Printing device and printing method

Abstract

To provide a printer for appropriately printing at a high quality.SOLUTION: A printer 10 for printing to a medium 50 has a head part 102, a transportation driving part 108, and a control part 120. The transportation driving part 108 has a transportation roller 202 for moving the medium 50 in a prescribed transportation direction by rotating in a contact state with the medium 50, a facing roller 204 sandwiching the medium 50 between itself and the transportation roller 202, and a pressing force adjusting part 208 for adjusting the pressing force for pressing the facing roller 204 toward the transportation roller 202. In the intermediate timing of the transportation driving part 108 transporting one medium 50 continuously connected in the transportation direction, the control part 120 varies the pressing force by allowing the pressing force adjusting part 208 to adjust the pressing force.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a printing apparatus and a printing method. [Background technology]

[0002] Conventionally, in a printing device, a conveying mechanism for conveying a medium to be printed on has been widely used in which the medium is sandwiched between a conveying roller and a pinch roller (opposing roller) and the conveying roller is rotated (see, for example, Patent Document 1). Patent Document 1 also discloses a configuration using multiple pinch rollers, in which each pinch roller individually controls whether or not to press against the medium. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-218009 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a configuration using a transport roller and a pinch roller, if the clamp pressure (pressing force) with which the pinch roller is pressed against the transport roller is inappropriate, for example, an error may occur in the amount of transport of the medium. This may result in a decrease in print quality. Therefore, in order to properly perform printing with higher quality, it is desirable to press the pinch roller against the transport roller with a more appropriate clamp pressure. Therefore, an object of the present invention is to provide a printing device and a printing method that can solve the above problems. [Means for solving the problem]

[0005] The inventor of the present application has conducted intensive research into a configuration for transporting a medium using a transport roller and a pinch roller. The inventor has found that it may be preferable to change the clamp pressure at which the pinch roller is pressed against the transport roller during a printing operation. More specifically, for example, when a medium is transported using a transport roller and a pinch roller, the ratio of the portion of the medium that is on the upstream side of the transport roller and the pinch roller in the transport direction and the ratio that is on the downstream side of the transport roller and the pinch roller gradually change as the printing operation progresses. In this case, the preferable clamp pressure may change due to a change in the ratio of the weight of the medium present on the upstream side and the downstream side. In addition, as a result, for example, it is considered that an error occurs in the transport amount of the medium, even though the clamp pressure is originally intended to be constant. In response to this, the inventor of the present application has considered adjusting the clamp pressure during a printing operation to press the pinch roller against the transport roller with a more appropriate clamp pressure. In addition, by actually conducting various experiments, it has been confirmed that such a configuration allows the medium to be transported with higher accuracy.

[0006] The inventor of the present application further conducted intensive research and found the features necessary to obtain such an effect, and arrived at the present invention. In order to solve the above problems, the present invention is a printing device that prints on a medium, comprising a head unit that draws an image on the medium, a transport drive unit that transports the medium, and a control unit that controls the operation of the transport drive unit, the transport drive unit having a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction, an opposing roller that sandwiches the medium between the transport roller and the transport roller, and a pressing force adjustment unit that adjusts the pressing force that presses the opposing roller against the transport roller, and the control unit changes the pressing force by having the pressing force adjustment unit adjust the pressing force at a timing during which the transport drive unit is transporting one of the media that is continuously connected in the transport direction.

[0007] In this configuration, for example, the pressure with which the counter roller is pressed against the transport roller can be appropriately adjusted while printing is being performed on one medium. Therefore, with this configuration, for example, the counter roller can be pressed against the transport roller with a more appropriate pressure at each timing of the printing operation. This also makes it possible, for example, to transport the medium with higher accuracy and appropriately print with higher quality.

[0008] Such adjustment of the pressing force can be particularly preferably performed in a configuration in which the amount of weight change due to the change in the remaining amount of the medium upstream of the transport roller in the transport direction of the medium is large. In addition, as such a configuration, for example, a configuration using a rolled medium can be considered. In this case, the printing device further includes, for example, a feed-side medium holding unit that holds the medium wound in a roll upstream of the head unit in the transport direction. Then, the transport drive unit, for example, sandwiches the medium between the transport roller and the opposing roller and rotates the transport roller to feed the medium from the rolled medium held in the feed-side medium holding unit. In such a configuration, for example, it can be considered that the change in the remaining amount of the medium due to the progress of the printing operation is particularly large. Also, it is considered that the influence on the tension of the medium, for example, gradually changes due to the gradual change in the diameter of the part where the medium is wound in a roll. And, due to these influences, the preferable pressing force is likely to differ depending on the remaining amount of the medium. In contrast, when the pressing force is adjusted as described above, the corresponding roller can be more appropriately pressed against the transport roller at each timing of the printing operation. This also makes it possible to more appropriately transport the medium with high accuracy, for example. Configurations in which the amount of change in weight due to a change in the remaining amount of the medium is large are not limited to those using ruled media, but may also include configurations using thick media (for example, non-flexible plate-shaped media, etc.).

[0009] Also, in this configuration, the control unit causes the pressing force adjustment unit to adjust the pressing force based on, for example, the remaining amount of the medium that is located upstream of the transport roller in the transport direction among the media. With this configuration, for example, the pressing force can be appropriately adjusted. More specifically, in this case, the printing device further includes, for example, a medium remaining amount detection unit that detects the remaining amount of the medium, and a data storage unit that stores data for adjusting the pressing force. As the data for adjusting the pressing force, for example, data that associates the remaining amount of the medium with the pressing force can be used. Also, the control unit causes the pressing force adjustment unit to adjust the pressing force based on, for example, the remaining amount of the medium detected by the medium remaining amount detection unit and the data for adjusting the pressing force stored in the data storage unit. With this configuration, for example, the pressing force can be more appropriately adjusted. Also, the control unit causes the pressing force adjustment unit to adjust the pressing force so that, for example, the transport amount of the medium per unit time approaches a predetermined reference amount. With this configuration, for example, the medium can be appropriately transported with high accuracy by adjusting the pressing force.

[0010] In this configuration, the pressing force adjustment unit has, for example, a pressing member, a spring, and an adjustment member. In this case, the pressing member has, for example, one end fixed to the axis of the opposing roller, and rotates around a predetermined fulcrum to press the opposing roller against the conveying roller. As the pressing member, for example, an arm-shaped member that rotates around a fulcrum can be suitably used. In addition, the spring biases the pressing member in a direction to press the opposing roller against the conveying roller. The adjustment member adjusts the pressing force by, for example, changing the position of the other end of the pressing member to change the amount of expansion and contraction of the spring. With this configuration, for example, the pressing force can be appropriately adjusted.

[0011] In this configuration, the printing device further includes, for example, a main scanning drive unit. The main scanning drive unit, for example, causes the head unit to perform a main scanning operation in which ink is ejected while moving relatively to the medium in a preset main scanning direction. The head unit has, for example, an inkjet head that ejects ink by an inkjet method. In this case, causing the head unit to perform a main scanning operation can be considered, for example, to cause the inkjet head in the head unit to perform a main scanning operation. In this case, the transport drive unit transports the medium intermittently by transporting the medium between main scanning operations as an operation for transporting one continuously connected medium. In addition, the transport drive unit transports the medium, for example, causes the head unit to perform a sub-scanning operation in which the head unit moves relatively to the medium in a sub-scanning direction perpendicular to the main scanning direction.

[0012] In this case, the control unit, for example, causes the pressing force adjustment unit to adjust the pressing force at a timing when the medium is not moving during the operation of intermittently transporting the medium, thereby causing the pressing force adjustment unit to adjust the pressing force at a timing in the middle of the transport drive unit transporting one medium that is continuously connected in the transport direction. With this configuration, for example, it is possible to appropriately adjust the pressing force while further reducing the impact on the operation of transporting the medium. More specifically, in this case, the control unit, for example, causes the pressing force adjustment unit to adjust the pressing force at a timing when the medium is not moving between main scanning operations. With this configuration, for example, it is possible to appropriately adjust the pressing force while further reducing the impact on the operation of printing.

[0013] In addition, the adjustment of the pressing force may be performed, for example, during the execution of the main scanning operation. In this case, the control unit causes the pressing force adjustment unit to adjust the pressing force, for example, during the main scanning operation while the head unit is moving relative to the medium. With this configuration, for example, the pressing force can be adjusted efficiently during the printing operation performed by repeating the main scanning operation and the sub-scanning operation. Also, depending on the configuration of the printing device, for example, the pressing force may be adjusted during the sub-scanning operation. In this case, the control unit causes the pressing force adjustment unit to adjust the pressing force at the timing when the medium is moving in the operation of intermittently transporting the medium, so that the pressing force adjustment unit adjusts the pressing force at the timing when the transport drive unit is transporting one medium that is continuously connected in the transport direction. Even with this configuration, for example, the pressing force can be adjusted efficiently during the printing operation.

[0014] Furthermore, as a configuration of the present invention, for example, it is also possible to use a printing method or the like having the same characteristics as those described above. In this case, for example, the same effects as those described above can also be obtained. Effect of the Invention

[0015] According to the present invention, for example, high-quality printing can be appropriately performed. [Brief description of the drawings]

[0016] [Figure 1] 1A shows an example of a printing device 10 according to an embodiment of the present invention. Fig. 1A shows an example of the configuration of the main parts of the printing device 10. Fig. 1B shows an example of the configuration of a head unit 102 in a main body unit 12 of the printing device 10. [Diagram 2] 2A and 2B are diagrams illustrating a specific configuration of a pressing force adjustment unit 208 in the main body unit 12. Fig. 2(a) is a side view and a rear view of the main body unit 12. Figs. 2(b) and 2(c) are perspective views of the main body unit 12. [Diagram 3]3A is a diagram showing an example of a more detailed configuration of a main part of pressing force adjustment section 208. Fig. 3(a) is a perspective view showing a part of pressing force adjustment section 208. Fig. 3(b) is a cross-sectional view taken along a predetermined plane of the part shown in Fig. 3(a). [Figure 4] 4A and 4B are diagrams illustrating an example of a more detailed configuration of a main part of the pressing force adjustment unit 208. Fig. 4(a) is a plan view showing a part of the pressing force adjustment unit 208 as seen from a direction parallel to the width direction of the medium. Fig. 4(b) is a cross-sectional view of the part shown in Fig. 4(a) along a predetermined plane. [Diagram 5] 5A and 5B are diagrams showing an example of the configuration of a drive mechanism in pressing force adjustment unit 208. Fig. 5(a) is a perspective view and a plan view showing an example of the configuration of the drive mechanism of pressing force adjustment unit 208. Fig. 5(b) is a perspective view and a plan view showing an example of the configuration of the drive mechanism of pressing force adjustment unit 208 seen from the opposite side to Fig. 5(a). [Figure 6] 6A and 6B are diagrams for explaining in more detail the operation of adjusting the pressure force. Fig. 6A shows an example of the pressure force adjustment data stored in the data storage unit 112. Fig. 6B shows an example of the operation of adjusting the pressure force performed based on the pressure force adjustment data. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a printing device 10 according to an embodiment of the present invention. FIG. 1(a) shows an example of the configuration of the main parts of the printing device 10. FIG. 1(b) shows an example of the configuration of a head unit 102 in a main body unit 12 of the printing device 10. Except for the points described below, the printing device 10 of this example may have the same or similar features as a known printing device. For example, the printing device 10 may further have the same or similar configuration as a known printing device in addition to the configuration shown in the figure.

[0018] In this example, the printing device 10 is an inkjet printer that performs printing on a medium 50 to be printed on in a serial manner, and performs printing while sequentially paying out the medium 50 wound in a roll. The printing device 10 also includes a main body 12, a pay-out side medium holding unit 14, and a take-up side medium holding unit 16. The main body 12 is the main body of the printing device 10, and performs a printing operation on the medium 50 supplied from the pay-out side medium holding unit 14, and supplies the printed medium 50 to the take-up side medium holding unit 16. In this case, the printing operation on the medium 50 supplied from the pay-out side medium holding unit 14 can be considered to be, for example, printing on a portion of the medium 50 that is sequentially supplied from the pay-out side medium holding unit 14 while connected in the transport direction, and that has reached a predetermined position in the main body 12.

[0019] In this example, the main body 12 includes a head unit 102, a platen 104, a main scanning driver 106, a transport driver 108, a medium remaining amount detector 110, a data holder 112, and a controller 120. The head unit 102 is a unit that draws an image on the medium 50. In this example, the head unit 102 includes a plurality of inkjet heads 200y-k that eject ink by an inkjet method, as shown in FIG. 1(b). In this case, each of the inkjet heads 200y-k ejects ink of a different color from each other. More specifically, the inkjet head 200y ejects ink of Y color (yellow color). The inkjet head 200m ejects ink of M color (magenta color). The inkjet head 200c ejects ink of C color (cyan color). The inkjet head 200k ejects ink of K color (black color). In this example, each of the inkjet heads 200y-k has a plurality of nozzles arranged at different positions in a direction parallel to the transport direction. The inkjet heads 200y-k are arranged in the main scanning direction with their positions in the sub-scanning direction aligned. In this case, the sub-scanning direction is a direction parallel to the transport direction of the medium 50 in the printing device 10. The main scanning direction is a direction perpendicular to the transport direction. In a modification of the main body 12, the head unit 102 may further have inkjet heads of colors other than those described above. The inkjet heads 200y-k may be arranged in a different manner than described above.

[0020] The platen 104 is a platform-like member that holds the medium 50 facing the inkjet heads 200y-k in the head unit 102. In this example, the platen 104 holds the medium 50 supplied from the feeding-side medium holding unit 14 on its upper surface, thereby facing the inkjet heads 200y-k and the medium 50. The main scanning drive unit 106 is a drive unit that causes the head unit 102 to perform a main scanning operation. In this case, the main scanning operation can be considered to be, for example, an operation of ejecting ink while moving relatively to the medium 50 in the main scanning direction. In this example, causing the head unit 102 to perform a main scanning operation can be considered to be, for example, causing the inkjet heads 200y-k in the head unit 102 to perform a main scanning operation. In this example, the main scanning drive unit 106 causes the head unit 102 to perform a main scanning operation by fixing the position of the medium 50 in the main scanning direction and moving the inkjet heads 200y-k.

[0021] The transport drive unit 108 is a drive unit that transports the medium 50, and sequentially transports the medium 50 wound in a roll in the feed-out side medium holding unit 14, so that the portion of the medium 50 that is the target of ink ejection in the main scanning operation faces the head unit 102. In this example, the transport drive unit 108 transports the medium 50 by a predetermined transport amount each time a main scanning operation is performed, thereby sequentially changing the portion of the medium 50 that faces the head unit 102 in each main scanning operation. In addition, the transport drive unit 108 thereby causes the head unit 102 to perform a sub-scanning operation. In this case, the sub-scanning operation can be considered, for example, as an operation of moving in the sub-scanning direction relative to the medium 50. In addition, in this example, the operation of the transport drive unit 108 transporting the medium 50 can be considered, for example, as an operation of transporting the medium 50 intermittently by transporting the medium 50 between main scanning operations. The operation of transporting the medium 50 wound in a roll can be considered, for example, as an example of an operation of transporting one continuously connected medium 50.

[0022] In this example, the transport drive unit 108 includes a transport roller 202, a plurality of opposing rollers 204, a roller drive unit 206, a pressing force adjustment unit 208, and a plurality of driven rollers 210. The transport roller 202 is a roller that moves the medium 50 in the transport direction by rotating while in contact with the medium 50. In this example, the transport roller 202 is disposed between the head unit 102 and the feed-side medium holding unit 14 in the transport direction of the medium 50, and moves the medium 50 in the transport direction by rotating in a predetermined direction while sandwiching the medium 50 between the plurality of opposing rollers 204. In this case, the transport roller 202 is disposed with its axial direction parallel to the width direction of the medium 50. As the transport roller 202, for example, a roller having an axial length longer than the width of the medium 50 can be used. Furthermore, the transport roller 202 is disposed such that a portion of the outer circumferential surface of the transport roller 202 protrudes from the upper surface of the platen 104, for example, thereby moving the medium 50 along the upper surface of the platen 104.

[0023] The multiple opposing rollers 204 are rollers (pinch rollers) that sandwich the medium 50 between themselves and the transport roller 202. In this example, the opposing roller 204 is pressed against the transport roller 202 with a pressing force adjusted by a pressing force adjustment unit 208 in a state in which it can rotate in accordance with the movement of the medium 50. This causes the pressing force adjustment unit 208 to clamp the medium 50 between itself and the transport roller 202 with a clamping pressure according to the pressing force. In this example, each of the multiple opposing rollers 204 is pressed against the transport roller 202 at a different position from each other in the width direction of the medium 50.

[0024] The roller driving unit 206 is a driving unit that rotates the transport roller 202. In this example, the roller driving unit 206 rotates the transport roller 202 in response to an instruction from the control unit 120, thereby moving the medium 50 between main scanning operations. The pressing force adjustment unit 208 is configured to adjust the pressing force that presses the counter roller 204 against the transport roller 202. The specific configuration and operation of the pressing force adjustment unit 208 will be described in more detail later. The multiple driven rollers 210 are rollers for adjusting the transport path of the medium 50. In this example, each of the multiple driven rollers 210 is disposed, for example, between the transport roller 202 and the feed-side medium holding unit 14 or between the transport roller 202 and the take-up-side medium holding unit 16, thereby defining the transport path of the medium 50 at the position of each driven roller 210.

[0025] The medium remaining amount detection unit 110 is a detection unit that detects the remaining amount of the medium 50, which is the amount of the medium 50 before printing. The remaining amount of the medium 50 can be considered to be, for example, the amount of the medium 50 before passing the position of the transport roller 202. In addition, in this example, the remaining amount of the medium 50 can be considered to be, for example, the amount of the portion of the medium 50 that is located upstream in the transport direction from the transport roller 202 in the medium 50 that is transported sequentially to pass the position facing the head unit 102 while connected in the transport direction. In addition, the detection of the remaining amount of the medium 50 can be considered to be, for example, the detection of the amount corresponding to the diameter (for example, diameter) of the medium 50 wound in a roll in the feed-side medium holding unit 14. The medium remaining amount detection unit 110 detects the remaining amount of the medium 50 based on, for example, the amount of the medium 50 held in the feed-side medium holding unit 14 at the time when printing is started and the amount of the medium 50 that has passed the position of the transport roller 202 in the subsequent printing operation. In this case, the amount of medium 50 that has passed the position of the transport roller 202 may be detected, for example, based on the amount of rotation of the transport roller 202. Furthermore, the medium remaining amount detection unit 110 may detect the remaining amount of medium 50 by a method other than the above. For example, the medium remaining amount detection unit 110 may detect the remaining amount of medium 50 by measuring the diameter of the medium 50 wound in a roll in the feed-out side medium holding unit 14.

[0026] The data storage unit 112 is a storage unit that stores parameters and the like used to control the printing operation. In this example, the data storage unit 112 stores, as at least a part of such parameters, pressure adjustment data used to adjust the pressure in the pressure adjustment unit 208. In addition, as the pressure adjustment data, data that associates the remaining amount of the medium 50 with the pressure is used. As the data storage unit 112, for example, a semiconductor storage device (for example, a ROM, etc.) can be used. In this case, for example, it is preferable to use a semiconductor storage device that is rewritable.

[0027] The control unit 120 is a part including, for example, the CPU of the printing device 10, and controls the operation of each part of the printing device 10. More specifically, the printing device 10 causes the inkjet heads 200y-k to draw an image on the medium 50 by, for example, discharging ink from the inkjet heads 200y-k based on data indicating an image to be printed. The control unit 120 also controls the operation of the main scanning drive unit 106 and the transport drive unit 108, for example, to control the main scanning operation and the sub-scanning operation. Furthermore, in this example, the control unit 120 controls the operation of the pressing force adjustment unit 208 in the transport drive unit 108, thereby causing the pressing force adjustment unit 208 to adjust the pressing force with which the counter roller 204 is pressed against the transport roller 202. In this case, the control unit 120 causes the pressing force adjustment unit 208 to adjust the pressing force based on the remaining amount of the medium 50 detected by the medium remaining amount detection unit 110 and the pressing force adjustment data stored in the data storage unit 112. This also causes the control unit 120 to cause the pressing force adjustment unit 208 to adjust the pressing force based on the remaining amount of the medium 50 that is upstream of the transport roller 202 in the transport direction among one medium 50 that is continuously transported. With this configuration, for example, it is possible to appropriately control the adjustment of the pressing force performed by the pressing force adjustment unit 208. In this case, the one medium 50 that is continuously transported can be considered, for example, as a medium 50 that is composed of a series of parts that are connected in the transport direction. An example of the operation of adjusting the pressing force will be described in more detail later.

[0028] The pay-out side medium holding unit 14 is configured to hold a portion of the medium 50 before printing, and holds the medium 50 wound in a roll on the upstream side of the head unit 102 and the transport roller 202 in the main body unit 12 in the transport direction. In this case, as described above, the transport drive unit 108 in the main body unit 12 rotates the transport roller 202 while sandwiching the medium between the transport roller 202 and the opposing roller 204, thereby paying out the medium 50 from the roll-like medium 50 held in the pay-out side medium holding unit 14. The take-up side medium holding unit 16 is configured to hold a portion of the medium 50 after printing, and holds the medium 50 supplied from the main body unit 12 by winding it up on the downstream side of the head unit 102 and the transport roller 202 in the main body unit 12 in the transport direction. According to this example, for example, it is possible to appropriately print on the medium 50 wound in a roll.

[0029] As explained above, the printing device 10 may further have the same or similar configuration as a known printing device in addition to the configuration shown in the figure. For example, it is preferable that the printing device 10 further includes a fixing means for fixing the ink. In this case, for example, it is possible to use a fixing means suited to the ink to be used. More specifically, for example, when using an evaporative drying type ink, it is possible to use a heating means for drying the ink as the fixing means. Also, for example, when using an ultraviolet curing type ink, it is possible to use an ultraviolet light source as the fixing means.

[0030] Next, the configuration and operation of the pressing force adjusting unit 208 in the transport driving unit 108 will be described in more detail. FIG. 2 is a diagram for explaining a specific configuration of the pressing force adjusting unit 208 in the main body unit 12. FIG. 2(a) is a side view and a rear view of the main body unit 12. FIG. 2(b) and FIG. 2(c) are perspective views of the main body unit 12. The rear view of the main body unit 12 can be considered as a view of the main body unit 12 viewed from the upstream side in the transport direction of the medium 50, for example. In addition, in FIG. 2(a) to FIG. 2(c), examples of positions in the main body unit 12 are shown for the mounting unit 302, the drive shaft 304, the drive cam 306, and the driven cam 308, which are part of the configuration of the pressing force adjusting unit 208. In addition, examples of the specific shapes of these configurations are shown by enlarged views shown in circles in the figures.

[0031] Among these components of the pressing force adjustment unit 208, the mounting unit 302 is a component for fixing each component of the pressing force adjustment unit 208 to the housing of the main body unit 12. More specifically, in this example, the mounting unit 302 fixes each component of the pressing force adjustment unit 208 to a Y bar portion extending in the width direction (main scanning direction) of the medium. In this case, the Y bar portion can be considered as, for example, a portion having a guide rail or the like for guiding the movement of the head unit 102 (see FIG. 1) during the main scanning operation. Also, the mounting unit 302 can be considered as, for example, a part of the Y bar. The driving shaft 304 is an axis member (shaft) for driving the driving cam 306, and is disposed in a direction extending in the width direction of the medium. The driving cam 306 is a cam driven by the rotation of the driving shaft 304. The driven cam 308 is a cam that rotates according to the rotation of the driving cam 306. As will be described in more detail later, in the pressing force adjustment unit 208 of this embodiment, the pressing force with which the counter roller 204 is pressed against the transport roller 202 is changed by rotating the driven cam 308 .

[0032] As described above in relation to FIG. 1, in this example, the main body 12 has a plurality of opposing rollers 204 (see FIG. 1). The plurality of opposing rollers 204 are pressed against the conveying roller 202 at different positions in the width direction of the medium 50. Therefore, the pressing force adjustment unit 208 in this example has a plurality of driving cams 306 and a plurality of driven cams 308 corresponding to the plurality of conveying rollers 202. In this case, for example, the driving shaft 304 is rotated to rotate the plurality of driving cams 306 simultaneously. This also causes the plurality of driven cams 308 corresponding to the plurality of driving cams 306 to rotate simultaneously. With this configuration, for example, it is possible to appropriately adjust the pressing force for the plurality of opposing rollers 204.

[0033] In this case, more specifically, the pressing force adjusting unit 208 has the configuration shown in FIG. 3 and FIG. 4 at a position corresponding to each of the opposing rollers 204 (one opposing roller 204). FIG. 3 and FIG. 4 are diagrams showing an example of a more detailed configuration of the main part of the pressing force adjusting unit 208, and show an example of the configuration of the pressing force adjusting unit 208 corresponding to each opposing roller 204 together with the conveying roller 202 and the opposing roller 204. FIG. 3(a) is a perspective view showing a part of the pressing force adjusting unit 208. FIG. 3(b) is a cross-sectional view of a specific plane for the part shown in FIG. 3(a). FIG. 4(a) is a plan view showing a part of the pressing force adjusting unit 208 as seen from a direction parallel to the width direction of the medium. FIG. 4(b) is a cross-sectional view of a specific plane for the part shown in FIG. 4(a). In this example, the pressing force adjusting unit 208 has an attachment part 302 and a drive shaft 304 in common with respect to the multiple opposing rollers 204. Moreover, the pressing force adjustment unit 208 has a drive cam 306, a driven cam 308, a clamp 310, a spring 312, and a spring 314 corresponding to one opposing roller 204. Moreover, the pressing force adjustment unit 208 of this example further has a spacing mechanism 316. A part of the spacing mechanism 316 is provided corresponding to each opposing roller 204. The other part of the spacing mechanism 316 is provided in common to the multiple opposing rollers 204. Moreover, although not shown in FIGS. 3 and 4, the pressing force adjustment unit 208 of this example further has a drive mechanism that rotates the drive shaft 304.

[0034] In this example, the driving cam 306 is fixed to the driving shaft 304 so as to rotate around the driving shaft 304 as a rotation axis. This causes the driving cam 306 to rotate in accordance with the rotation of the driving shaft 304. In this case, as described above, the driven cam 308 rotates in accordance with the rotation of the driving cam 306. More specifically, in this example, the driven cam 308 is disposed so as to rotate around the driving shaft 304 as a rotation axis without being fixed to the driving shaft 304. In this case, the state in which the driven cam 308 is not fixed to the driving shaft 304 can be considered as, for example, a state in which the driving shaft 304 is passed through the driven cam 308 so as to be freely rotatable with respect to the driving shaft 304. In this example, the driven cam 308 is linked to the rotation of the driving cam 306 by being connected to the driving cam 306 by the spring 314. This causes the driven cam 308 to rotate in accordance with the rotation of the driving cam 306. In this case, the fact that the driven cam 308 is freely rotatable with respect to the drive shaft 304 can be considered to mean, for example, that the driven cam 308 is freely rotatable with respect to the drive shaft 304 when the drive cam 306 and the driven cam 308 are not connected by the spring 314. In this example, the driven cam 308 is an example of an adjustment member.

[0035] The clamp 310 is an example of a pressing member that presses the counter roller 204 against the conveying roller 202. In this example, the clamp 310 is an arm-shaped member with one end fixed to the axis of the counter roller 204, and rotates around a rotation axis 322 that serves as a fulcrum, thereby pressing the counter roller 204 against the conveying roller 202 according to the biasing force of the spring 312. In this case, the rotation axis 322 can be considered as, for example, an axis that serves as a fulcrum for the rotation of the clamp 310. More specifically, the clamp 310 in this example presses the counter roller 204 against the conveying roller 202 by receiving a biasing force from the spring 312 that lifts the clamp 310 upward on the side opposite the counter roller 204 with respect to the rotation axis 322. In this case, the upper side can be considered as, for example, a side that is separated from the medium. In addition, in this example, the clamp 310 can also be considered as, for example, a member that controls the arrangement of the counter roller 204.

[0036] The spring 312 is a spring that biases the clamp 310 in a direction to press the counter roller 204 against the conveying roller 202. In this example, the spring 312 is a coil spring, and one end of the spring 312 is fixed to the clamp 310. The other end of the spring 312 is fixed to a predetermined position where the relative position of the clamp 310 with respect to the rotation shaft 322 is fixed. With this configuration, for example, the biasing force of the spring 312 can be used to appropriately press the counter roller 204 against the conveying roller 202. As described above, the spring 314 is a spring that connects the driving cam 306 and the driving cam 306 so that the driven cam 308 rotates in accordance with the rotation of the driving cam 306.

[0037] The spacing mechanism 316 is a mechanism for switching whether or not the counter roller 204 is pressed against the conveying roller 202. In this example, the spacing mechanism 316 has a drive shaft (shaft) provided in common to the multiple counter rollers 204, and a drive cam provided for each of the counter rollers 204. The drive shaft in the spacing mechanism 316 is provided so as to extend in the width direction of the medium, for example, parallel to the drive shaft 304 that drives the drive cam 306. In addition, the drive cam in the spacing mechanism 316 is a cam that rotates according to the rotation of the drive shaft, and for example, at a certain rotation angle, contacts the clamp 310 on the side opposite to the counter roller 204 with respect to the rotation shaft 322 of the clamp 310. In addition, the drive cam of the spacing mechanism 316 changes the position of the other end of the clamp 310 so that the counter roller 204 is separated from the conveying roller 202 at a predetermined rotation position, and the counter roller 204 is pressed against the conveying roller 202 at another predetermined rotation position. With this configuration, for example, it is possible to appropriately switch between pressing the opposing rollers 204 against the conveying roller 202 all at once. In this case, the clamp 310 can also be considered to hold the opposing rollers 204 so that they can be moved toward and away from the conveying roller 202.

[0038] In the pressing force adjusting unit 208 configured as above, the position of the other end side of the clamp 310, which is the side opposite to the side holding the counter roller 204, is regulated by the driven cam 308 by contacting with the driven cam 308. In addition, the position where the clamp 310 and the driven cam 308 contact each other changes depending on the rotation angle of the driven cam 308. Therefore, in this example, when the driven cam 308 rotates at least within a range of a predetermined angle, the position of the other end of the clamp 310 changes depending on the rotation angle of the driven cam 308. In this case, as can be understood from the illustrated configuration, the amount of expansion and contraction of the spring 312 changes depending on the change in the position of the other end of the clamp 310. In addition, the pressing force pressing the counter roller 204 against the conveying roller 202 also changes due to the change in the amount of expansion and contraction of the spring 312. More specifically, in the case of the configuration shown in FIGS. 3 and 4, when the driven cam 308 is rotated (pivoted) clockwise in the drawings, the biasing force of the spring 312 is weakened in stages.

[0039] In this way, in this example, the driven cam 308 changes the position of the other end of the clamp 310 to change the amount of expansion and contraction of the spring 312, thereby adjusting the pressing force with which the counter roller 204 is pressed against the conveying roller 202. Therefore, according to this example, for example, the pressing force can be appropriately adjusted by rotating the driven cam 308. Also, in this example, by rotating the drive shaft 304 provided in common to the multiple counter rollers 204, the drive cam 306 and the driven cam 308 corresponding to each counter roller 204 can be rotated. Also, this allows the pressing force to be adjusted simultaneously for the multiple counter rollers 204. Therefore, according to this example, for example, the pressing force can be easily and appropriately adjusted for the multiple counter rollers 204.

[0040] Moreover, the pressing force adjustment unit 208 of this example can be considered to have a configuration for adjusting the pressing force in addition to the separation mechanism 316, which is a configuration for switching whether or not the counter roller 204 is pressed against the conveying roller 202. As described above, the pressing force adjustment unit 208 of this example further has a drive mechanism for rotating the drive shaft 304. As such a drive mechanism, for example, the configuration shown in FIG. 5 can be used.

[0041] Fig. 5 shows an example of the configuration of a drive mechanism in pressing force adjustment unit 208. Fig. 5(a) is a perspective view and a plan view showing an example of the configuration of the drive mechanism of pressing force adjustment unit 208 as viewed from the side where the parts shown in Fig. 3 and Fig. 4 are located. Fig. 5(b) is a perspective view and a plan view showing an example of the configuration of the drive mechanism of pressing force adjustment unit 208 as viewed from the side opposite to Fig. 5(a).

[0042] In this example, the pressing force adjustment unit 208 has a motor 332, a gear 334, an origin sensor 336, and a dog 338 as components of a drive mechanism in addition to the components shown in, for example, Figs. 3 and 4. The motor 332 is a drive source that generates power to rotate the drive shaft 304. The gear 334 is a power transmission mechanism that transmits the power of the motor 332 to the drive shaft 304. In this example, the gear 334 has multiple gears 402, 404, and 406 that mesh with each other, and rotates the drive shaft 304 according to the power generated by the motor 332 via the gears 402, 404, and 406. More specifically, in this example, the gear 402 is attached to the rotation shaft of the motor 332 and rotates according to the rotation of the rotation shaft of the motor 332. Gear 404 is a gear that connects gear 402 and gear 406, rotates according to the rotation of gear 402, and rotates gear 406 according to its own rotation. Gear 406 is attached to drive shaft 304, rotates according to the rotation of gear 404, and rotates drive shaft 304 according to its own rotation. Origin sensor 336 and dog 338 are components used to control the amount of rotation of drive shaft 304. In this example, pressing force adjustment unit 208 controls the amount of rotation of gear 406 attached to drive shaft 304 by origin sensor 336 and dog 338. With this configuration, for example, the amount of rotation of drive shaft 304 can be appropriately controlled.

[0043] With this configuration, in the pressing force adjustment unit 208 of this example, the motor 332 rotates the drive shaft 304 in response to an instruction from the control unit 120 (see FIG. 1) in the printing device 10. In this case, the control unit 120 controls the drive of the motor 332 based on, for example, pressing force adjustment data stored in the data storage unit 112 (see FIG. 1). This also makes it possible to automatically adjust the pressing force with which the counter roller 204 (see FIG. 3) is pressed against the conveying roller 202 (see FIG. 3) without relying on, for example, a user's operation. Therefore, an example of the operation for adjusting the pressing force will be described in more detail below.

[0044] FIG. 6 is a diagram for explaining the operation of adjusting the pressing force in more detail. FIG. 6(a) shows an example of pressing force adjustment data held by the data holding unit 112. As described above, in this example, the pressing force adjustment data held by the data holding unit 112 is data in which the remaining amount of the medium is associated with the pressing force. As described with reference to FIG. 3 and FIG. 4, in this example, the pressing force changes depending on the position of the other end of the clamp 310 (see FIG. 3). Therefore, in the pressing force adjustment data, as a parameter indicating the pressing force, for example, a parameter indicating the position of the other end of the clamp 310, as shown as the arm position in the figure, can be used. Also, in this example, the position of the other end of the clamp 310 changes depending on the rotation angle of the driven cam 308 (see FIG. 3). Also, the rotation angle of the driven cam 308 changes depending on the rotation angle of the drive shaft 304 (see FIG. 3). Therefore, as a parameter indicating the position of the other end of the clamp 310, for example, a parameter indicating the rotation angle of the drive shaft 304 can be used.

[0045] Also, in the printing device 10 (see FIG. 1), for example, it is considered that media made of various materials are used. In this case, it is considered that the preferable strength of the pressing force with which the opposing roller 204 is pressed against the conveying roller 202 varies depending on the medium used. For this reason, it is preferable to use data indicating the pressing force in association with the type of medium as the pressing force adjustment data. In this case, it is also considered to use data in which the remaining amount of medium and the pressing force are associated for each type of medium as shown in the figure, for example, as the pressing force adjustment data.

[0046] In FIG. 6(a), the types of media are simplified for the convenience of illustration. However, even if the material of the media is the same, it is considered that the preferable pressing force is different if the thickness of the media is different. Therefore, in the actual pressing force adjustment data, it is preferable to distinguish the types of media by considering not only the material but also the thickness. In this case, it is also possible to distinguish the types of media, for example, by the model number of the media. Also, as described above, in the pressing force adjustment data of this example, the pressing force is associated with the remaining amount of the medium. More specifically, in the example shown in FIG. 6(a), for a vinyl chloride medium, the remaining amount R1, R2, R3, etc. of the medium are associated with values ​​A1, A2, A3, etc. indicating the position of the other end of the clamp 310 (arm position) corresponding to the pressing force. Also, for a tarpaulin medium, the remaining amount R1, R2, R3, etc. of the medium are associated with values ​​B1, B2, B3, etc. indicating the position of the other end of the clamp 310.

[0047] Here, when using a medium wound in a roll upstream of the transport roller 202 as in this example, the diameter of the portion where the medium is wound in a roll will gradually change as the printing operation progresses. As a result, for example, it is considered that the influence on the tension of the medium caused by the medium held by the feeding side medium holding unit 14 (see FIG. 1) will also gradually change. In this case, it is considered that the preferable pressing force will change, for example, depending on the remaining amount of medium. Also, when using a medium wound in a roll, printing is performed on a large amount of media that is connected in series, so the change in the remaining amount of medium as the printing operation progresses will be particularly large. As a result, it is considered that the preferable pressing force will be significantly different when the remaining amount of medium is small and when it is large.

[0048] In contrast, in this example, data for adjusting the pressure that associates the remaining amount of the medium with the pressure is used, and the pressure is adjusted based on the data for adjusting the pressure, so that the pressure can be adjusted according to the remaining amount of the medium. This also makes it possible to more appropriately press the opposing roller 204 against the conveying roller 202 at each timing of the printing operation, for example. Therefore, according to this example, for example, the conveying of the medium can be more appropriately performed with high accuracy. This also makes it possible to more appropriately perform printing with high quality, for example.

[0049] In this case, the control unit 120 (see FIG. 1) of the printing device 10 causes the pressure adjustment unit 208 (see FIG. 3) to adjust the pressure based on the pressure adjustment data so that the medium transport amount per unit time approaches a predetermined reference amount. In this case, the reference amount of transport can be considered to be, for example, a transport amount determined according to a design value of the movement amount of the medium in the sub-scanning operation. In addition, the approaching of the medium transport amount to the predetermined reference amount can be considered to be, for example, adjusting the pressure amount so that the error in the medium transport amount is smaller when the counter roller 204 is pressed against the transport roller 202 with the adjusted pressure than with the pressure before adjustment. With this configuration, for example, the variation in the medium transport amount can be reduced by adjusting the pressure. In addition, this also makes it possible to appropriately transport the medium with high accuracy, for example.

[0050] Moreover, the adjustment of the pressing force using such pressing force adjustment data can be performed, for example, as shown in Fig. 6(b). Fig. 6(b) is a diagram showing an example of the operation of adjusting the pressing force performed based on the pressing force adjustment data, and shows an example of the operation of adjusting the pressing force when a vinyl chloride medium is used and the pressing force is controlled based on the pressing force adjustment data shown in Fig. 6(a). Also, in Fig. 6(b), for convenience of illustration, the pressing force is shown by the clamping pressure, which is the pressure corresponding to the pressing force. The clamping pressure can be considered to be, for example, the pressing force per unit area.

[0051] In the illustrated case, the remaining amount R1 of the medium is the remaining amount at the time when printing starts. At this time, the control unit 120 operates the pressing force adjustment unit 208 so that the position (arm position) of the other end of the clamp 310 becomes A1. More specifically, the control unit 120 adjusts the angle of the driven cam 308 (see FIG. 3) by matching the rotation angle of the drive shaft 304 (see FIG. 3) in the pressing force adjustment unit 208 to a predetermined initial position. In addition, the control unit 120 thereby also matches the position of the other end of the clamp 310 to the initial position A1 of the clamp 310. In this case, the clamp pressure that presses the counter roller 204 against the conveying roller 202 becomes a clamp force P1 that corresponds to the pressing force when the position of the other end of the clamp 310 is at A1.

[0052] Furthermore, when the printing operation progresses and the remaining amount of the medium becomes R2, the control unit 120 operates the pressing force adjustment unit 208 to change the position of the other end of the clamp 310 to A2. In this case, the control unit 120 rotates the drive shaft 304 of the motor 332 in the pressing force adjustment unit 208 to rotate the driven cam 308 and move the position of the other end of the clamp 310. As a result, the clamp pressure becomes a clamp force P2 corresponding to the pressing force when the position of the other end of the clamp 310 is A2. Then, when the printing operation progresses further and the remaining amount of the medium becomes R3, the control unit 120 operates the pressing force adjustment unit 208 to change the position of the other end of the clamp 310 to A3. In this case, too, the control unit 120 rotates the drive shaft 304 of the motor 332 in the pressing force adjustment unit 208 to rotate the driven cam 308 and move the position of the other end of the clamp 310. As a result, the clamp pressure becomes clamp force P3, which corresponds to the pressing force when the other end of clamp 310 is at position A3. As the printing operation progresses, control unit 120 further changes the position of the other end of clamp 310 in the same manner as described above, thereby further changing the clamp pressure.

[0053] In this way, in this example, the control unit 120 causes the pressing force adjustment unit 208 to adjust the pressing force at a timing during the transport of the medium. In addition, the control unit 120 thereby changes the pressing force according to, for example, the progress of the printing operation. In this case, the timing during the transport of the medium can be considered to be, for example, a timing during which the transport drive unit 108 (see FIG. 1) transports one medium that is continuously connected in the transport direction. In addition, the timing during the operation of transporting one medium that is continuously connected can be, for example, any timing in a series of operations in which the medium is transported intermittently by performing a sub-scanning operation between main scanning operations. According to this example, for example, the pressing force for pressing the counter roller 204 against the transport roller 202 can be appropriately adjusted while printing is being performed on one medium. In addition, for example, at each timing of the printing operation, the counter roller 204 can be pressed against the transport roller 202 with a more appropriate pressing force. In this case, by adjusting the pressure, for example, it is possible to transport the medium with higher accuracy and appropriately perform printing with higher quality.

[0054] Here, as described above, in this example, the printing device 10 performs a sub-scanning operation between main scanning operations to intermittently transport the medium. In this case, the operation of changing the pressing force may be performed, for example, at a timing when the medium is not moving. More specifically, in this case, the control unit 120 causes the pressing force adjustment unit 208 to adjust the pressing force at a timing when the medium is not moving in the operation of intermittently transporting the medium while the transport drive unit 108 is transporting one medium that is continuously connected in the transport direction. Such an operation can be considered, for example, as an operation of causing the pressing force adjustment unit 208 to adjust the pressing force at a timing other than when the sub-scanning operation is being performed. In addition, causing the pressing force adjustment unit 208 to adjust the pressing force can be considered, for example, as causing the pressing force adjustment unit 208 to rotate the drive shaft 304. With this configuration, for example, it is possible to appropriately adjust the pressing force while appropriately reducing the influence on the operation of transporting the medium.

[0055] In this case, it is possible to have the pressing force adjustment unit 208 adjust the pressing force when neither the main scanning operation nor the sub-scanning operation is being performed. In this case, the control unit 120 has the pressing force adjustment unit 208 adjust the pressing force when the medium is not moving between the main scanning operations. With this configuration, it is possible to appropriately adjust the pressing force while appropriately reducing the influence on the printing operation. It is also possible to adjust the pressing force during the main scanning operation. In this case, the control unit 120 has the pressing force adjustment unit 208 adjust the pressing force while the inkjet heads 200y to k (see FIG. 1) are moving relative to the medium during the main scanning operation. With this configuration, it is possible to efficiently adjust the pressing force during the printing operation performed by repeating the main scanning operation and the sub-scanning operation. Depending on the configuration of the printing device 10, it is also possible to adjust the pressing force during the sub-scanning operation. In this case, the control unit 120 causes the pressing force adjustment unit 208 to adjust the pressing force, for example, at the timing when the medium is moving in the operation of intermittently transporting the medium. Even with this configuration, it is possible to efficiently adjust the pressing force, for example, during the operation of printing.

[0056] Next, supplementary explanations regarding the configuration described above will be given. As described above, in this example, the control unit 120 adjusts the pressing force for pressing the counter roller 204 against the conveying roller 202 by controlling the operation of the motor 332 (see FIG. 4) in the pressing force adjustment unit 208, without the user manually operating a mechanical mechanism or the like. In this regard, for example, when the user adjusts the pressing force by manually operating a mechanical mechanism, it is necessary to adjust the pressing force intuitively, making it difficult to perform an adjustment with high reproducibility. In addition, it is also considered that it becomes difficult to perform detailed adjustment of the pressing force due to mechanical limitations, etc. In addition, in this case, it is usually difficult to adjust the pressing force in the middle of a printing operation. In contrast, in this example, by adjusting the pressing force as described above, it is possible to appropriately perform objective adjustment with high reproducibility. In addition, the configuration of the motor 332 and the gear 334 (see FIG. 4) in the pressing force adjustment unit 208 makes it possible to more appropriately perform detailed adjustment of the pressing force and change the pressing force in the middle of a printing operation. Therefore, according to this embodiment, for example, the pressing force can be adjusted more appropriately with high accuracy, and this makes it possible to provide, for example, a highly convenient printing device 10.

[0057] As described above, in this example, the pressing force adjusting unit 208 adjusts the pressing force by bringing the driven cam 308 into contact with one end of the clamp 310 that holds the counter roller 204 and the other end that is the opposite side. In this case, the driven cam 308 can be considered, for example, as a biasing force adjusting member that is rotatably provided. Also, the part of the driven cam 308 that contacts the clamp 310 can be considered, for example, as an engagement part that engages with the other end of the clamp 310. The operation of the pressing force adjusting unit 208 can be considered, for example, as an operation of adjusting the pressing force by rotating the biasing force adjusting member. Also, in this case, the biasing force adjusting member can be considered, for example, as a member that applies a moment against the biasing force of a spring that biases the clamp 310 in a direction to press the counter roller 204 against the conveying roller 202. In a modified example of the pressing force adjustment unit 208, it is possible to use, as the pressing force adjustment member, for example, a member that applies a moment to increase the pressing force of the spring that presses the clamp 310 in the direction of pressing the opposing roller 204 against the conveying roller 202.

[0058] As can be understood from the above description, according to this embodiment, for example, the pressing force for pressing the counter roller 204 against the conveying roller 202 can be appropriately adjusted by a simple mechanism. In this case, for example, the pressing force can be adjusted in multiple stages (multiple stages) set in advance. In this case, for example, the rotation angle of the driven cam 308 can be varied in multiple stages to adjust the pressing force in multiple stages. In this case, for example, the rotation angle corresponding to the multiple stages of pressing force is stored in the data storage unit 112 (see FIG. 1), so that the pressing force adjustment unit 208 can appropriately adjust the pressing force to a desired pressing force. For example, the pressing force can be adjusted in about three stages, such as strong, medium, and weak. In addition, by expanding the data stored in the data storage unit 112, it is also possible to perform more detailed multi-stage adjustment in five stages, seven stages, or more.

[0059] Also, the pressing force may be gradually weakened in stages, for example, in response to a decrease in the remaining amount of the medium. In this case, printing is started with a predetermined initial value of pressing force. Then, when the remaining amount of the medium is subsequently decreased to a predetermined amount, the pressing force adjustment unit 208 adjusts the pressing force so as to decrease the pressing force. Also, when the remaining amount of the medium is decreased to the next predetermined amount, the pressing force adjustment unit 208 adjusts the pressing force so as to further decrease the pressing force. Also, it is considered that the preferable way of changing the pressing force may differ depending on the configuration of the printing device 10, etc. Therefore, depending on the configuration of the printing device 10, the pressing force may be gradually strengthened in stages, for example, in response to a decrease in the remaining amount of the medium.

[0060] Furthermore, in a configuration using a rolled medium, when the printed medium is wound and held, it is also conceivable that the preferred pressing force may change depending on the amount of printed medium. In this case, it may be preferable to change the pressing force more gently, rather than gradually in one direction. In this case, it can be considered that the amount of printed medium increases as the remaining amount of medium before printing decreases. Therefore, in this case, too, by adjusting the pressing force based on the remaining amount of medium, it is possible to appropriately adjust to the preferred amount of pressing force at each point in the printing operation.

[0061] In addition, the pressing force with which the counter roller 204 is pressed against the conveying roller 202 may be adjusted based on a parameter other than the remaining amount of the medium. In this case, the pressing force adjustment unit 208 may adjust the pressing force based on the conveyance amount of the medium so that the conveyance amount is constant. More specifically, in this case, the printing device 10 further includes, for example, a conveyance amount detection unit that detects the conveyance amount of the medium. In addition, the conveyance amount detection unit detects the conveyance amount of the medium per unit time while the medium is moving during the sub-scanning operation. Then, the control unit 120 causes the pressing force adjustment unit 208 to adjust the pressing force so that the conveyance amount of the medium per unit time approaches a predetermined reference amount. Even in this configuration, for example, the medium can be appropriately conveyed with high accuracy.

[0062] As described above, in this example, the pressure with which the counter roller 204 is pressed against the transport roller 202 is adjusted during the transport of one medium that is continuously connected in the transport direction. This, for example, reduces the error in the transport amount of the medium, making it possible to perform printing with higher quality. In this regard, if the counter roller 204 is pressed against the transport roller 202 with a sufficiently strong pressure, it seems that errors in the transport amount are unlikely to occur even without such adjustment. However, even if the pressure is strong, if the remaining amount of the medium changes as the printing operation progresses, for example, the component in the transport direction of the total force received by the medium at the position of the transport roller 202 may change. In this case, even if the counter roller 204 is pressed against the transport roller 202 with a strong pressure, an error in the transport amount may occur. In particular, when a medium wound in a roll is used as in this example, the influence of such changes in the remaining amount of the medium is considered to be large. In addition, if the pressure is excessively strong, for example, it is considered that the medium is more likely to wrinkle or tear. Therefore, when pressing the counter roller 204 against the conveying roller 202 with a pressing force within a practical range, simply increasing the pressing force is likely to cause errors in the conveying amount. Therefore, even when considering increasing the pressing force, it is considered preferable to adjust the pressing force as in this example.

[0063] In addition, in order to prevent the force received by the medium at the position of the transport roller 202 from changing in the transport direction component, it is possible to adjust the tension of the medium on the upstream side of the transport roller 202 in the transport direction, for example. As such a configuration, for example, a tension bar that applies tension to the medium by contacting the medium can be used. However, when a rolled medium is used as in this example, even if the tension of the medium is adjusted by such a configuration, it is usually difficult to completely cancel the effect of the change in the diameter of the part where the medium is wound in a roll. Therefore, even when adjusting the tension of the medium, it is preferable to adjust the pressing force as in this example. Also, in the case of a wide-format printing device that uses a wide medium (for example, a medium with a width of 1 m or more), it is difficult to apply the same tension across the width of the medium. Therefore, in a wide-format printing device, it is particularly preferable to adjust the pressing force according to the remaining amount of the medium.

[0064] Furthermore, in the printing device 10 that does not adjust the tension using a tension bar or the like, it is particularly preferable to adjust the pressing force according to the remaining amount of the medium. In this case, by adjusting the pressing force, for example, even if the tension is not adjusted, the medium can be transported more stably. Furthermore, the adjustment of the pressing force according to the remaining amount of the medium may be used in combination with the adjustment of the tension using a tension bar or the like. In this case, the printing device 10 further includes a configuration for adjusting the tension, for example, upstream of the transport roller 202 in the transport direction. With this configuration, for example, the influence of a change in the diameter of the portion where the medium is wound in a roll can be more appropriately reduced.

[0065] As can be understood from the above explanation, the adjustment of the pressing force is particularly useful, for example, when the amount of weight change due to the change in the remaining amount of medium upstream of the transport roller 202 in the transport direction of the medium is large. From this perspective, it is also possible to use a medium having a configuration other than a medium wound in a roll. More specifically, a configuration in which the amount of weight change due to the change in the remaining amount of medium is large may be, for example, the use of a thick medium (for example, a non-flexible plate-shaped medium).

[0066] Furthermore, when a thick medium is used, if the thickness of the medium varies depending on the position, it becomes difficult to adjust the pressing force appropriately. Therefore, it is preferable to use a medium whose thickness is substantially the same at each consecutive position in the conveying direction. The substantially same thickness can be considered, for example, as the same design thickness. The same design thickness can be considered, for example, as the difference from the reference thickness being within a preset error range. Furthermore, when a thick medium is used, if the thickness of the medium changes significantly due to the pressing force of pressing the opposing roller 204 against the conveying roller 202, it may cause an error in the conveying amount. Therefore, it is preferable that the change in the thickness of the medium due to the pressing force at the portion between the opposing roller 204 and the conveying roller 202 is 10% or less (preferably 5% or less) of the thickness of the medium when no pressing force is applied. In this case, it can also be considered that the range in which the pressing force is changed is, for example, a range in which the change in the thickness of the medium is 10% or less (preferably 5% or less).

[0067] In the above, the control unit 120 has mainly described the operation of automatically adjusting the pressure based on the pressure adjustment data stored in the data storage unit 112, as the adjustment of the pressure. In contrast, the adjustment of the pressure may be performed in response to a user's instruction, for example, by the printing device 10 accepting a user's operation. In this case, the control unit 120 causes the pressure adjustment unit 208 to adjust the pressure based on the pressure adjustment data stored in the data storage unit 112 in response to a user's instruction. In this case, it is possible to use, for example, data that associates an instruction received from a user with a pressure. In addition, such pressure adjustment data can be considered to be, for example, data consisting of a plurality of association data that associates a pressure corresponding to the position of the other end of the clamp 310 with strength information of the pressure shown to the user. In this case, the operation of the pressure adjustment unit 208 can be considered to be, for example, an operation of changing the position of the other end of the clamp 310 based on a strength specification of the pressure from the user. [Industrial Applicability]

[0068] The present invention can be suitably used in, for example, a printing device. [Explanation of symbols]

[0069] 10...printing device, 102...head section, 104...platen, 106...main scanning drive section, 108...conveyance drive section, 110...medium remaining amount detection section, 112...data holding section, 12...main body section, 120...control section, 14...feed-out side medium holding section, 16...take-up side medium holding section, 200...inkjet head, 202...conveyance roller, 204...opposing roller, 206...roller drive section, 208 Pressing force adjusting section, 210, driven roller, 302, mounting section, 304, drive shaft, 306, drive cam, 308, driven cam, 310, clamp, 312, spring, 314, spring, 316, spacing mechanism, 322, rotating shaft, 332, motor, 334, gear, 336, origin sensor, 338, dog, 402, gear, 404, gear, 406, gear, 50, medium

Claims

1. A printing device that prints on a medium, a head unit for drawing an image on the medium; A transport drive unit that transports the medium; A control unit that controls the operation of the transport drive unit; Equipped with The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having the control unit changes the pressing force by causing the pressing force adjustment unit to adjust the pressing force at a timing during which the conveyance drive unit is conveying one of the media that is continuously connected in the conveyance direction; The printing device is further characterized in that the control unit causes the pressure adjustment unit to adjust the pressure based on the remaining amount of the medium that is upstream of the transport roller in the transport direction.

2. a medium remaining amount detection unit that detects a remaining amount of the medium; a data storage unit that stores pressure adjustment data that associates the remaining amount of the medium with the pressure; Further comprising: The printing device according to claim 1, characterized in that the control unit causes the pressure adjustment unit to adjust the pressure based on the remaining amount of the medium detected by the medium remaining amount detection unit and the pressure force adjustment data stored in the data storage unit.

3. A printing device for printing on a medium, comprising: a head unit for drawing an image on the medium; A transport drive unit that transports the medium; A control unit that controls the operation of the transport drive unit; a main scanning drive unit that causes the head unit to perform a main scanning operation in which the head unit ejects ink while moving relatively to the medium in a preset main scanning direction; Equipped with The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having the control unit changes the pressing force by causing the pressing force adjustment unit to adjust the pressing force at a timing during which the conveyance drive unit is conveying one of the media that is continuously connected in the conveyance direction; the transport drive unit transports the medium intermittently by transporting the medium between the main scanning operations as the operation of transporting one of the continuously connected media; The control unit causes the pressure adjustment unit to adjust the pressure at a timing when the medium is not moving during the operation of intermittently transporting the medium, thereby causing the pressure adjustment unit to adjust the pressure at a timing when the transport drive unit is in the middle of transporting a single piece of medium that is continuously connected in the transport direction.

4. The printing apparatus according to claim 3 , wherein the control unit causes the pressure adjustment unit to adjust the pressure during intervals between the main scanning operations when the medium is not moving.

5. The printing device according to claim 3 , wherein the control unit causes the pressing force adjustment unit to adjust the pressing force while the head unit is moving relatively to the medium in the main scanning operation.

6. A printing device for printing on a medium, comprising: a head unit for drawing an image on the medium; A transport drive unit that transports the medium; A control unit that controls the operation of the transport drive unit; a main scanning drive unit that causes the head unit to perform a main scanning operation in which the head unit ejects ink while moving relatively to the medium in a preset main scanning direction; Equipped with The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having the control unit changes the pressing force by causing the pressing force adjustment unit to adjust the pressing force at a timing during which the conveyance drive unit is conveying one of the media that is continuously connected in the conveyance direction; the transport drive unit transports the medium intermittently by transporting the medium between the main scanning operations as the operation of transporting one of the continuously connected media; The control unit causes the pressure adjustment unit to adjust the pressure at a timing when the medium is moving during the operation of intermittently transporting the medium, thereby causing the pressure adjustment unit to adjust the pressure at a timing when the transport drive unit is in the middle of transporting a single piece of medium that is continuously connected in the transport direction.

7. a feed-side medium holding section that holds the medium wound in a roll upstream of the head section in the transport direction, A printing device as described in any one of claims 1 to 6, characterized in that the transport drive unit unwinds the medium from the roll-shaped medium held in the unwinding side medium holding unit by rotating the transport roller while sandwiching the medium between the transport roller and the opposing roller.

8. 8. The printing device according to claim 1, wherein the control unit causes the pressure adjustment unit to adjust the pressure so that a transport amount of the medium per unit time approaches a predetermined reference amount.

9. The pressing force adjustment unit is a pressing member having one end fixed to the shaft of the opposing roller and rotating about a predetermined fulcrum to press the opposing roller against the conveying roller; a spring that biases the pressing member in a direction in which the pressing member presses the counter roller against the conveying roller; an adjustment member that adjusts the pressing force by changing the amount of expansion and contraction of the spring by changing the position of the other end of the pressing member; 9. The printing apparatus according to claim 1, further comprising:

10. A printing method for printing on a medium, comprising: a conveyance drive unit conveys the medium, and a head unit draws an image on the medium; The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having changing the pressing force by causing the pressing force adjustment unit to adjust the pressing force at a timing during the conveyance drive unit conveying one of the media that is continuously connected in the conveyance direction; and causing the pressure adjustment unit to adjust the pressure based on a remaining amount of the medium that is located upstream of the transport roller in the transport direction among the one medium.

11. A printing method for printing on a medium, comprising: a conveyance drive unit conveys the medium, and a head unit performs a main scanning operation in which the head unit discharges ink while moving relatively to the medium in a preset main scanning direction, thereby drawing an image on the medium with the head unit; The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having The pressing force is changed by causing the pressing force adjustment unit to adjust the pressing force at a timing during the time when the conveyance drive unit is conveying one of the media that is continuously connected in the conveyance direction, and the transport drive unit transports the medium between the main scanning operations as an operation of transporting the one continuously connected medium, thereby transporting the medium intermittently; A printing method characterized by having the pressure adjustment unit adjust the pressure at a timing when the medium is not moving during an operation of intermittently transporting the medium, thereby having the pressure adjustment unit adjust the pressure at a timing when the transport drive unit is in the middle of transporting a single piece of medium that is continuously connected in the transport direction.

12. A printing method for printing on a medium, comprising: a conveyance drive unit conveys the medium, and a head unit performs a main scanning operation in which the head unit discharges ink while moving relatively to the medium in a preset main scanning direction, thereby drawing an image on the medium with the head unit; The transport drive unit is a transport roller that rotates while in contact with the medium to move the medium in a predetermined transport direction; an opposing roller that sandwiches the medium between the opposing roller and the conveying roller; a pressing force adjustment unit that adjusts a pressing force that presses the counter roller against the conveying roller; having The pressing force is changed by causing the pressing force adjustment unit to adjust the pressing force at a timing during the time when the conveyance drive unit is conveying one of the media that is continuously connected in the conveyance direction, and the transport drive unit transports the medium between the main scanning operations as an operation of transporting the one continuously connected medium, thereby transporting the medium intermittently; A printing method characterized by having the pressure adjustment unit adjust the pressure at a timing when the medium is moving during an operation of intermittently transporting the medium, thereby having the pressure adjustment unit adjust the pressure at a timing when the transport drive unit is in the middle of transporting a single piece of medium that is continuously connected in the transport direction.

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