for example, as shown in FIG. 5A, the seam mark 1 provided on the recording intermediate belt 15
When the first belt sensor 27a detects the seam mark 15b and turns on because the first belt sensor 27a is shifted by a predetermined distance toward the first belt sensor 27a, the first belt sensor 27a is provided in the roller tilt mechanism. The motor 28d is driven to rotate forward, and the driving cam 28c is rotated in a predetermined direction. As a result, the cam follower sheet metal 28c is rotated about the fulcrum pin 28b.

Thereafter, the cam follower sheet metal 28c is 3/4
When the rotation around the circumference is detected by the first motor stop sensor 29a, the normal rotation drive of the motor 28d is stopped. Thereby, as shown in FIG. 5B, the end of the roller shaft 14a of the auxiliary drive roller 14 supported by the cam follower sheet metal 28c is moved in a direction away from the drum 12, and the auxiliary drive roller 14 12 are inclined with respect to a direction parallel to the axis of the twelve axes.

When the recording intermediate belt 15 is rotated in such a state, the recording intermediate belt 15 wound around the auxiliary drive roller 14 is moved from the first belt sensor 27a to the second belt sensor 27a by the circular movement. Sequentially slide toward the belt sensor 27b. Then, as shown in FIG. 5C, when the recording intermediate belt 15 slides over a predetermined distance and the second belt sensor 27b is operated, the seam mark 15b is detected and turned on. The motor 28d provided in the tilt mechanism is driven to rotate in the reverse direction, the drive cam 28c is rotated in a predetermined direction, and the cam follower sheet metal 28c is rotated about the fulcrum pin 28b. Then, when the second motor stop sensor 29b detects that the cam follower sheet metal 28c has been rotated over 3/4 rotation, the reverse rotation drive of the motor 28d is stopped.

As a result, as shown in FIG. 5D, the auxiliary drive roller 14 supported by the cam follower sheet metal 28c
Of the roller shaft 14a is moved in a direction approaching the drum 12, and the auxiliary drive roller 14 is inclined in the opposite direction.

When the recording intermediate belt 15 is circulated in such a state, the recording intermediate belt 15 wound around the auxiliary drive roller 14 is moved from the second belt sensor 27b to the first belt sensor with the circulating movement. It slides sequentially toward 27a. Then, when the recording intermediate belt 15 slides over a predetermined distance, FIG.
As shown in (1), the first belt sensor 27a detects the seam mark 15b and turns on.

Thereafter, the same operation is repeated so that the recording intermediate belt 15 is controlled such that one side edge is located between the first belt sensor 27a and the second belt sensor 27b. The meandering is suppressed, and there is no possibility that the recording heads 21b to 23b of the image forming apparatuses 21 to 23 are greatly displaced. An image is appropriately formed by the recording heads 21b to 23b.

The recording intermediate belt 15, on which an image is formed on the dyed layer, is circulated at a constant speed by a rotationally driven platen drum 12, and a constant torque is generated by an auxiliary driving roller. It has been orbiting given. Therefore, the recording intermediate belt 15 that is rotated around is always moved with a constant torque between the platen drum 12 and the auxiliary drive roller 14, and there is no possibility that the tension is reduced. As described above, the recording intermediate belt 1 circulated by the rotation of the platen drum 12
In No. 5, there is no possibility that the tension is lowered on the downstream side in the rotation direction of the platen drum 12, and therefore, the initial tension of the recording intermediate belt 15 can be suppressed to be small. As a result, the running load of the recording intermediate belt 15 can be reduced, and the life of the recording intermediate belt 15 can be extended.

[0085]

As described above, in the image forming apparatus of the present invention, the recording heads of the respective image forming sections are respectively pressed in the non-image forming areas of the recording intermediate belt to start the image forming operation. Since the image forming operation is stopped and separated in the image forming area, a load change caused by another recording head being pressed against the recording intermediate belt while the recording head is forming an image. There is no risk of being affected by load fluctuations at the start and stop of the image forming operation of the recording head, so that each image formed by each image forming section does not have color unevenness or the like, and is sharp. A full-color image can be formed.

Further, the recording intermediate belt is circulated at a constant speed by the drums arranged to face the respective image forming units, and is circulated by the auxiliary driving roller at a constant torque. In addition, the tension applied to the recording intermediate belt can be reduced, and the recording intermediate belt can be stably used for a long period of time.

Further, the roller around which the recording intermediate belt is wound is inclined with respect to a direction orthogonal to the direction in which the recording intermediate belt circulates so that one side edge of the recording intermediate belt is within a predetermined range. Therefore, meandering of the recording intermediate belt can be suppressed.

Further, since the peeling roller is pressed linearly at the peeling position of the recording paper peeled from the recording intermediate belt, the peeling position of the recording paper relative to the recording intermediate belt becomes clear, and The releasability of the recording paper is improved. In addition, since the peeling roller is in pressure contact with the recording paper, there is no fear that the load fluctuation of the recording paper generated when the recording paper is cut by the cutter is transmitted to the recording intermediate belt.

[Brief description of the drawings]

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

FIG. 2 is a schematic diagram illustrating a relationship between a recording intermediate belt and a recording head of each image forming unit.

3A is a plan view illustrating a schematic configuration of a seam sensor and a belt sensor provided in the image forming apparatus, FIG. 3B is a side view thereof, and FIG. 3C is a front view thereof.

FIG. 4A is a side view illustrating a roller tilting mechanism that tilts an auxiliary driving roller provided in the image forming apparatus;
(B) is a sectional view taken along line AA of (a).

FIGS. 5A to 5D are schematic diagrams each showing a relationship between an auxiliary driving roller and a recording intermediate belt.

[Explanation of symbols]

 11 Housing 12 Platen Drum 13 Sub Drum 14 Auxiliary Driving Roller 15 Recording Intermediate Belt 15b Joint Mark 15c Connecting Member 16 Tension Roller 17 Transfer Roller 18 Peeling Roller 21-23 Image Forming Units 21b-23b Recording Head 27a First Belt Sensor 27b Second Belt sensor 28a cam follower sheet metal 28b fulcrum pin 28c drive cam 28d motor 29a first motor stop sensor 29b second motor stop sensor 31 recording paper roller 31a recording paper 40 dyeing layer transfer unit 44 first arrival layer transfer head 50 image transfer unit 51 Transfer Head

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Haruo Yamashita 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Tetsuya Morita 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.F-term (reference) 2C065 AA01 AB09 AC03 CJ01 CJ02 CJ08 DA32 DC04 DC10 DC29 DC32

Claims (6)

[Claims] Claims: 1. An endless device for orbiting,
A recording intermediate belt in which an image forming area and a non-image forming area are alternately provided on the outer peripheral surface thereof, and the image forming areas of the recording intermediate belt moving around are arranged so as to sequentially face each other. A plurality of image forming units each provided with a recording head for performing an image forming operation based on an image signal while being pressed against the recording intermediate belt; and transferring an image formed by each image forming unit to recording paper. And an image transfer unit, wherein the recording heads of each image forming unit are arranged at intervals longer than the length of the image forming area provided on the recording intermediate belt along the circumferential movement direction. Image forming apparatus. 2. The image transfer section is provided with a transfer head for transferring an image on a recording intermediate belt to recording paper,
The transfer head is disposed at an interval longer than the length of the image forming area provided on the recording intermediate belt along the circumferential movement direction with respect to the recording head of the image forming unit adjacent to the image transfer unit. The image forming apparatus according to claim 1. 3. A recording intermediate belt that is wound around a rotationally driven drum, an auxiliary roller smaller in diameter than the drum, and moves around, and an image forming area on an outer peripheral surface of the recording intermediate belt that moves around. A plurality of image forming units provided so as to form images of different colors, and an image transfer unit for transferring the image formed by each image forming unit to a recording sheet, wherein the recording intermediate belt, An image forming apparatus, wherein the image forming apparatus is moved around at a constant speed and is moved around at a constant torque by the auxiliary roller. 4. A drum, a recording intermediate belt wound around a roller having a smaller diameter than the drum and moving around, and an image forming area on the outer peripheral surface of the recording intermediate belt moving around, and images of different colors are formed on the drum. A plurality of image forming units provided so as to form, an image transfer unit that transfers an image formed by each image forming unit to recording paper, and a recording intermediate belt wound around the roller, And a roller tilt mechanism for moving one end of the roller in a direction in which the deviation of the recording intermediate belt is corrected when the roller is shifted in the axial direction. Image forming device. 5. The image forming apparatus according to claim 4, wherein directions in which the deviation of the recording intermediate belt is corrected are a direction approaching the drum and a direction opposite thereto. 6. A drum, a recording intermediate belt wound around a roller having a smaller diameter than the drum and moving around, and an image forming area on an outer peripheral surface of the recording intermediate belt moving around, and images of different colors are respectively formed on the drum. A plurality of image forming units provided so as to form, an image transfer unit for transferring an image formed by each image forming unit to recording paper pressed against the outer peripheral surface of the recording intermediate belt, and the image transfer unit An image forming apparatus comprising: a separation roller disposed along the roller so as to contact the recording sheet at a separation position between the recording sheet onto which the image has been transferred and the recording intermediate belt.