JP2006160504A - Carrying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carrying device capable of preventing it from being deformed due to the concentration of loads onto a part of an endless belt. <P>SOLUTION: In printing, a stepping motor 90 is rotated by a prescribed angle to bring the tip part of a cam 82 into contact with the surface of a pedestal 78 so as to push down the pedestal 78. The pedestal 78 is rotated downward about a fixed shaft 80 to extend a pressuring spring 76 so as to move a moving shaft 74 downward. By the movement, the pressuring roller 66 is pressed against the inner peripheral surface of the endless belt 52 with a prescribed pressure, and a proper tension is applied to the endless belt 52 by the pressuring roller 66. In a printing wait state, since the cam is rotated by approximately 90° from the state of printing and the cam 82 is separated from the pedestal 78, the pressuring roller 66 is merely brought into light contact with the endless belt 52 and the pressuring roller 66 does not press down the endless belt 52. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transport device that transports a recording medium placed on an endless belt that rotates in a predetermined rotation direction.

  2. Description of the Related Art Inkjet image forming apparatuses (inkjet recording apparatuses) that form images by ejecting ink onto recording media such as recording paper are widely used. 2. Description of the Related Art An ink jet image forming apparatus performs recording (image formation) by ejecting ink from a printing unit (printing head) onto a recording medium. Two types of print heads are known, which are fixed during recording (during printing) and do not move, and two types in which the print head is mounted on a carriage that scans in a predetermined main scanning direction.

  In the type in which the print head is fixed, a belt conveying device that easily conveys the recording medium at a constant speed is often used as the recording medium conveying device. As a belt conveyance device, a configuration is known in which an endless belt is stretched between a driving roller and a driven roller separated by a predetermined distance, and the endless belt is rotated by rotating the driving roller with a motor or the like. When a recording medium is placed on a rotating endless belt and transported, it is a necessary condition for improving the image quality to transport the recording medium at a constant speed. For this reason, a mechanism for applying a constant tension to the endless belt may be provided so that the recording medium can be stably conveyed by preventing the endless belt from varying in length or slipping due to the elongation of the endless belt. It is common.

  In the mechanism that applies a constant tension to the endless belt, a load (tension) is applied uniformly to the entire circumference of the endless belt while the endless belt is rotating. However, when the endless belt is stopped, the portion of the endless belt that is wound around the driving roller and the driven roller continues to be loaded while being bent (the state of being bent continues). Become. When such a state lasts for a long time, the endless belt made of rubber or the like may be bent and the bent portion may be deformed.

  Further, in the endless belt with a wrinkle, a convex portion due to wrinkles is formed on the flat portion of the endless belt, and the recording medium is not transported flat on the endless belt. If the recording medium is not transported flat on the endless belt, not only accurate image formation is not performed on the recording medium, but also the recording medium may come into contact with the print head and cause jamming. .

  In view of the above circumstances, an object of the present invention is to provide a conveyance device that prevents deformation caused by load concentration on a part of an endless belt.

In order to achieve the above object, a transport apparatus according to the present invention is a transport apparatus that mounts and transports a recording medium on an endless belt that rotates in a predetermined rotation direction.
(1) A tension adjusting mechanism for adjusting a tension for tensioning the endless belt is provided.

here,
(2) The tension adjusting mechanism applies a predetermined tension to the endless belt while the endless belt is rotating, and reduces the tension acting on the endless belt to be less than the predetermined tension while the endless belt is stopped. You may do.

Also,
(3) The tension adjusting mechanism may continuously adjust the tension.

further,
(4) The tension adjusting mechanism may adjust the tension stepwise.

Furthermore,
(5) a driving roller that is rotated by a driving force transmitted from a predetermined driving source, and a driven roller that is disposed away from the driving roller;
(6) The endless belt may be stretched between the driving roller and the driven roller.

Furthermore,
(7) The endless belt is composed of a plurality of endless belts arranged in a direction orthogonal to the rotation direction,
(8) The tension adjusting mechanism may individually adjust tensions of the plurality of endless belts.

Furthermore,
(9) The tension adjusting mechanism is
(9-1) a pressure roller that pressurizes the inner peripheral surface of the endless belt toward the outside;
(9-2) A pressing unit that presses the pressure roller against the inner circumferential surface of the endless belt at a predetermined timing to pressurize the inner circumferential surface may be provided.

Furthermore,
(10) The pressing means includes
(10-1) levers for supporting both ends in the longitudinal direction of the pressure roller;
(10-2) a pedestal extending away from the lever and extending in the longitudinal direction of the lever;
(10-3) a biasing means for biasing the lever so that the longitudinal end of the lever and the longitudinal end of the pedestal approach each other;
(10-4) It may include a cam that presses the pedestal at a predetermined timing so that one end in the longitudinal direction of the pedestal is separated from one end in the longitudinal direction of the lever.

Furthermore,
(11) The endless belt may be formed with a plurality of openings for adsorbing the recording medium to the endless belt.

Furthermore,
(12) The endless belt may include a restricting member that restricts the endless belt from moving in a direction orthogonal to the rotation direction.

  According to the present invention, when a recording medium is conveyed by rotating the endless belt, a predetermined tension is applied to the endless belt by the tension adjusting mechanism, while when the recording medium is not conveyed by stopping the endless belt, the endless belt is applied. Loosen the tension acting on the. When tension is applied to the endless belt even when the endless belt is stopped (not rotating), a part of the endless belt remains in strong contact with the driving roller and the driven roller. There is a possibility that the load is concentrated on the part and the endless belt is deformed. However, when the endless belt is stopped, the load is not concentrated on a part of the endless belt while the endless belt is stopped by reducing the tension to zero by the tension adjusting mechanism. For this reason, the deformation | transformation resulting from a load concentrating on a part of endless belt can be prevented. Further, since the time for applying the tension to the endless belt is shortened, the elongation of the endless belt can be suppressed to the minimum, and the life of the endless belt can be extended.

  The present invention has been realized in an ink jet printer that forms an image by ejecting ink onto a recording medium such as recording paper.

  With reference to FIG. 1, an example of a printer in which the conveyance device of the present invention is incorporated will be described.

  FIG. 1 is a front view schematically showing an example of a printer in which the conveyance device of the present invention is incorporated.

  A recording unit 20 that discharges ink to form an image on the recording medium P is disposed at the top of the printer 10, and below this recording unit 20 is a recording medium in the direction of arrow A (or the opposite direction). A transport device 50 for transporting P is disposed. The recording unit 20 is disposed on the base plate 24, and moves in the direction of approaching the transport device 50 or the direction of moving away from the transport device 50 together with the base plate 24 as necessary.

  In the recording unit 20, print heads (recording heads) 22K, 22C, 22M, and 22Y (see FIG. 2) that discharge ink are in the direction of arrow A (the moving direction of an endless belt 52 described later, the transport direction of the recording medium). It is mounted side by side. The print heads 22K, 22C, 22M, and 22Y eject black, cyan, magenta, and yellow ink from the upstream side in the recording medium conveyance direction, respectively. Each of the print heads 22K, 22C, 22M, and 22Y is provided with nozzles arranged in a line in a direction orthogonal to the recording medium conveyance direction (width direction of the recording medium), and the four print heads 22K, 22C, An image is formed by overlapping the ink ejected from 22M and 22Y. Each of the print heads 22K, 22C, 22M, and 22Y is in a standby state in a state where the discharge port (nozzle opening) is blocked by a cap (not shown) in the recording unit 20, and the recording medium is transferred to the transport device 50. After being set and immediately before printing, it moves to a predetermined printing position and starts printing.

  An ink supply unit 26 that supplies ink to the print heads 22K, 22C, 22M, and 22Y is disposed on the back side of the printer 10. Inside the ink supply unit 26, an ink tank (not shown) for each color, an ink pump (not shown) for transporting ink to the recording unit 20, and water heads for the print heads 22K, 22C, 22M, 22Y A sub tank (not shown) for providing a predetermined negative pressure due to the difference is arranged.

  When the recording medium passes below the recording unit 20, black, cyan, magenta, and yellow inks are sequentially ejected onto the recording medium to form a color image. Each of the print heads 22K, 22C, 22M, and 22Y is appropriately supplied with ink from the ink tank via the ink flow path 26a by a supply pump (not shown).

  The conveying device 50 includes an endless belt (conveying belt) 52 on which a recording medium is placed, a driving roller 54 and a driven roller 56 around which the endless belt 52 is stretched. In the printer 10, four endless belts 52 are arranged in parallel in a direction orthogonal to the rotation direction of the endless belt 52, but may be three or less or five or more. The driving roller 54 is located upstream in the recording medium conveyance direction (arrow A direction), and the driven roller 56 is located downstream in the recording medium conveyance direction.

  Both ends in the longitudinal direction of the rotation shaft of the drive roller 54 are supported by a frame (not shown) so as to be rotatable via bearings (not shown). A pulley 55 is attached to one end in the longitudinal direction of the rotation shaft of the drive roller 54, and a timing belt 60 is stretched between the pulley 55 and a drive motor (conveyance motor) 58. When the drive motor 58 is driven, the timing belt 60 and the pulley 55 are rotated, and the drive roller 54 is rotated. With this rotation, the four endless belts 52 rotate in the directions of arrows A and B. Note that both ends in the longitudinal direction of the rotating shaft of the driven roller 56 are supported by a frame (not shown) through a bearing (not shown) in the same manner as the drive roller 54. An encoder 64 that detects the number of rotations of the driven roller 56 is fixed to one end portion in the longitudinal direction of the rotation shaft of the driven roller 56.

  A pressure roller (tension roller) 66 that applies tension to the endless belt 52 is disposed between the driving roller 54 and the driven roller 56. The pressure roller 66 extends in parallel to the drive roller 54, and presses the inner peripheral surfaces of the four endless belts 52 outward to apply a predetermined tension to the endless belts 52 to tension them. ing. When the pressure roller 66 applies a predetermined tension to the endless belt 52, the endless belt 52 always maintains an ideal state, and the driving roller 54 rotates in this state so that the endless belt 52 rotates in the directions of arrows A and B. To do. A chamber 68 for adsorbing (sucking) the recording medium being conveyed by the endless belt 52 to the endless belt 52 is disposed below the endless belt 52. A fan unit 69 is disposed below the chamber 68, and the chamber 68 and the fan unit 69 are connected (connected) by a hose 69a. The endless belt 52 has a plurality of openings 52 a for adsorbing the recording medium to the endless belt 52. When the fan unit 69 is driven, air is sucked from the plurality of openings 52 a via the hose 69 a and the chamber 68, so that the recording medium is adsorbed to the endless belt 52.

  The electrical system of the printer 10 will be described with reference to FIG.

  FIG. 2 is a block diagram showing an electrical system of the printer of FIG.

  Recording data and commands transmitted from the host PC 12 are received by the CPU 100 via the interface controller 102. The CPU 100 is an arithmetic processing unit that performs overall control such as recording data reception, recording operation, and recording medium handling of the printer 10. After analyzing the received command, the CPU 100 renders the image data of each color component of the recording data by developing a bitmap on the image memory 106. As an operation process before recording, the capping motor 122 and the head up / down motor 118 are driven via the output port 114 and the motor driving unit 116, and the print heads 22K, 22C, 22M, and 22Y are capped (not shown). To move to a recording position (image forming position).

  Subsequently, a roll motor (not shown) that feeds the recording medium through the output port 114 and the motor driving unit 116, a conveyance motor 120 that conveys the recording medium at a constant speed, and the like are driven to convey the recording medium to the recording position. To do. The leading edge detection sensor (not shown) for determining the timing (recording timing) at which ink starts to be ejected onto the recording medium conveyed at a constant speed detects the leading edge position of the recording medium. Thereafter, in synchronism with the conveyance of the recording medium, the CPU 100 sequentially reads the recording data of the corresponding color from the image memory 106, and the read data is sent to each print head via the print head control circuit 112. Transfer to 22K, 22C, 22M, 22Y.

  The operation of the CPU 100 is executed based on a processing program stored in the program ROM 104. The program ROM 104 stores processing programs and tables corresponding to the control flow. A work RAM 108 is used as a working memory. During the cleaning and recovery operations of the print heads 22K, 22C, 22M, and 22Y, the CPU 100 drives the pump motor 124 via the output port 114 and the motor driving unit 116, and controls ink pressurization and suction.

  With reference to FIGS. 3 and 4, the conveying device 50 incorporated in the printer 10 will be described.

  FIG. 3 is a perspective view showing the conveying device during image formation (printing). FIG. 4 is a perspective view showing the transfer device during standby. These drawings are views seen from the opposite direction to FIG. In these drawings, the same components as those shown in FIG. 1 are denoted by the same reference numerals.

  The pressure roller 66 is located inside the endless belt 52 and is sandwiched between a pair of plate-like levers 70 extending in the recording medium conveyance direction. A long hole 70a is formed at the center in the longitudinal direction of the lever 70, and both ends in the longitudinal direction of the rotating shaft of the pressure roller 66 are movably inserted into these long holes 70a.

  One end of the pair of levers 70 in the longitudinal direction (end on the downstream side in the arrow A direction) is fixed to the fixed shaft 72 so as to be freely rotatable. Both ends in the longitudinal direction of the fixed shaft 72 are fixed to side plates (not shown), and the fixed shaft 72 does not move. The other end in the longitudinal direction of the pair of levers 70 (the end on the upstream side in the arrow A direction) is fixed to the moving shaft 74, respectively. One end portion of a pressurizing spring (tension spring) 76 (which is an example of a biasing means according to the present invention) is hung from a slightly central portion at both ends in the longitudinal direction of the moving shaft 74. The other end of the pressure spring 76 is hung on the other end in the longitudinal direction (end on the upstream side in the arrow A direction) of the pair of pedestals 78 extending in the recording medium conveyance direction. The pressure spring 76 urges both the other end in the longitudinal direction of the pedestal 78 and the moving shaft 74 to approach each other.

  One end of the pair of pedestals 78 in the longitudinal direction (end on the downstream side in the direction of arrow A) is rotatably fixed to a fixed shaft 80 extending in parallel with the pressure roller 66. Both ends in the longitudinal direction of the fixed shaft 80 are fixed to side plates (not shown). For this reason, the fixed shaft 80 does not move.

  On the upper surface side of the pedestal 78, an egg-shaped cam 82 that rotates the pedestal 78 about the fixed shaft 80 is disposed. As shown in FIG. 3, when the tip (thinned portion) of the cam 82 pushes down on the upper surface (surface) of the pedestal 78, the pedestal 78 rotates downward with the fixed shaft 80 as the central axis. Along with the movement, the pressure spring 76 is extended and the moving shaft 74 is lowered to press the pressure roller 66 against the inner peripheral surface of the endless belt 52. That is, when the distal end portion (thinned portion) of the cam 82 pushes down on the upper surface (front surface) of the pedestal 78, the other longitudinal end portion of the pedestal 78 and the other longitudinal end portion of the lever 70 are separated, thereby applying pressure. The urging force of the spring 76 acts on the lever 70, and the other longitudinal end of the lever 70 slightly pivots downward about the fixed shaft 72. The long hole 70a is moved to the upstream side in the recording medium conveyance direction, and the pressure roller 66 is pressed against the inner peripheral surface of the endless belt 52.

  The cam 82 is fixed to a cam shaft 84 that extends in parallel with the longitudinal direction of the pressure roller 66. Both ends of the cam shaft 84 in the longitudinal direction are fixed to side plates (not shown) via bearings (not shown). As the cam shaft 84 rotates, the cam 82 also rotates. A gear 86 is inserted into and fixed to one longitudinal end portion of the cam shaft 84. The gear 86 meshes with the motor gear 88, and the motor gear 88 is rotated by driving the stepping motor 90. When the stepping motor 90 is driven and the motor gear 88 is rotated by a predetermined angle, the cam shaft 84 is also rotated by a predetermined angle together with the gear 86, and the cam 82 is also rotated by this rotation.

  At the time of printing (image formation), the stepping motor 90 rotates by a predetermined angle in response to a command from the CPU 100 (see FIG. 2), so that the tip of the cam 82 is placed on the surface of the pedestal 78 as shown in FIG. The pedestal 78 is pushed down by contact, and thereby the pedestal 78 rotates downward about the fixed shaft 80, and by this rotation, the pressure spring 76 is extended and the moving shaft 74 moves downward. By this movement, the lever 70 rotates downward about the fixed shaft 72, and the pressure roller 66 is pressed against the inner peripheral surface of the endless belt 52 with a predetermined pressure. As a result, an appropriate tension (tension) is applied to the endless belt 52 by the pressure roller 66, so that the endless belt 52 does not slip on the driving roller 54 or move in a direction perpendicular to the conveying direction. Transport is realized. Note that the member such as the pressure roller 66 that restricts the endless belt 52 from moving in the direction orthogonal to the conveyance direction as described above is an example of the restriction member in the present invention.

  In the printing standby state, the stepping motor 90 is rotated by a command from the CPU 100 (see FIG. 2) so that the cam 82 rotates about 90 ° from the above-described printing state. As a result, as shown in FIG. 4, since the cam 82 is separated from the pedestal 78, the pressure roller 66 only lightly contacts the endless belt 52, and the pressure roller 66 does not push the endless belt 52 (almost). For this reason, since no extra load (tension) is applied to the endless belt 52, the endless belt 52 will not be wrinkled or deformed even if it is left for a long time. When the printing standby state is shifted to the printing state, the stepping motor 90 is driven and the cam 82 rotates to apply an appropriate tension to the endless belt 52, so that the state returns to the optimum state for conveyance.

  With reference to FIG. 5 and FIG. 6, the conveyance apparatus 150 of Example 2 is demonstrated.

  FIG. 5A is a perspective view showing the conveying device during image formation (printing), and FIG. 5B is an enlarged side view showing the cam. FIG. 6 is a perspective view showing the transfer device during standby. In these drawings, the same components as those shown in FIGS. 3 and 4 are denoted by the same reference numerals.

  The difference between the conveyance device 150 of the second embodiment and the conveyance device 50 of the first embodiment is the shape of the cam 152. The cam 82 (see FIG. 3 and the like) in the conveying device 50 of the first embodiment has an oval shape, a mode in which tension is applied to the endless belt 52 (state shown in FIG. 3), and tension (mostly) to the endless belt 52. It has a shape that allows the user to select two stages, ie, a mode that does not act (state shown in FIG. 4). That is, the tension applied to the endless belt 52 is adjusted stepwise.

  On the other hand, the cam 152 in the transport device 150 of the second embodiment is an eccentric cam, and has a shape in which the tension applied to the endless belt 52 can be continuously adjusted (changed). The cam 152 has a distal end surface 152a farthest (distant) from the cam shaft 84, a curved surface 152b that approaches the cam shaft 84 while smoothly curving from the distal end surface 152a, and a flat surface 152c extending to one end of the curved surface 152b. The shaft portion is provided with a torque limiter 152d managed at a predetermined torque.

  When the tip surface 152a of the cam 152 contacts the surface of the pedestal 78 and pushes down the pedestal 78, the pressure roller 66 pushes down the inner peripheral surface of the endless belt 52 most strongly, as shown in FIG. Maximum tension acts on 52. This tension is regulated by the torque limiter 152d. From this state, the stepping motor 90 is driven to slightly rotate the cam 152 in the direction of arrow E in FIG. 5B, so that the portion of the curved surface 152b of the cam 152 close to the tip surface 152a is the pedestal 78. The pedestal 78 is pushed down in contact with the surface of. In this state, the amount by which the pedestal 78 is pushed down (the amount by which the pedestal 78 is pushed down) is smaller than when the front end surface 152 a is in contact with the surface of the pedestal 78. That is, when the state is changed from the state in which the front end surface 152a is in contact with the surface of the pedestal 78 to the state in which the curved surface 152b is in contact with the surface of the pedestal 78, the pedestal 78 is slightly raised, and the pressure roller 66 Since it rises slightly, the force to push down the inner peripheral surface of the endless belt 52 is slightly weakened, and the tension acting on the endless belt 52 is also slightly weakened.

  From the above state, by further driving the stepping motor 90 and slightly rotating the cam 152 in the direction of arrow E, the amount by which the pedestal 78 is pushed down continuously decreases, and the force that pushes down the inner peripheral surface of the endless belt 52 is also increased. The tension is continuously weakened, and the tension acting on the endless belt 52 is also continuously weakened. In a state where the flat surface 152 c is in contact with the surface of the pedestal 78, the amount by which the pedestal 78 is pushed down is small, and almost no tension is applied to the endless belt 52.

  By using the cam 152 as described above, the tension applied to the endless belt 52 can be continuously adjusted, and a fine tension can be applied to the endless belt 52.

  6 is in the state shown in FIG. 6 during normal printing standby. When the image forming apparatus receives image data, the shaft 80 and the cam 152 are rotated by a driving source (not shown) to apply a predetermined tension to the endless belt 52. After a predetermined tension is applied and an ideal state for carrying the belt is obtained, the belt conveyance is started by the drive roller, and the image formation is started by the recording head in a state where the belt conveyance speed is controlled.

  With reference to FIG. 7, the conveyance apparatus 250 of Example 3 is demonstrated.

  FIG. 7 is a perspective view showing the conveying device during image formation (printing). In these drawings, the same components as those shown in FIGS. 3 and 4 are denoted by the same reference numerals.

  The conveyance device 250 according to the third embodiment is characterized in that tensions acting on the four endless belts 52 can be adjusted individually (independently). In the first embodiment and the second embodiment, the four endless belts 52 are integrated using a single pressure roller 66, and tension is applied thereto. On the other hand, in the conveyance device 250 of the third embodiment, for each endless belt 52, the pressure roller 252 (about one-fourth the length of the pressure roller 66), the pair of levers 70, and the fixed A shaft 72, a moving shaft 74, a pressure spring 76, a pedestal 78, a moving shaft 74, a fixed shaft 80, a cam 152, and the like are arranged. Although the cam shaft 154 is common to the four cams 152, each endless belt 52 even when the endless belts 52 vary due to the action of the torque limiter 152 d provided on each cam 152. Since an appropriate tension can be applied to each belt 52, the recording medium can be conveyed in a more stable state. As the endless belts 52 become longer, there is a high possibility that variations such as the elongation of the endless belts 52 will increase. Therefore, the advantage of adjusting the tension for each endless belt 52 increases.

  Further, the four cams 152 rotate about different independent cam shafts 154, and stepping motors (not shown) for rotating the four independent cam shafts 154 are also arranged independently. Thus, the tension acting on the four endless belts 52 may be adjusted individually (independently).

  As in the second embodiment, the belt tension is relaxed during standby for normal printing, and when the image forming apparatus receives image data, the shaft 154 and the cam 152 are rotated by the drive source (not shown) to the endless belt 52. A predetermined tension is applied. After a predetermined tension is applied and an ideal state for carrying the belt is obtained, the belt conveyance is started by the driving roller 54, and the image formation is started by the recording head while the belt conveyance speed is controlled.

FIG. 2 is a front view schematically illustrating an example of a printer in which the conveyance device of the present invention is incorporated. FIG. 2 is a block diagram illustrating an electrical system of the printer of FIG. 1. FIG. 6 is a perspective view illustrating a conveying device during image formation (during printing). It is a perspective view which shows the conveying apparatus in standby. (A) is a perspective view showing a conveying device during image formation (during printing), and (b) is an enlarged side view showing a cam. It is a perspective view which shows the conveying apparatus in standby. FIG. 6 is a perspective view illustrating a conveying device during image formation (during printing).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Printer 50, 150, 250 Conveying device 52 Endless belt 66 Pressure roller 70 Lever 72 Fixed shaft 74 Moving shaft 76 Pressure spring 78 Base 80 Fixed shaft 82, 152 Cam

Claims (10)

In a conveying apparatus that places and conveys a recording medium on an endless belt that rotates in a predetermined rotation direction,
A conveying apparatus comprising a tension adjusting mechanism for adjusting a tension for tensioning the endless belt. The tension adjusting mechanism is
A predetermined tension is applied to the endless belt while the endless belt is rotating, and a tension applied to the endless belt is set to be less than the predetermined tension while the endless belt is stopped. The transport apparatus according to claim 1. The tension adjusting mechanism is
The conveying apparatus according to claim 1 or 2, wherein the tension is continuously adjusted. The tension adjusting mechanism is
The conveying apparatus according to claim 1 or 2, wherein the tension is adjusted stepwise. A driving roller that is rotated by a driving force transmitted from a predetermined driving source, and a driven roller that is disposed away from the driving roller;
5. The conveying device according to claim 1, wherein the endless belt is stretched between the driving roller and the driven roller. 6. The endless belt is composed of a plurality of endless belts arranged in a direction orthogonal to the rotation direction,
The conveying device according to any one of claims 1 to 5, wherein the tension adjusting mechanism is configured to individually adjust tensions of the plurality of endless belts. The tension adjusting mechanism is
A pressure roller for pressing the inner peripheral surface of the endless belt toward the outside;
7. A pressing means for pressing the pressure roller against the inner circumferential surface of the endless belt at a predetermined timing to pressurize the inner circumferential surface. The transfer device according to item. The pressing means is
Levers for supporting both longitudinal ends of the pressure roller;
A pedestal extending away from the lever and extending in a longitudinal direction of the lever;
A biasing means that biases the longitudinal end of the lever and the longitudinal end of the pedestal to approach each other;
The conveyance device according to claim 7, further comprising a cam that presses the pedestal at a predetermined timing so that one end in the longitudinal direction of the pedestal is separated from one end in the longitudinal direction of the lever. The endless belt is
9. The conveying apparatus according to claim 1, wherein a plurality of openings for adsorbing the recording medium are formed on the endless belt. The conveying device according to claim 1, further comprising a regulating member that regulates the endless belt so as not to move in a direction orthogonal to the rotation direction.

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