JPWO2014156887A1 - Inkjet recording device - Google Patents

Abstract

The ink jet recording apparatus includes a transport unit and an ink jet head. The transport unit continuously transports the long recording medium in the transport direction in a state where it is stretched. The transport unit includes a first transport roller, a first motor, a second transport roller, a second motor, and a first tension applying mechanism. The first transport roller is provided upstream of the inkjet head in the transport direction, and the second transport roller is provided downstream. A recording medium is placed on the first transport roller and the second transport roller. The first motor rotates the first transport roller in a direction corresponding to the transport direction, and the second motor rotates the second transport roller in a direction corresponding to the transport direction. The first tension applying mechanism applies tension to the recording medium in the middle of conveyance at a position between the first conveyance roller and the second conveyance roller in the conveyance direction and not facing the ejection surface on which the nozzles are formed by the inkjet head.

Description

  The present invention relates to an inkjet recording apparatus that conveys a long recording medium and ejects ink onto a recording surface of the conveyed recording medium. In this ink jet recording apparatus, the long recording medium is continuously conveyed in the conveying direction along the longitudinal direction of the recording medium.

  A technique related to an ink jet recording apparatus has been proposed. Patent Document 1 discloses an ink jet printer. This ink jet printer is an apparatus for forming an image on a recording medium. When forming an image, UV ink is ejected as droplets toward a recording medium that is continuously conveyed without stopping. The recording medium is a belt-like web. The ink jet printer includes a web conveyance device and an image forming unit. The web conveyance device conveys a recording medium. The web conveyance device includes an original winding roller, a plurality of driven rollers, a winding roller, and a tension adjusting roller. The image forming unit forms an image on the recording medium conveyed by the web conveying device. The image forming unit is disposed so as to face the platen above the recording medium stretched between the two driven rollers. The two driven rollers described above are provided as follows. That is, the first driven roller is provided closer to the original winding roller than the image forming unit. The second driven roller is provided on the winding roller side from the image forming unit. In the web conveyance device, the winding roller is rotated by a driving source such as a motor. Thereby, the recording medium is pulled out from the original winding roller and conveyed to the winding roller. The tension adjusting roller is provided further on the original winding roller side than the first driven roller on the original winding roller side from the image forming unit.

JP 2004-91151 A

  An image may be recorded on the recording surface of a long recording medium using an inkjet recording apparatus. Image recording using an ink jet recording apparatus is performed while transporting the recording medium in a state where the recording surface of the recording medium faces the ejection surface. The ejection surface is the surface of the inkjet head on which nozzles that eject ink are formed. Assume that a configuration of a part of a transport unit that transports the recording medium is provided at a position facing the ejection surface. In this case, ink may adhere to the configuration of the transport unit. Therefore, it may be necessary to clean the transporting portion to which the ink has adhered. The following conveyance unit can be considered. That is, the transport unit transports the recording medium in a state of being stretched between the upstream side and the downstream side of the ink jet head in the transport direction. According to this conveyance part, it is thought that the contamination by the ink as mentioned above can be suppressed. However, it is necessary to transport the recording medium so that the recording surface of the recording medium is appropriately arranged with respect to the ejection surface. For example, when the recording medium is conveyed in a bent state, the gap between the ejection surface and the recording medium (recording surface) becomes non-uniform. If the gap is non-uniform, it may not be possible to record an image of a suitable quality as compared to a uniform case.

  An object of the present invention is to provide an ink jet recording apparatus capable of applying a tension to a long recording medium and recording an image of suitable quality.

  One aspect of the present invention is transported by a transport unit that continuously transports a long recording medium in a transported direction along the longitudinal direction of the recording medium in a stretched state. An ink jet head on which a nozzle for discharging ink is formed on a recording surface of the recording medium, and the transport unit is provided upstream of the ink jet head in the transport direction, and the recording medium is laid over the first A transport roller, a first motor that rotates the first transport roller in a direction corresponding to the transport direction, a second transport roller that is provided downstream of the inkjet head in the transport direction and on which the recording medium is laid. A second motor for rotating the second transport roller in a direction corresponding to the transport direction, and the first transport roller and the second transport roller in the transport direction. In, and, said at a position not opposed to the ejection surface of the nozzle is formed by an ink-jet head, comprising a first tension applying mechanism for applying tension to the recording medium being conveyed, and an ink jet recording apparatus.

  According to this ink jet recording apparatus, the recording is carried over the first transport roller provided on the upstream side in the transport direction from the ink jet head and the second transport roller provided on the downstream side in the transport direction from the ink jet head. The medium can be suitably transported in the transport direction. The recording medium in the state described above does not bend, and can pass through the inkjet head in a state where the gap between the ejection surface and the recording medium (recording surface) is constant. Tension can be applied to the portion of the recording medium between the first transport roller and the second transport roller. This recording medium portion can be in a tensioned state. An image can be recorded by ejecting ink onto the recording surface of the tensioned recording medium. An image of suitable quality can be recorded.

  This ink jet recording apparatus may be configured as follows. The first tension applying mechanism may apply tension to the recording medium that is being transported at a position between the first transport roller and the inkjet head in the transport direction. According to this, tension can be applied on the upstream side in the transport direction from the inkjet head, and the portion of the recording medium between the first transport roller and the second transport roller can be tightly stretched. The tension is applied using a portion of the recording medium before the image is recorded. Therefore, the recording surface of the recording medium on which the image is recorded can be maintained in a clean state. For example, when ink that is difficult to dry is used, it is possible to suppress bleeding of the ink.

  According to another aspect of the present invention, a long recording medium is continuously conveyed in a conveyance direction along a longitudinal direction of the recording medium in a state of being stretched, and is conveyed by the conveyance unit. An ink jet head on which a nozzle for discharging ink is formed on the recording surface of the recording medium, and the transport section is provided upstream of the ink jet head in the transport direction, and the recording medium is laid on the recording head. A first transport roller, a first motor for rotating the first transport roller in a direction corresponding to the transport direction, and a second transport roller provided downstream of the inkjet head in the transport direction and on which the recording medium is suspended A second motor for rotating the second transport roller in a direction corresponding to the transport direction, and the first transport roller and the inkjet head in the transport direction. A first tension applying mechanism that applies tension to the recording medium in the middle of conveyance at a position between the recording medium and the recording medium that is in the middle of conveyance on the downstream side of the second conveyance roller in the conveyance direction. And a second tension applying mechanism.

  According to this ink jet recording apparatus, the recording is carried over the first transport roller provided on the upstream side in the transport direction from the ink jet head and the second transport roller provided on the downstream side in the transport direction from the ink jet head. The medium can be suitably transported in the transport direction. The recording medium in the state described above does not bend, and can pass through the inkjet head in a state where the gap between the ejection surface and the recording medium (recording surface) is constant. Tension can be applied on the upstream side in the transport direction from the inkjet head, and the tension can be applied to the portion of the recording medium between the first transport roller and the second transport roller. This recording medium portion can be in a tensioned state. An image can be recorded by ejecting ink onto the recording surface of the tensioned recording medium. The recording medium can be pressed against the peripheral side surface of the second transport roller. Slip between the recording medium and the second conveying roller can be suppressed. An image of suitable quality can be recorded.

  In the above-described ink jet recording apparatus, the transport unit is provided to face the peripheral side surface of the first transport roller, presses the recording medium toward the first transport roller, and in a direction corresponding to the transport direction. You may make it provide the press roller which follows and rotates. According to this, the recording medium can be pressed against the peripheral side surface of the first conveying roller. Slip between the recording medium and the first conveying roller can be suppressed. The recording medium can be suitably transported in the transport direction. Tension can be suitably applied to the portion of the recording medium between the first transport roller and the second transport roller in the transport direction.

  ADVANTAGE OF THE INVENTION According to this invention, the inkjet recording device which can provide tension | tensile_strength to a elongate recording medium and can record an image of suitable quality can be obtained.

It is a front view which shows an example of an inkjet recording device. It is the figure which looked at the inkjet head from the discharge surface side in which the nozzle was formed. It is a front view which shows the other example of an inkjet recording device.

  Embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the configurations described below, and various configurations can be employed in the same technical idea. For example, some of the configurations shown below may be omitted or replaced with other configurations. Other configurations may be included.

<Inkjet recording apparatus>
The ink jet recording apparatus 10 will be described with reference to FIGS. 1 and 2. In the inkjet recording apparatus 10, a long recording medium 12 is conveyed, and an image is recorded on the recording surface 14 of the recording medium 12. In this embodiment, the ink colors used for image recording are four colors of yellow, magenta, cyan, and black. The ink color may be other colors and the number of colors. Examples of the recording medium 12 include a fabric.

  As shown in FIGS. 1 and 2, the ink jet recording apparatus 10 includes a transport unit 20, a recording unit 60, and a control device 90. The transport unit 20 continuously transports the recording medium 12 along the longitudinal direction of the recording medium 12. In the present embodiment, the direction in which the recording medium 12 is transported by the transport unit 20 is referred to as “transport direction”. The transport direction is a direction along the longitudinal direction of the recording medium 12. The recording medium 12 conveyed by the conveyance unit 20 passes through the recording unit 60 during conveyance. The other description regarding the conveyance part 20 is mentioned later.

  The recording unit 60 includes an inkjet head 64Y, an inkjet head 64M, an inkjet head 64C, an inkjet head 64K, and a carriage 72. The inkjet head 64Y is a line-type inkjet head that discharges yellow ink. The inkjet head 64M is a line-type inkjet head that discharges magenta ink. The inkjet head 64C is a line-type inkjet head that discharges cyan ink. The inkjet head 64K is a line-type inkjet head that discharges black ink.

  The inkjet heads 64Y, 64M, 64C, and 64K have the same configuration. In the present embodiment, the inkjet heads 64Y, 64M, 64C, and 64K are not distinguished or are collectively referred to as “inkjet head 64”. Each color ink is stored in an ink tank (not shown) for each color. The ink of each color stored in the ink tank of each color flows through the ink flow path (not shown) of each color and is supplied to the ink jet head 64 of the corresponding color.

  In the line-type inkjet head 64, nozzles 68 that eject ink of each color are arranged in a direction orthogonal to the transport direction. For example, in the inkjet head 64, the nozzles 68 are formed in a range W2 that is equal to or greater than the width W1 of the recording medium 12 in a direction orthogonal to the transport direction (see FIG. 2). In FIG. 2, the recording medium 12 is illustrated by a two-dot chain line. The direction orthogonal to the transport direction coincides with the short direction of the recording medium 12. The short side direction of the recording medium 12 is the width direction of the recording medium 12.

  An ink jet head 64 for each color is mounted on the carriage 72. As shown in FIGS. 1 and 2, the inkjet heads 64 </ b> Y, 64 </ b> M, 64 </ b> C, and 64 </ b> K are arranged adjacent to each other in the transport direction and mounted on the carriage 72. In the example shown in FIG. 1 and the like, the inkjet head 64Y is provided on the most upstream side in the transport direction, and the inkjet head 64K is provided on the most downstream side in the transport direction. The inkjet heads 64M and 64C are provided in the order of the inkjet head 64M and the inkjet head 64C between the inkjet heads 64Y and 64K in the transport direction. The order of arrangement of the inkjet heads 64 for each color in the transport direction may be different from that shown in FIG. These arrangement orders are appropriately determined in consideration of various conditions.

  When an image is recorded on the recording medium 12 by the ink jet recording apparatus 10, each color ink is ejected toward the recording medium 12 from the nozzles 68 formed in the ink jet heads 64 </ b> Y, 64 </ b> M, 64 </ b> C, and 64 </ b> K. The inks of the respective colors ejected from the nozzles 68 of the inkjet heads 64Y, 64M, 64C, and 64K land on the recording surface 14 of the recording medium 12. An image is recorded on the recording surface 14 by the landed ink of each color.

  The control device 90 includes a control unit 92 and an input / output unit 94. The control unit 92 executes computer programs for various processes executed by the inkjet recording apparatus 10. The control unit 92 controls the inkjet recording apparatus 10 by executing the computer program described above. The control unit 92 controls the ejection of ink of each color from the nozzles 68 formed on the inkjet head 64 for each color. The ejection of each color ink by the inkjet head 64 is controlled according to image data corresponding to an image recorded by the inkjet head 64. The control unit 92 acquires the detection signal from the detection unit 55 via the input / output unit 94. The controller 92 outputs a speed command to the second motor 52 based on the acquired detection signal. An example of the detection unit 55 is a rotary encoder. Such recording control and speed control are known control techniques. Therefore, the other description regarding these each control is abbreviate | omitted.

  The input / output unit 94 is a connection interface that connects a predetermined configuration of the inkjet recording apparatus 10 including the above-described units to the control device 90. Various signals (commands) are output from the control device 90 via the input / output unit 94. Various signals output from the predetermined configuration described above are input to the control device 90 via the input / output unit 94. When an information processing apparatus such as a personal computer is connected to the inkjet recording apparatus 10, the input / output unit 94 includes a connection interface for connection with the information processing apparatus. The image data described above may be input from the information processing apparatus to the inkjet recording apparatus 10.

  In addition to the configuration described above, the inkjet recording apparatus 10 includes a supply unit and a collection unit (not shown). The recording medium 12 is set in the supply unit. The recording medium 12 set in the supply unit is sent out from the supply unit. The recording medium 12 sent from the supply unit is transported in the transport direction by the transport unit 20. Images are recorded on the recording surface 14 of the recording medium 12 conveyed by the conveying unit 20 by the inkjet heads 64Y, 64M, 64C, and 64K. Thereafter, the recording medium 12 that has passed through the third conveyance roller 34 of the conveyance unit 20 is collected by the collection unit.

  In addition, the inkjet recording apparatus 10 may include a drying unit (not shown). The drying unit dries the recording medium 12 on which the image is recorded on the recording surface 14. In this case, the recording medium 12 that has passed through the third transport roller 34 passes through the drying unit, and is then collected by the collection unit. The supply unit, the recovery unit, and the drying unit have the same configuration as the supply unit, the recovery unit, and the drying unit that are included in a known inkjet recording apparatus. The other description regarding a supply part, a collection | recovery part, and a drying part is abbreviate | omitted. You may make it provide a dancer roller in the area from the supply part to the 1st conveyance roller 22, and / or the area from the 3rd conveyance roller 34 to the collection | recovery part. This dancer roller is provided in the same manner as the first dancer roller 24 or the second dancer roller 32 of the transport unit 20, for example.

<Transport section>
The conveyance unit 20 will be described with reference to FIG. The transport unit 20 includes a first transport roller 22, a first dancer roller 24, a support roller 26, a pressing roller 28, a second transport roller 30, a second dancer roller 32, a third transport roller 34, A motor 51, a second motor 52, and a third motor 53 are provided. In the transport unit 20, a transport path is formed along each arrangement of the first transport roller 22, the first dancer roller 24, the support roller 26, the second transport roller 30, the second dancer roller 32, and the third transport roller 34. The recording medium 12 is transported in the transport direction along a transport path formed by these rollers. In FIG. 1 and FIG. 3 to be described later, the first transport roller 22, the first dancer roller 24, the support roller 26, the pressing roller 28, the second transport roller 30, the second dancer roller 32, and the third transport roller 34. The arc-shaped arrow described inside indicates the rotational direction of each of these rollers.

  The 1st conveyance roller 22, the 1st dancer roller 24, the support roller 26, and the press roller 28 are provided in an upstream area | region. As shown in FIG. 1, the upstream region is a region on the upstream side in the transport direction from the inkjet head 64 </ b> Y provided on the most upstream side in the transport direction in the recording unit 60. Regarding the arrangement of the first transport roller 22, the first dancer roller 24, and the support roller 26 in the upstream region, the first transport roller 22 is provided on the most upstream side in the transport direction, and the support roller 26 is on the most downstream side in the transport direction. Is provided. The first dancer roller 24 is provided between the first transport roller 22 and the support roller 26 in the transport direction. The pressing roller 28 is provided on the upper side of the first conveying roller 22 so as to face the peripheral side surface of the first conveying roller 22.

  The 2nd conveyance roller 30, the 2nd dancer roller 32, and the 3rd conveyance roller 34 are provided in a downstream area | region. As shown in FIG. 1, the downstream region is a region on the downstream side in the transport direction from the inkjet head 64 </ b> K provided on the most downstream side in the transport direction in the recording unit 60. Regarding the arrangement of the second conveyance roller 30, the second dancer roller 32, and the third conveyance roller 34 in the downstream region, the second conveyance roller 30 is provided on the most upstream side in the conveyance direction, and the third conveyance roller 34 is arranged in the conveyance direction. Is provided on the most downstream side. The second dancer roller 32 is provided between the second transport roller 30 and the third transport roller 34 in the transport direction.

  In the transport unit 20, the recording medium 12 is transported in a state of being bridged between the first transport roller 22 and the second transport roller 30. Tension acts on the portion of the recording medium 12 between the first conveyance roller 22 and the second conveyance roller 30. In the region between the first conveyance roller 22 and the second conveyance roller 30, the recording medium 12 is tightly tensioned. The portion of the recording medium 12 between the first conveyance roller 22 and the second conveyance roller 30 includes the portion of the recording medium 12 that faces the ejection surface 70.

  In the transport unit 20, both the support roller 26 and the second transport roller 30 are provided in a state in which the height of the peripheral side surface is a height H from the reference surface (see FIG. 1). In the present embodiment, the reference surface is a floor surface on which the ink jet recording apparatus 10 is installed. Therefore, when the recording medium 12 is conveyed in the conveying direction between the support roller 26 and the second conveying roller 30 in the conveying direction, the recording surface 14 of the recording medium 12 is in a horizontal state. The recording medium 12 is conveyed in a region facing the ejection surface 70 with the gap G being constant. The gap G is the distance between the ejection surface 70 and the recording medium 12. Note that the above-described gap G is the distance between the ejection surface 70 and the recording surface 14 of the recording medium 12 in detail. In the present embodiment, the height of the peripheral side surfaces of both the first transport roller 22 and the third transport roller 34 is set to the height H from the reference surface.

  The first transport roller 22 is fixed to the first rotating shaft 41. The first conveying roller 22 is in contact with the surface opposite to the recording surface 14 of the recording medium 12. The first rotating shaft 41 is connected to the first motor 51. The first motor 51 rotates the first rotation shaft 41 in a direction corresponding to the transport direction. Thereby, the first transport roller 22 rotates in a direction corresponding to the transport direction.

  The first dancer roller 24 is urged by an urging unit (not shown). For example, the first dancer roller 24 is urged downward in the vertical direction (see FIG. 1). Examples of the urging unit include a spring, a weight, and an actuator. An example of the actuator is an air cylinder. The first dancer roller 24 is provided between the first transport roller 22 and the second transport roller 30 in the transport direction and at a position that does not face the ejection surface 70. At this position, the first dancer roller 24 pulls the recording medium 12 conveyed in a state of being stretched between the first conveyance roller 22 and the second conveyance roller 30 downward in the vertical direction. The recording medium 12 reaches the first dancer roller 24 toward the lower side in the vertical direction along the peripheral side surface of the first conveying roller 22. The recording medium 12 folds the first dancer roller 24, moves upward in the vertical direction, and reaches the support roller 26. The first dancer roller 24 is rotated in accordance with a direction corresponding to the transport direction while in contact with the recording surface 14 of the recording medium 12.

  The support roller 26 is in contact with the surface of the recording medium 12 opposite to the recording surface 14. The support roller 26 is fixed to a predetermined rotating shaft. The support roller 26 is rotated in accordance with a direction corresponding to the transport direction while being in contact with the surface of the recording medium 12 opposite to the recording surface 14. The recording medium 12 being conveyed in the conveyance direction is bent along the peripheral side surface of the support roller 26. The recording medium 12 is conveyed in the horizontal direction from the direction from the lower side to the upper side in the vertical direction.

  As described above, the recording medium 12 is pulled downward in the vertical direction by the first dancer roller 24 between the first conveying roller 22 and the support roller 26. The recording medium 12 pulled downward in the vertical direction is in a state of hanging in a U-shape therebetween (see FIG. 1). The tension applied to the recording medium 12 being transported between the first transport roller 22 and the second transport roller 30 is applied while the recording medium 12 is supported by the first transport roller 22 and the support roller 26. Is done. Accordingly, when the first conveying roller 22 and the support roller 26 apply tension to the recording medium 12 being conveyed while being stretched between the first conveying roller 22 and the second conveying roller 30, Configure the supporting mechanism. The first conveying roller 22, the support roller 26, and the first dancer roller 24 constitute a first tension applying mechanism. The first tension applying mechanism is a mechanism that applies tension to the recording medium 12 being transported at a position between the first transport roller 22 and the inkjet head 64Y in the transport direction.

  The pressing roller 28 is urged toward the first conveying roller 22 by an urging unit (not shown). In the present embodiment, the side of the first conveying roller 22 to which the pressing roller 28 is urged is the lower side in the vertical direction. The pressing roller 28 is in contact with the recording surface 14 of the recording medium 12 and presses the recording medium 12 against the peripheral side surface of the first conveying roller 22. The pressing roller 28 is fixed to a predetermined rotating shaft. The pressure roller 28 is rotated in accordance with a direction corresponding to the transport direction while being in contact with the recording surface 14 of the recording medium 12.

  The second conveyance roller 30 is fixed to the second rotation shaft 42. The second conveyance roller 30 is in contact with the surface opposite to the recording surface 14 of the recording medium 12. The second rotating shaft 42 is connected to the second motor 52. The second motor 52 rotates the second rotating shaft 42 in a direction corresponding to the transport direction. As the second motor 52, for example, a motor that can accurately control rotation, such as a servo motor, is employed. The rotation of the second motor 52 or the rotation of the second transport roller 30 is measured by the detection unit 55. The rotation of the second motor 52 is controlled according to the detection result of the detection unit 55. The second transport roller 30 rotates in a direction corresponding to the transport direction in a state where the rotation is controlled by the second motor 52. The conveyance of the recording medium 12 by the conveyance unit 20 is performed in a state where the conveyance speed and the conveyance amount are controlled in this way.

  The second dancer roller 32 is urged by an urging unit (not shown). For example, the second dancer roller 32 is urged downward in the vertical direction (see FIG. 1). Examples of the urging unit include an actuator such as a spring, a weight, or an air cylinder. The second dancer roller 32 is provided between the second transport roller 30 and the third transport roller 34 in the transport direction. At this position, the second dancer roller 32 pulls the recording medium 12 downward in the vertical direction. The recording medium 12 reaches the second dancer roller 32 in the vertical direction along the peripheral side surface of the second conveying roller 30. The recording medium 12 folds the second dancer roller 32, moves upward in the vertical direction, and reaches the third transport roller 34. The second dancer roller 32 rotates following the direction corresponding to the transport direction while in contact with the recording surface 14 of the recording medium 12.

  The recording medium 12 is twisted 180 ° in the first direction between the second conveyance roller 30 and the second dancer roller 32, and then the recording medium 12 is moved in the second direction between the second dancer roller 32 and the third conveyance roller 34. You may make it twist 180 degrees. The second direction is the opposite direction to the first direction. In this case, the second dancer roller 32 is driven and rotated in a direction corresponding to the transport direction while in contact with the surface of the recording medium 12 opposite to the recording surface 14.

  The third transport roller 34 is fixed to the third rotating shaft 43. The third transport roller 34 is in contact with the surface of the recording medium 12 opposite to the recording surface 14. The third rotating shaft 43 is connected to the third motor 53. The third motor 53 rotates the third rotation shaft 43 in a direction corresponding to the transport direction. As a result, the third transport roller 34 rotates in a direction corresponding to the transport direction. The recording medium 12 being conveyed in the conveyance direction is bent along the peripheral side surface of the third conveyance roller 34. The recording medium 12 is conveyed in the horizontal direction from the direction from the lower side to the upper side in the vertical direction.

  As described above, the recording medium 12 is pulled downward in the vertical direction by the second dancer roller 32 between the second conveyance roller 30 and the third conveyance roller 34. The recording medium 12 pulled downward in the vertical direction is in a state of hanging in a U-shape therebetween (see FIG. 1). The tension applied to the recording medium 12 that is being conveyed after the second conveying roller 30 in the conveying direction is such that the recording medium 12 after the second conveying roller 30 is supported by the second conveying roller 30 and the third conveying roller 34. It is given by. Therefore, the second transport roller 30 and the third transport roller 34 constitute a mechanism for supporting the recording medium 12 when tension is applied to the recording medium 12 transported after the second transport roller 30 in the transport direction. . The second conveyance roller 30, the third conveyance roller 34, and the second dancer roller 32 constitute a second tension applying mechanism. The second tension applying mechanism is a mechanism that applies tension to the recording medium 12 that is being transported on the downstream side in the transport direction from the second transport roller 30. The recording medium 12 is pressed against the peripheral side surface of the second transport roller 30 by the applied tension. Focusing on the support function of the third transport roller 34, the third transport roller 34 corresponds to the support roller 26 in the first tension applying mechanism.

  In the transport unit 20, the following operation may be performed. That is, the rotation of the third motor 53 may be controlled, and the position of the second dancer roller 32 in the vertical direction may be controlled accordingly. Thereby, in the conveyance part 20, the recording medium 12 can be pressed to the 2nd conveyance roller 30 with fixed force.

<Effect of this embodiment>
According to this embodiment, the following effects can be obtained.

  (1) In the conveyance unit 20, as shown in FIG. 1, the first conveyance roller 22 is provided in the upstream region, and the second conveyance roller 30 is provided in the downstream region. The first transport roller 22 is rotated in a direction corresponding to the transport direction by a first motor 51 connected to the first rotation shaft 41. The second transport roller 30 is rotated in a direction corresponding to the transport direction by a second motor 52 connected to the second rotating shaft 42. The recording medium 12 is transported in the transport direction by the transport unit 20 in a state of being stretched between the first transport roller 22 and the second transport roller 30. The first dancer roller 24 and the support roller 26 are provided on the downstream side in the transport direction from the first transport roller 22 in the upstream region. The first dancer roller 24 is provided between the first transport roller 22 and the support roller 26 in the transport direction. The recording medium 12 is supported by the first transport roller 22 and the support roller 26. The first dancer roller 24 pulls the recording medium 12 supported by the first transport roller 22 and the support roller 26 downward in the vertical direction.

  Therefore, the recording medium 12 that is stretched between the first conveyance roller 22 and the second conveyance roller 30 is suitably conveyed by the first conveyance roller 22 and the second conveyance roller 30 that rotate in a direction corresponding to the conveyance direction. be able to. The recording medium 12 does not bend and can pass through the recording unit 60 with the gap G being constant. In other words, the first dancer roller 24 pulls the recording medium 12 supported by the first conveying roller 22 and the supporting roller 26 downward in the vertical direction, thereby recording between the first conveying roller 22 and the second conveying roller 30. Tension can be applied to the portion of the medium 12. This portion of the recording medium 12 can be in a tight state. Images can be recorded by ejecting ink of each color onto the recording surface 14 of the tensioned recording medium 12. An image of suitable quality can be recorded. It is possible to apply tension to the recording medium 12 on the upstream side in the transport direction from the inkjet head 64Y so that the above-described portion of the recording medium 12 is tight. This tension is applied using the portion of the recording medium 12 before the image is recorded. Therefore, the recording surface 14 of the recording medium 12 on which the image is recorded can be maintained in a clean state. For example, even when ink that is difficult to dry is used and ink bleeding or the like is likely to occur, it is not necessary to take special measures for this.

  (2) The pressing roller 28 presses the recording medium 12 against the peripheral side surface of the first conveying roller 22 as shown in FIG. The 2nd dancer roller 32 and the 3rd conveyance roller 34 are provided in the downstream of the conveyance direction from the 2nd conveyance roller 30 among downstream areas. The second dancer roller 32 is provided between the second transport roller 30 and the third transport roller 34 in the transport direction. The recording medium 12 is supported by the second conveyance roller 30 and the third conveyance roller 34. The second dancer roller 32 pulls the recording medium 12 supported by the second conveyance roller 30 and the third conveyance roller 34 downward in the vertical direction. Therefore, slippage between the recording medium 12 and the first conveying roller 22 can be suppressed. Slip between the recording medium 12 and the second conveying roller 30 can be suppressed. The recording medium 12 can be suitably transported in the transport direction. Tension can be applied to the portion of the recording medium 12 between the first conveyance roller 22 and the second conveyance roller 30 in the conveyance direction.

<Modification>
This embodiment can also be performed as follows. Each modification shown below can also be employed in combination with other modifications as appropriate.

  (1) In the above description, the inkjet recording apparatus 10 in which the recording unit 60 includes the line-type inkjet head 64 has been described as an example (see FIGS. 1 and 2). The transport unit 20 can also be employed in a serial type ink jet recording apparatus. The serial type ink jet recording apparatus is a type of ink jet recording apparatus that performs image recording while reciprocating a recording unit in a main scanning direction. The recording unit is configured by mounting an inkjet head for each color on a carriage. The ink jet heads for each color are mounted on the carriage in a state of being adjacent to each other in the main scanning direction. The main scanning direction is a direction orthogonal to the transport direction. The main scanning direction coincides with the short direction of the recording medium 12. In the serial type ink jet recording apparatus, the transport unit 20 intermittently transports the recording medium 12 continuously in the transport direction. In the serial type ink jet recording apparatus, the recording unit passes over the recording surface 14. The ink for each color is ejected from the nozzles formed on the ink jet head for each color at a predetermined timing when the ejection surface faces the recording surface 14.

  (2) In the above description, the conveyance unit 20 in which the first dancer roller 24 is provided at a predetermined position in the upstream region downstream of the first conveyance roller 22 in the conveyance direction has been described as an example (see FIG. 1). The first dancer roller 24 may be provided at a predetermined position in a downstream region that is upstream in the transport direction from the second transport roller 30. In this case, the support roller 26 is also provided in the downstream region. Specifically, the support roller 26 is provided between the inkjet head 64K and the second transport roller 30 in the transport direction. The first dancer roller 24 is provided between the support roller 26 and the second transport roller 30 in the transport direction. After passing through the inkjet head 64K, the recording medium 12 reaches the first dancer roller 24 toward the lower side in the vertical direction along the peripheral side surface of the support roller 26. The recording medium 12 folds the first dancer roller 24, moves upward in the vertical direction, and reaches the second transport roller 30. The first conveying roller 22 and the supporting roller 26 are both provided in a state where the height of the peripheral side surface is the height H from the reference surface, as described above.

  The recording medium 12 is twisted 180 degrees in the first direction between the support roller 26 and the first dancer roller 24, and then the recording medium 12 is rotated 180 degrees in the second direction between the first dancer roller 24 and the second transport roller 30. You may make it twist. As described above, the second direction is opposite to the first direction. Thereby, it is possible to prevent the recording surface 14 immediately after the image is recorded by the ink jet heads 64Y, 64M, 64C, and 64K from coming into contact with the peripheral side surface of the first dancer roller 24. For example, even when ink that does not easily dry is used and / or when ink bleeding or the like is likely to occur, deterioration of the quality of the image recorded on the recording surface 14 of the recording medium 12 can be prevented. The quality of the image recorded on the recording surface 14 of the recording medium 12 can be maintained.

  (3) In the above description, the conveyance unit 20 that rotates following the direction corresponding to the conveyance direction with the support roller 26 in contact with the surface opposite to the recording surface 14 of the recording medium 12 has been described as an example ( (See FIG. 1). You may make it connect a motor to the rotating shaft to which the support roller 26 is fixed. This motor rotates the rotating shaft in a direction corresponding to the conveying direction. As a result, the support roller 26 rotates in a direction corresponding to the transport direction. The conveyance unit 20 in which the third conveyance roller 34 rotates in the direction corresponding to the conveyance direction via the third motor 53 has been described as an example (see FIG. 1). The third motor 53 may be omitted. In this case, the third conveyance roller 34 is rotated in a direction corresponding to the conveyance direction while being in contact with the surface opposite to the recording surface 14 of the recording medium 12.

  (4) In the above description, the configuration in which the recording medium 12 is supported by the first transport roller 22 and the support roller 26 has been described as an example (see FIG. 1). In this configuration, the first dancer roller 24 is provided between the first transport roller 22 and the support roller 26 in the transport direction. The first dancer roller 24 pulls the recording medium 12 downward in the vertical direction at the position described above. Thereby, tension is applied to the recording medium 12. As shown in FIG. 3, the transport unit 20 may have a configuration in which a support roller 27 is provided between the first transport roller 22 and the first dancer roller 24 in the transport direction. As with the support roller 26, the support roller 27 is fixed to a predetermined rotation shaft. The support roller 27 rotates following a direction corresponding to the transport direction in contact with the surface of the recording medium 12 opposite to the recording surface 14. In the example shown in FIG. 3, the first transport roller 22, the support rollers 26 and 27, the second transport roller 30, and the third transport roller 34 are all provided with a height H from the reference surface.

  The two support rollers 26 and 27 are mechanisms for supporting the recording medium 12 when tension is applied to the recording medium 12 being conveyed in a state of being stretched between the first conveying roller 22 and the second conveying roller 30. Configure. The two support rollers 26 and 27 and the first dancer roller 24 constitute a first tension applying mechanism. The first tension applying mechanism is a mechanism that applies tension to the recording medium 12 being transported at a position between the first transport roller 22 and the inkjet head 64Y in the transport direction. The two support rollers 26 and 27 and the first dancer roller 24 are in a predetermined position in the downstream region on the upstream side in the transport direction from the second transport roller 30 as in the case of “(2)” in the above-described modification. May be provided as appropriate. Each inkjet recording apparatus 10 shown in FIGS. 1 and 3 is the same except that the conveyance unit 20 includes a support roller 27. Therefore, the other description regarding the inkjet recording device 10 shown in FIG. 3 is abbreviate | omitted.

DESCRIPTION OF SYMBOLS 10 Inkjet recording device 12 Recording medium 14 Recording surface 20 Conveyance part 22 1st conveyance roller 24 1st dancer roller 26, 27 Support roller 28 Pressing roller 30 2nd conveyance roller 32 2nd dancer roller 34 3rd conveyance roller 41 1st rotating shaft 42 Second rotating shaft 43 Third rotating shaft 51 First motor 52 Second motor 53 Third motor 55 Detection unit 60 Recording unit 64, 64Y, 64M, 64C, 64K Inkjet head 68 Nozzle 70 Discharge surface 72 Carriage 90 Control device 92 Control Part 94 I / O part G Gap H Height W1 Width W2 Range

Claims (4)

A transport unit that continuously transports the long recording medium in the transport direction along the longitudinal direction of the recording medium in a state of being stretched;
An inkjet head having nozzles for discharging ink formed on a recording surface of the recording medium being conveyed by the conveyance unit;
The transport unit is
A first transport roller provided upstream of the inkjet head in the transport direction and on which the recording medium is laid;
A first motor for rotating the first transport roller in a direction corresponding to the transport direction;
A second transport roller provided downstream of the inkjet head in the transport direction and on which the recording medium is suspended;
A second motor for rotating the second transport roller in a direction corresponding to the transport direction;
Tension is applied to the recording medium in the middle of conveyance between the first conveyance roller and the second conveyance roller in the conveyance direction and at a position that does not face the ejection surface where the nozzles are formed by the inkjet head. An ink jet recording apparatus comprising: a first tension applying mechanism.   The inkjet recording apparatus according to claim 1, wherein the first tension applying mechanism applies tension to the recording medium in the middle of conveyance at a position between the first conveyance roller and the inkjet head in the conveyance direction. A transport unit that continuously transports the long recording medium in the transport direction along the longitudinal direction of the recording medium in a state of being stretched;
An inkjet head having nozzles for discharging ink formed on a recording surface of the recording medium being conveyed by the conveyance unit;
The transport unit is
A first transport roller provided upstream of the inkjet head in the transport direction and on which the recording medium is laid;
A first motor for rotating the first transport roller in a direction corresponding to the transport direction;
A second transport roller provided downstream of the inkjet head in the transport direction and on which the recording medium is suspended;
A second motor for rotating the second transport roller in a direction corresponding to the transport direction;
A first tension applying mechanism that applies tension to the recording medium in the middle of conveyance at a position between the first conveyance roller and the inkjet head in the conveyance direction;
An ink jet recording apparatus comprising: a second tension applying mechanism that applies tension to the recording medium that is being transported downstream of the second transport roller in the transport direction.   The conveying unit is provided to face the peripheral side surface of the first conveying roller, presses the recording medium toward the first conveying roller, and rotates in accordance with a direction corresponding to the conveying direction. An inkjet recording apparatus according to any one of claims 1 to 3, further comprising:

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