Printing apparatus, method for controlling a printing apparatus

Abstract

To provide a printing device that can suppress cockling and wind up a medium while suppressing slack or the like, by appropriately performing heating and pressurization of the medium, in accordance with various conditions (a kind of the medium, a printing condition and an environmental condition), and a control method of a printing device.SOLUTION: A printing device 1 comprises a feeding part 20, a conveying roller 25, a printing part 40, a guide part 50, a winding-up part 60 and a control part 3. The guide part 50 has a heating part (a first heating part 81) that heats a surface contacting a printing medium (a medium M), and applies tension while making the first heating part 81 heat the printed medium M. The control part 3 controls wind-up force of the winding-up part 60, so that the tension applied to the medium M by the guide part 50 is adjusted. Further, the control part 3 controls the wind-up force of the winding-up part 60 and a heating temperature of the first heating part 81 so that the wind-up force and the heating temperature are varied in accordance with a kind of the medium M, a printing condition at the time of printing and an environmental condition.SELECTED DRAWING: Figure 1

Description

Technical Field

[0005] , , ,

[0004] , ,

[0001] The present invention relates to a printing apparatus and a control method for the printing apparatus.

Background Art

[0002] Conventionally, a printing apparatus that prints on a medium such as roll paper is known. The printing apparatus performs printing by discharging ink from a discharge head toward the medium. In such a printing apparatus, in order to dry and fix the ink discharged onto the medium so that the printed medium does not cockle due to swelling by the ink, a heating unit such as a heater is provided. In the printing apparatus of Patent Document 1, it is an issue that the drying of the ink is inhibited due to the temperature of the medium decreasing by the contact portion with which the medium comes into contact after printing, and it is disclosed that a heater is installed in the contact portion to suppress the temperature decrease of the medium.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, Patent Document 1 has a configuration in which the medium is heated by a guide unit that guides the medium to apply tension, but there is a problem that it is difficult to perform appropriate drying and winding of the medium according to various conditions (type of medium, printing conditions, environmental conditions).

Means for Solving the Problems

[0005] The printing apparatus comprises a feeding unit that feeds out a printing medium wound in a roll, a transport roller that transports the printing medium fed out from the feeding unit in the transport direction, a printing unit that applies liquid to the transported printing medium and performs printing, a guide unit that contacts the printing medium and applies tension, a winding unit that winds up the printed printing medium, and a control unit, wherein the feeding unit, the transport roller, the printing unit, the guide unit and the winding unit are arranged in this order from the upstream side in the transport direction, and the guide unit is, The device has a first heating section that heats a guide surface which is the surface in contact with the printing medium, and applies tension to the printing medium after printing while heating it with the first heating section via the guide surface, and the control unit adjusts the tension applied by the guide section to the printing medium by controlling the winding force of the winding section, and controls the winding section and the first heating section to change the winding force of the winding section and the heating temperature of the first heating section according to the type of printing medium, printing conditions at the time of printing, or environmental conditions.

[0006] A method for controlling a printing apparatus comprises a feeding unit for feeding out a printing medium wound in a roll, a transport roller for transporting the printing medium fed out from the feeding unit in a transport direction, a printing unit for applying liquid to the transported printing medium and performing printing, a guide unit for contacting the printing medium and applying tension, and a winding unit for winding up the printed printing medium after printing, wherein the feeding unit, the transport roller, the printing unit, the guide unit, and the winding unit are arranged in this order from the upstream side in the transport direction. The guide section has a heating section that heats the guide surface, which is the surface that contacts the printing medium, and applies tension to the printed printing medium after printing while heating it with the heating section via the guide surface. The printing apparatus adjusts the tension applied by the guide section to the printing medium by controlling the winding force of the winding section, and controls the winding section and the heating section to change the winding force of the winding section and the heating temperature of the heating section according to the type of printing medium, the printing conditions during printing, or the environmental conditions. [Brief explanation of the drawing]

[0007] [Figure 1] A schematic cross-sectional view showing the configuration of a printing apparatus according to an embodiment. [Figure 2] A schematic block diagram showing the electrical configuration of a printing device. [Figure 3] A flowchart illustrating an example of a printing device control method. [Figure 4] A flowchart illustrating an example of a printing device control method. [Figure 5] A flowchart illustrating an example of a printing device control method. [Modes for carrying out the invention]

[0008] 1. Embodiment Figure 1 is a schematic cross-sectional view showing the configuration of the printing apparatus 1 according to this embodiment. Figure 2 is a schematic block diagram showing the electrical configuration of the printing apparatus 1. As shown in Figure 1, the printing apparatus 1 of this embodiment is a serial-type large-format printer (LFP) that handles a long medium M, which is an example of a printing medium (hereinafter referred to as medium M).

[0009] Note that Figure 1 uses an XYZ coordinate system. The Z direction is the direction along gravity, or the vertical direction. Hereafter, this Z direction will also be referred to as the up-down direction. The X direction intersects (orthogonal in this embodiment) with the up-down direction and is the longitudinal direction of the housing 10 (width direction of the medium M). Hereafter, this X direction will also be referred to as the width direction or scanning direction. The Y direction intersects (orthogonal in this embodiment) with both the Z direction (up-down direction) and the X direction (width direction). Hereafter, this Y direction will also be referred to as the front-back direction.

[0010] In the front-to-back direction (Y direction), the front or front side of the printing device 1 is defined as the +Y direction, and the rear or back side is defined as the -Y direction. In the width direction (X direction), when the printing device 1 is viewed from the front, the left side is defined as the +X direction, and the right side is defined as the -X direction. In the up-down direction (Z direction), the top, upper, upper, and top surfaces are defined as the +Z direction, and the bottom, lower, lower, and bottom surfaces are defined as the -Z direction.

[0011] The medium M is transported from the dispensing unit 20 (described later) towards the winding unit 60. The direction in which the medium M is transported is referred to as the transport direction F. When referring to the positional relationship along the transport direction F of the medium M, the side of the dispensing unit 20 is referred to as the upstream side, and the side of the winding unit 60 is referred to as the downstream side.

[0012] The schematic configuration of the printing apparatus 1 will be explained with reference to Figures 1 and 2. The printing apparatus 1 consists of a frame 15, a feeding unit 20, transport rollers 25, a support unit 30, a printing unit 40, a guide unit 50, a winding unit 60, a pressing roller 70, a heating unit 80, a control unit 3, and the like. As shown in Figure 1, the frame 15 consists of a base frame 16 extending in the width direction, and a pair of leg frames 17 that extend in the front-rear direction integrally with the base frame 16 and are formed in the width direction to support the weight of the printing apparatus 1.

[0013] The heating unit 80, as will be described in detail later, comprises a first heating unit 81, a second heating unit 82, and a third heating unit 83. By heating the printed medium M, it quickly dries and fixes the attached ink to the medium M, suppressing bleeding and blurring. In addition, the first heating unit 81 and the second heating unit 82 flatten the medium M that has swollen and deformed due to the ink, thereby suppressing cockling.

[0014] As shown in Figure 1, the feed unit 20, transport rollers 25, support unit 30, guide unit 50, and pressure rollers 70 are fixed to the base frame 16. The winding unit 60 is fixed to the leg frame 17, etc. The printing unit 40 is installed inside a roughly rectangular prism-shaped housing 10 that is longer in the width direction and fixed to the base frame 16. The control unit 3 is provided inside the housing 10 and comprehensively controls the operation of each part of the printing device 1.

[0015] The printing device 1 is equipped with a pair of casters 18 and a pair of adjusters 19 at the lower ends of a pair of leg frames 17 that are configured in the width direction. After the printing device 1 is moved to the installation location by the casters 18, the height of the printing device 1 is adjusted (horizontal adjustment, etc.) by the adjusters 19 and then fixed to, for example, the floor.

[0016] The feeding unit 20 is provided at the lower part on the back side of the housing 10. The feeding unit 20 includes a pair of holders 22 that sandwich both ends of the core tube 21. A roll body R1 in which an unused printing medium M is wound around the core tube 21 in a roll shape is held by the holder 22. One of the holders 22 is provided with a feeding motor (not shown) that supplies a rotational force to the core tube 21. When the feeding motor is driven and rotates in the feeding direction (counterclockwise direction in Fig. 1), the core tube 21 is driven to rotate, so that the medium M is fed from the roll body R1 toward the conveying roller 25. The control unit 3 controls the feeding unit 20 (feeding motor).

[0017] A plurality of roll bodies R1 of different sizes with different widths and numbers of windings of the medium M can be loaded into the feeding unit 20 in a replaceable manner. Also, a plurality of roll bodies R1 of different types (materials) of the medium M can be loaded into the feeding unit 20 in a replaceable manner.

[0018] The support unit 30 includes a first support unit 31, a platen 32, and a second support unit 33. The first support unit 31 is provided upstream of the platen 32, and the second support unit 33 is provided downstream of the platen 32. The first support unit 31 guides the medium M fed from the feeding unit 20 to the platen 32. The second support unit 33 guides the medium M printed by the printing unit 40 to the guide unit 50 and the winding unit 60.

[0019] The platen 32 is formed with a substantially rectangular surface having the scanning direction as the longitudinal direction, and is installed at a position facing the printing unit 40 (discharge head 41). The platen 32 supports the medium M to be printed by the printing unit 40 from below. Specifically, the platen 32 sucks and supports the medium M on the upper surface of the platen 32 by the negative pressure applied to the platen 32. Thereby, the deterioration of the print quality due to the floating of the medium M is suppressed.

[0020] The conveying roller 25 conveys the medium M fed out from the feeding section 20 in the conveying direction F. The conveying roller 25 includes a driving roller 26, a driven roller 27, and a driving motor (not shown). The driving roller 26 is provided between the first support portion 31 and the platen 32. The driving roller 26 is configured to extend in a direction intersecting the conveying direction F of the medium M.

[0021] The driven roller 27 is arranged above the driving roller 26 and is configured to be movable so as to be separated from or in pressure contact with the driving roller 26. When the driving motor is driven and the driving roller 26 is rotationally driven, the medium M sandwiched between the driving roller 26 and the driven roller 27 is conveyed in the conveying direction F. The control unit 3 controls the rotation of the conveying roller 25 (driving motor).

[0022] The printing section 40 is arranged above and facing the platen 32 on the downstream side of the conveying roller 25. The printing section 40 has a discharge head 41 that discharges and adheres ink as a liquid toward the medium M supported on the upper surface of the platen 32, and a carriage 42 that is reciprocally movable in a scanning direction orthogonal to the conveying direction F of the medium M while supporting the discharge head 41.

[0023] The discharge head 41 is provided with a plurality of nozzles (not shown) and is configured to be able to discharge ink. Specifically, the discharge head 41 is configured such that a plurality of nozzles are arranged in a direction orthogonal to the scanning direction. And each discharge head 41 is installed side by side in the scanning direction for each color. The control unit 3 controls the operation of the discharge head 41.

[0024] The carriage 42 is supported so as to be able to reciprocate on two carriage shafts 46 that extend in the width direction and are installed on a carriage frame 45. In this embodiment, the carriage 42 and the carriage shafts 46 are engaged via two bearings 43 fixed to the carriage 42. The carriage 42 then moves along the carriage shafts 46 by a carriage motor (not shown). The bearings 43 are configured as so-called ball bearings. The control unit 3 controls the operation of the carriage 42 (carriage motor).

[0025] In the printing apparatus 1 of this embodiment, a discharge operation in which ink is discharged from the discharge head 41 as ink droplets while the discharge head 41 is moved in the scanning direction (X direction), and a transport operation in which the transport roller 25 transports the medium M by a predetermined amount in the transport direction F, are repeated alternately to form dots on the medium M and print a predetermined image on the medium M. In this embodiment, the ejection head 41 is exemplified as a serial head type ejection head mounted on a reciprocating carriage 42 that ejects ink while moving in the scanning direction. However, the ejection head 41 may also be a line head type ejection head that ejects ink while extending in the scanning direction and remaining fixed.

[0026] The winding section 60 is installed downstream of the guide section 50, which will be described later. The winding section 60 is equipped with a pair of holders 62 that sandwich both ends of the core tube 61. The holders 62 hold a roll body R2, which is formed when the medium M printed in the printing section 40 is wound onto the core tube 61. One of the holders 62 is equipped with a winding motor (not shown) that supplies rotational force to the core tube 61. When the winding motor is driven and rotates in the winding direction (counterclockwise in Figure 1), the core tube 61 rotates in response, causing the medium M, which has passed through the guide section 50, to be wound onto the core tube 61, forming the roll body R2.

[0027] In this embodiment, the winding unit 60 winds the medium M in synchronization with the transport operation of the transport roller 25 under the control of the control unit 3. Furthermore, the torque of the roll body R2 is optimized and the tension of the medium M is adjusted according to the speed at which the medium M is fed out, the inertia (moment of inertia) of the winding unit 60, the type of medium M described later, the printing conditions during printing, and environmental conditions.

[0028] The guide section 50 is installed downstream of the second support section 33 and upstream of the winding section 60, and guides the printed medium M toward the winding section 60. The guide section 50 is a hollow cylindrical shape and consists of a cylindrical section 51 that is longer than the width of the medium M, and a first heating section 81 installed inside the cylindrical section 51. The guide section 50 is installed on the base frame 16 with both ends of the cylindrical section 51 supported and fixed by a holding section (not shown).

[0029] In this embodiment, the guide portion 50 does not rotate. The guide portion 50 has a guide surface, which is the front outer circumferential surface of the cylindrical portion 51, that abuts against the medium M, and applies appropriate tension to the printed medium M as it is transported in the transport direction F by the drive of the winding portion 60. Therefore, the printed medium M is transported by sliding within the guide portion 50 while a predetermined tension is applied to the front outer circumferential surface of the cylindrical portion 51. The cylindrical portion 51 of the guide portion 50 abuts against the surface of the printed medium M opposite to the printed surface.

[0030] The tension that the guide section 50 applies to the medium M is generated by the winding force (rotational force) supplied to the core tube 61 by the winding motor of the winding section 60. In other words, the control unit 3 adjusts the tension that the guide section 50 applies to the medium M by controlling the winding force of the winding section 60 (specifically, by controlling the winding motor).

[0031] The material of the cylindrical portion 51 can be, for example, aluminum, which has good thermal conductivity as a metal component. Furthermore, the outer surface of the aluminum is subjected to surface treatment such as anodizing to improve strength and corrosion resistance, as well as wear resistance and smoothness. As a result, the heat generated by the first heating unit 81 installed inside the cylindrical portion 51 can be efficiently transferred to the medium M.

[0032] The first heating unit 81 is, for example, an infrared heater that heats using infrared or far-infrared rays. In addition to an infrared heater, the first heating unit 81 can also be, for example, a sheathed heater having a heating element (nichrome wire) inside, or a ceramic heater using ceramics as the heating element. The first heating unit 81 is connected to a heating drive unit (not shown) which is located outside the guide unit 50. The first heating unit 81 is heated by the driving of the heating drive unit, which heats the cylindrical unit 51 from the inside, thereby heating the medium M that is in contact with the outer surface of the cylindrical unit 51. The control unit 3 adjusts the heating temperature of the first heating unit 81 that heats the printed medium M by controlling the heating drive unit.

[0033] The pressure roller 70 is installed on the upper part of the roll body R2 of the winding section 60 and rotates in accordance with the rotation of the winding section 60. The pressure roller 70 is cylindrical and consists of a roller section 71 which is longer than the width of the medium M, a rotating shaft 72 which rotates the roller section 71, and a second heating section 82 which is installed inside the roller section 71.

[0034] Furthermore, the pressing roller 70 is equipped with a pressing mechanism (not shown). The pressing mechanism rotatably holds the rotation axis 72 of the pressing roller 70 and rotatably supports both ends of the roller portion 71, causing the roller portion 71 to come into contact with the roll body R2 and press the wound medium M. The control unit 3 can adjust the pressing force applied to the roll body R2 by controlling the pressing mechanism.

[0035] The pressing roller 70, in detail, presses the outer surface of the medium M wound onto the winding section 60. The pressing roller 70 also heats the outer surface of the medium M with the second heating section 82. In this embodiment, the outer surface of the medium M to be heated is the surface opposite to the surface heated by the guide section 50. In this way, the pressing roller 70 presses the outer surface of the medium M wound onto the winding section 60 while heating it. In the pressing roller 70, the roller section 71 rotates in accordance with the rotation of the winding section 60. Hereafter, for the sake of explanation, the rotation of the roller section 71 will be referred to as the rotation of the pressing roller 70.

[0036] The material of the roller section 71 can be the same as that of the cylindrical section 51 of the guide section 50 described above; for example, aluminum, which has good thermal conductivity as a metal component, can be used. Similarly, the outer surface of the aluminum is subjected to a surface treatment such as anodizing. As a result, the heat generated by the second heating section 82 installed inside the roller section 71 can be efficiently transferred to the medium M.

[0037] The second heating unit 82, like the first heating unit 81, is an infrared heater that heats using, for example, infrared or far-infrared rays. In addition to an infrared heater, the second heating unit 82 can also be a sheathed heater having a heating element (nichrome wire) inside, or a ceramic heater using ceramics as the heating element. The second heating unit 82 is connected to a heating drive unit located outside the guide unit 50. The heating drive unit drives the second heating unit 82, which heats the roller unit 71 from the inside, thereby heating the medium M in contact with the outer surface of the roller unit 71. The control unit 3 controls the second heating unit 82 (heating drive unit) to adjust the heating temperature. The control unit 3 also controls the pressing mechanism to adjust the pressing force.

[0038] The third heating unit 83 is installed between the printing unit 40 and the guide unit 50, facing the second support unit 33 which supports the printed medium M. The third heating unit 83 heats the support surface 331 of the second support unit 33 that supports the medium M, and the medium M supported on the support surface 331. The third heating unit 83 consists of an infrared heater, a housing, a duct, a suction fan, etc., although these are not shown in the figures.

[0039] The third heating unit 83 faces the medium M, which is supported and transported by the support surface 331 of the second support unit 33, and aims to dry and fix the ink by heating the printed surface side of the medium M. The control unit 3 controls the third heating unit 83. In this embodiment, the control unit 3 controls the heating temperature of the third heating unit 83 to a fixed temperature that is initially set.

[0040] The printing device 1 is equipped with a temperature measuring unit 12 for measuring the temperature of the outside air and a humidity measuring unit 13 for measuring the humidity of the outside air, both located inside the housing 10 near the opening 11 of the housing 10.

[0041] As will be described in detail later, in this embodiment, the control unit 3 controls the tension applied to the medium M in the guide unit 50 (winding force of the winding unit 60), the heating temperature of the first heating unit 81, and the pressing force applied to the medium M by the pressing roller 70, as well as the heating temperature of the second heating unit 82, to change according to the type of medium M, the printing conditions during printing, or the environmental conditions. By adjusting the tension of the guide unit 50, the pressing force of the pressing roller 70, and the heating temperatures of the first and second heating units 81 and 82, tension, pressure, and heating are applied to the medium M, thereby straightening the medium M that has swollen and deformed due to the ink, and making it possible to wind it while suppressing cockling.

[0042] As shown in Figure 2, the printing device 1 includes an input unit 8, which provides instructions to the control unit 3 through setting and input operations. The input unit 8 may be composed of a touch panel display or the like. Furthermore, the input unit 8 may be provided separately from the printing device 1.

[0043] The control unit 3 is a control unit for controlling the printing device 1. As shown in Figure 2, the interface (I / F) unit 5 is for sending and receiving data between the input unit 8 and the control unit 3. The CPU 6 is an arithmetic processing unit for controlling the entire printing device 1. The storage unit 7 is for storing the CPU 6's program and for reserving a work area. The CPU 6 controls each part of the press roller 70 from the feed unit 20 via the control circuit 4.

[0044] In this embodiment, the memory unit 7 stores various tables. These tables include, for example, a table for the receiving layer that correlates the receiving layer with the heating temperature / pressure, a table for the ejection amount that correlates the ink ejection amount with the heating temperature / pressure, and a table for the water vapor pressure difference that correlates the water vapor pressure difference with the heating temperature / pressure.

[0045] The printing device 1 is equipped with a group of detectors (not shown), which monitor the conditions inside the printing device 1. The control unit 3 controls each component based on the detection results of the group of detectors. The temperature measuring unit 12 and the humidity measuring unit 13 are also part of the group of detectors.

[0046] Figure 3 is a flowchart showing an example of a control method for the printing apparatus 1. More specifically, Figure 3 is a flowchart for controlling the heating temperature of the first heating section 81 in the guide section 50 and the tension of the guide section 50, depending on the amount of receiving layer in the medium M.

[0047] As described above, the control unit 3 controls the heating temperature of the first heating unit 81 in the guide unit 50 and the tension of the guide unit 50 based on the amount of ink absorbed by the receiving layer on the medium M. The receiving layer is a coating layer provided on the outer surface (printing surface) of the medium M (substrate) to absorb ink and fix colorants such as dyes and pigments. By providing a receiving layer on the outer surface (printing surface) of the medium M (substrate), when ink is ejected onto the medium M, the receiving layer absorbs the ink, preventing the ink from reaching the substrate and suppressing cockling.

[0048] As shown in Figure 3, the control unit 3 determines whether the receiving amount of the receiving layer of the printing medium (medium M) is greater than a predetermined receiving capacity (step S10). Here, the receiving amount of the receiving layer corresponds to the thickness of the coated receiving layer. If the thickness of the receiving layer is set according to the type of medium M used, the receiving capacity can be set by inputting the type of medium M used from the input unit 8. Alternatively, the receiving capacity can be set by individually inputting the thickness of the receiving layer from the input unit 8.

[0049] In step S10, if the receiving capacity of the receiving layer of the medium M is greater than a predetermined receiving capacity (YES), the control unit 3 lowers the heating temperature of the first heating unit 81 to a lower temperature than the first heating temperature (step S11). The control unit 3 also reduces the tension of the guide unit 50 to a lower tension than the first tension (step S12). The tension applied to the guide unit 50 is applied by controlling the winding force of the winding unit 60, as described above.

[0050] The memory unit 7 stores a table for receiving layers that associates the receiving layer with the heating temperature / pressure. The control unit 3 refers to the table for receiving layers, reads a predetermined receiving capacity (thickness) set as the reference receiving capacity, and heats the first heating unit 81 of the guide unit 50 and applies tension so that it reaches a first heating temperature corresponding to the reference temperature and a first tension corresponding to the reference tension. The control unit 3 then refers to the table for receiving layers and sets the temperature and tension corresponding to the receiving capacity (thickness) of the input medium M.

[0051] If the receiving layer of the medium M has a receiving capacity greater than a predetermined receiving capacity, the ink ejected onto the medium M can be absorbed by the receiving layer, suppressing ink seepage into the substrate. This reduces deformation due to swelling of the medium M, making it necessary to prevent excessive heating and tension. Therefore, the control unit 3 drives the heating drive unit to lower the heating temperature of the first heating unit 81 to a temperature set by the receiving layer table, making it lower than the first heating temperature. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension is set by the receiving layer table, thereby reducing the tension of the guide unit 50 from the first tension. As a result, by applying the appropriate heating temperature and appropriate tension to the printed medium M, the medium M can be straightened to a flat state. This suppresses cockling and prevents slack during winding.

[0052] In step S10, if the receiving capacity of the receiving layer of the medium M is less than a predetermined receiving capacity (NO), the control unit 3 raises the heating temperature of the first heating unit 81 to a higher temperature than the first heating temperature (step S13). Also, the control unit 3 increases the tension of the guide unit 50 to a higher tension than the first tension (step S14).

[0053] If the receiving layer of the medium M has a receiving capacity smaller than a predetermined capacity, the receiving layer cannot absorb all of the ink ejected onto the medium M, and the ink soaks into the substrate. This causes the medium M to swell and deform easily, requiring a higher temperature and stronger tension. Therefore, the control unit 3 drives the heating drive unit to raise the heating temperature of the first heating unit 81 to a temperature set by the receiving layer table, making it higher than the first heating temperature. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension of the guide unit 50 becomes stronger than the first tension, thereby applying the appropriate heating temperature and tension to the printed medium M, allowing the medium M to be straightened to a flat state. This suppresses cockling and prevents slack during winding.

[0054] Figure 4 is a flowchart showing an example of a control method for the printing apparatus 1. More specifically, Figure 4 is a flowchart for controlling the heating temperature of the first heating section 81 in the guide section 50 and the tension of the guide section 50 based on the amount of ink discharged to adhere to the medium M.

[0055] As described above, the control unit 3 controls the heating temperature of the first heating unit 81 in the guide unit 50 and the tension of the guide unit 50 based on the amount of ink to be discharged onto the medium M (the amount of ink discharged per unit time).

[0056] As shown in Figure 4, the control unit 3 calculates the amount of ink that the printing unit 40 (ejection head 41) will eject onto the printing medium (medium M) (step S20). Specifically, the control unit 3 calculates the total amount of ink that the ejection head 41 will eject onto the medium M when printing the image, based on the image data included in the print job that has been input for printing. Then, based on the calculated total amount of ink, the control unit 3 calculates the amount of ink that the ejection head 41 will eject per unit time when printing the image.

[0057] The control unit 3 may also calculate the printing duty cycle for the medium M based on the image data included in the print job. In this case, the heating temperature and tension are controlled according to the magnitude of the printing duty cycle.

[0058] As shown in Figure 4, in step S20, when the control unit 3 calculates the amount of ink to be discharged by the printing unit 40 onto the medium M, the control unit 3 then determines whether the amount of ink to be discharged is greater than a predetermined amount (step S21). In step S21, if the amount of ink to be discharged is greater than a predetermined amount (YES), the control unit 3 raises the heating temperature of the first heating unit 81 to a higher temperature than the first heating temperature (step S22). The control unit 3 also increases the tension of the guide unit 50 to a higher tension than the first tension (step S23). The tension applied to the guide unit 50 is applied by controlling the winding force of the winding unit 60, as described above.

[0059] The memory unit 7 stores an ink discharge amount table that correlates the ink discharge amount with the heating temperature / pressure. The control unit 3 refers to the ink discharge amount table and reads a predetermined ink discharge amount that is initially set as the standard discharge amount. It then heats the first heating section 81 of the guide section 50 and applies tension so that it reaches a first heating temperature corresponding to the standard temperature and a first tension corresponding to the standard tension. The control unit 3 then refers to the ink discharge amount table and sets the temperature and tension corresponding to the calculated ink discharge amount to be deposited on the medium M.

[0060] If the amount of ink discharged onto the medium M exceeds a predetermined discharge amount, deformation due to swelling of the medium M is more likely to occur, requiring a higher temperature and stronger tension. Therefore, the control unit 3 drives the heating drive unit to raise the heating temperature of the first heating unit 81 to a temperature set from the discharge amount table, thereby raising it above the first heating temperature. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension is set from the discharge amount table, thereby increasing the tension of the guide unit 50 above the first tension. As a result, by applying the appropriate heating temperature and appropriate tension to the printed medium M, the medium M that has swollen due to the large amount of ink discharged can be straightened to a flat state, suppressing cockling and enabling winding while suppressing sagging, etc.

[0061] In step S21, if the amount of ink to be dispensed is less than a predetermined amount (NO), the control unit 3 lowers the heating temperature of the first heating unit 81 to a lower temperature than the first heating temperature (step S24). Also, the control unit 3 reduces the tension of the guide unit 50 to a lower tension than the first tension (step S25).

[0062] If the amount of ink to be applied is less than a predetermined amount, deformation due to swelling of the medium M is less likely to occur, so it is necessary to prevent excessive heating and excessive tension. For this reason, the control unit 3 drives the heating drive unit to lower the heating temperature of the first heating unit 81 to a temperature set from the discharge amount table. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension is set from the discharge amount table, thereby weakening the tension of the guide unit 50 from the first tension. As a result, by applying the appropriate heating temperature and appropriate tension to the printed medium M, excessive heating and excessive tension can be prevented and the medium M can be straightened to a flat state. Therefore, cockling can be suppressed and sagging can be suppressed during winding.

[0063] Figure 5 is a flowchart illustrating an example of a control method for the printing apparatus 1. More specifically, Figure 5 is a flowchart for controlling the heating temperature of the first heating section 81 in the guide section 50 and the tension of the guide section 50 using the pressure difference of water vapor.

[0064] Based on the ambient temperature and humidity, the control unit 3 controls the heating temperature of the first heating unit 81 in the guide unit 50 and the tension of the guide unit 50 based on the pressure difference of water vapor between the surface of the ink-coated medium M and the convection layer facing the surface.

[0065] The pressure difference of water vapor is, in detail, the difference between the saturated water vapor pressure at the surface of the medium M and the water vapor pressure (partial pressure of water vapor) in the convection layer facing the surface. This pressure difference of water vapor determines how easily water vapor diffuses; a large difference means that drying is easy, while a small difference means that drying is difficult.

[0066] More specifically, for the ink dispensed onto medium M to dry, the water in the ink must evaporate and become water vapor, which then moves. For the water vapor to move, a pressure difference in water vapor is required between the surface of medium M and the convection layer facing the surface. Since the water vapor on the surface of medium M is saturated, the pressure of the water vapor on the surface is equal to the saturated water vapor pressure. Also, the pressure of the water vapor in the convection layer facing the surface (partial pressure of water vapor) is proportional to the humidity.

[0067] Below, we will explain an example of a formula for calculating the pressure difference of water vapor. To calculate the saturated water vapor pressure on the surface of medium M, we apply the ambient temperature [°C] to the formula for calculating the saturated water vapor pressure [hPa] on the surface of medium M. Equation (1), which is the formula for calculating the saturated water vapor pressure [hPa], is shown below. Saturated water vapor pressure [hPa] = 6.11 * 10^(7.5 * temperature [°C] / (237.3 + temperature [°C])) …(1) Furthermore, the partial pressure of water vapor in the convection layer facing the surface can be calculated by multiplying the saturated water vapor pressure [hPa] by the relative humidity [%RH]. Equation (2), which is the formula for calculating the partial pressure of water vapor in the convection layer [hPa], is shown below. Partial pressure of water vapor in the convection zone [hPa] = Saturated water vapor pressure [hPa] * Relative humidity [%RH] / 100 …(2) Therefore, the pressure difference of water vapor can be obtained by subtracting the partial pressure of water vapor [hPa] from the saturated water vapor pressure [hPa]. Equation (3), which is the formula for calculating the pressure difference of water vapor [hPa], is shown below. Water vapor pressure difference [hPa] = saturated water vapor pressure [hPa] - partial pressure of water vapor [hPa] …(3)

[0068] As shown in Figure 5, the control unit 3 measures the ambient temperature (step S30). Specifically, the control unit 3 measures the ambient temperature of the printing device 1 using the temperature measuring unit 12. Next, the control unit 3 measures the ambient humidity (step S31). Specifically, the control unit 3 measures the relative humidity of the ambient air surrounding the printing device 1 using the humidity measuring unit 13.

[0069] Next, the control unit 3 calculates the saturated water vapor pressure and the partial water vapor pressure (step S32). Specifically, the control unit 3 first calculates the saturated water vapor pressure and the partial water vapor pressure based on the ambient temperature and ambient humidity using equations (1) and (2) described above. Next, the control unit 3 calculates the water vapor pressure difference (step S33). Specifically, the control unit 3 calculates the water vapor pressure difference based on the saturated water vapor pressure and the partial water vapor pressure using equation (3) described above.

[0070] Next, the control unit 3 determines whether the calculated pressure difference of the water vapor is greater than a predetermined pressure difference (step S34). In this embodiment, for example, a pressure difference of 13 [hPa] of water vapor is considered the predetermined pressure difference.

[0071] In step S34, if the pressure difference of the water vapor is greater than a predetermined pressure difference (YES), the control unit 3 lowers the heating temperature of the first heating unit 81 to a lower temperature than the first heating temperature (step S35). The control unit 3 also reduces the tension of the guide unit 50 to a lower tension than the first tension (step S36). The tension applied to the guide unit 50 is applied by controlling the winding force of the winding unit 60, as described above.

[0072] The memory unit 7 stores a water vapor pressure difference table that correlates the water vapor pressure difference with the heating temperature / pressure. The control unit 3 refers to the water vapor pressure difference table and reads the water vapor pressure difference (for example, 13 [hPa]) which is initially set as the reference pressure difference, as a predetermined pressure difference. It then heats the first heating unit 81 of the guide unit 50 and applies tension so that the first heating temperature corresponds to the reference temperature and the first tension corresponds to the reference tension. The control unit 3 then refers to the water vapor pressure difference table and sets the temperature and tension corresponding to the calculated water vapor pressure difference.

[0073] When the pressure difference of the water vapor is greater than a predetermined pressure difference, the medium M dries easily, making it less likely to deform due to swelling. Therefore, it is necessary to prevent excessive heating and excessive tension. For this reason, the control unit 3 drives the heating drive unit to set the heating temperature of the first heating unit 81 to a temperature set by the water vapor pressure difference table, making it lower than the first heating temperature. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension is set by the water vapor pressure difference table, thereby making the tension of the guide unit 50 weaker than the first tension. As a result, by applying appropriate heating and tension to the printed medium M, excessive heating and excessive tension can be prevented, and the medium M can be straightened to a flat state. Therefore, cockling can be suppressed, and sagging can be suppressed during winding.

[0074] In step S34, if the pressure difference of the water vapor is less than a predetermined pressure difference (NO), the control unit 3 raises the heating temperature of the first heating unit 81 to a higher temperature than the first heating temperature (step S37). Also, the control unit 3 increases the tension of the guide unit 50 to a higher tension than the first tension (step S38).

[0075] If the pressure difference of the water vapor is smaller than a predetermined pressure difference, drying becomes difficult, and deformation due to swelling of the medium M is more likely to occur, requiring the application of a higher temperature and stronger tension. Therefore, the control unit 3 drives the heating drive unit to raise the heating temperature of the first heating unit 81 to a temperature set from the water vapor pressure difference table, thereby raising it above the first heating temperature. In addition, the control unit 3 drives the winding motor to control the winding force of the winding unit 60 so that the tension is set from the water vapor pressure difference table, thereby increasing the tension of the guide unit 50 above the first tension. As a result, by applying appropriate heating and appropriate tension to the printed medium M, the medium M that has swollen due to the ejected ink can be straightened to a flat state. Therefore, cockling is suppressed, and winding is possible while suppressing sagging, etc.

[0076] According to this embodiment, the following effects can be obtained.

[0077] The printing apparatus 1 of this embodiment comprises a feeding unit 20, a transport roller 25, a printing unit 40, a guide unit 50, a winding unit 60, and a control unit 3. The guide unit 50 has a first heating unit 81 which serves as a heating unit 80 that heats the surface in contact with the medium M (the outer surface of the cylindrical unit 51), and applies tension to the printed medium M while heating it with the first heating unit 81. The control unit 3 adjusts the tension applied to the medium M by the guide unit 50 by controlling the winding force of the winding unit 60. The control unit 3 controls the winding force of the winding unit 60 and the heating temperature of the first heating unit 81 to change according to the receiving layer corresponding to the type of medium M, the amount of ink discharged corresponding to the printing conditions during printing, or the pressure difference of water vapor corresponding to the environmental conditions. This configuration allows the heating temperature of the guide section 50 (first heating section 81) and the tension of the guide section 50 (winding force of the winding section 60) to be controlled according to the type of media M, printing conditions during printing, or environmental conditions. By applying pressure to the ink-coated media M and heating it, excessive heating or pressurization, or insufficient heating or pressurization, can be prevented, and appropriate heating and pressurization can be achieved, allowing the media M, which has swollen due to the ejected ink, to be straightened to a flat surface. Consequently, cockling can be suppressed in the printed media M, and slack during winding can be suppressed, allowing the media M to be wound properly.

[0078] In the printing apparatus 1 of this embodiment, the guide portion 50 is in contact with the surface of the printed medium M opposite to the printed surface. This configuration prevents damage to the printed surface of the medium M even when the medium M is slid along the outer surface of the guide portion 50.

[0079] The printing apparatus 1 of this embodiment has a pressure roller 70 that contacts the outer circumferential surface of the medium M wound on the winding section 60 and presses it while being driven by the rotation of the winding section 60. The pressure roller 70 is equipped with a second heating section 82 that heats the outer circumferential surface of the medium M. Furthermore, the pressure roller 70 presses the medium M while heating it from the side opposite to the side heated by the guide section 50 on the medium M wound on the winding section 60. With this configuration, the second heating section 82 is provided on the pressing roller 70, and while following the rotation of the winding section 60, the printed medium M is heated and pressurized, further suppressing cockling and preventing slack during winding, thus enabling proper winding of the medium M.

[0080] The printing apparatus 1 of this embodiment includes a support surface 331 of a second support section 33 that supports the printed medium M between the printing section 40 and the guide section 50, and a third heating section 83 that heats the medium M supported on the support surface 331. This configuration, with the inclusion of the third heating section 83, further prevents excessive heating or pressurization, as well as insufficient heating or pressurization. Consequently, cockling can be suppressed on the printed medium M, and the medium M can be properly wound.

[0081] In the printing apparatus 1 of this embodiment, the control unit 3 sets the heating temperature of the first heating unit 81 to the first heating temperature and the tension applied by the guide unit 50 to the first tension when the receiving layer of the medium M has a predetermined receiving capacity. If the receiving layer of the medium M is larger than the predetermined receiving capacity, the control unit 3 sets the heating temperature of the first heating unit 81 to be lower than the first heating temperature and the tension to be weaker than the first tension. If the receiving layer of the medium M is smaller than the predetermined receiving capacity, the control unit 3 sets the heating temperature of the first heating unit 81 to be higher than the first heating temperature and the tension to be stronger than the first tension. This configuration allows for more appropriate heating and pressurization by controlling the heating temperature of the guide section 50 (first heating section 81) and the tension of the guide section 50, based on the size of the ink absorption capacity in the receiving layer of the medium M corresponding to the type of medium M. Therefore, cockling can be suppressed in the printed medium M, and slack during winding can be suppressed, allowing the medium M to be wound properly.

[0082] In the printing apparatus 1 of this embodiment, the control unit 3 sets the heating temperature of the first heating unit 81 to the first heating temperature and the tension applied by the guide unit 50 to the first tension when the amount of ink discharged by the printing unit 40 onto the medium M is a predetermined discharge amount. If the amount of ink discharged is less than the predetermined discharge amount, the control unit 3 sets the heating temperature of the first heating unit 81 to be lower than the first heating temperature and the tension to be weaker than the first tension. If the amount of ink discharged is more than the predetermined discharge amount, the control unit 3 sets the heating temperature of the first heating unit 81 to be higher than the first heating temperature and the tension to be stronger than the first tension. This configuration allows for more appropriate heating and pressurization by controlling the heating temperature of the guide section 50 (first heating section 81) and the tension of the guide section 50 based on the amount of ink discharged by the printing section 40 to adhere to the medium M, corresponding to the printing conditions during printing. Consequently, cockling is suppressed in the printed medium M, and slack during winding is also suppressed, allowing the medium M to be wound properly.

[0083] The printing apparatus 1 of this embodiment includes a temperature measuring unit 12 for measuring the temperature of the outside air and a humidity measuring unit 13 for measuring the humidity (relative humidity) of the outside air. The control unit 3 calculates the pressure difference of water vapor between the surface of the ink-coated medium M and the convection layer facing the surface, based on the measured outside air temperature and relative humidity. The control unit 3 sets the heating temperature of the first heating unit 81 to the first heating temperature and the tension applied by the guide unit 50 to the first tension when the water vapor pressure difference is a predetermined pressure difference. The control unit 3 lowers the heating temperature of the first heating unit 81 to the first heating temperature and weakens the tension to the first tension when the water vapor pressure difference is less than a predetermined pressure difference. The control unit 3 raises the heating temperature of the first heating unit 81 to the first heating temperature and strengthens the tension to the first tension. This configuration allows for unified control of temperature and humidity by calculating the pressure difference of water vapor based on the temperature and humidity corresponding to the environmental conditions, and controlling the heating temperature of the guide section 50 (first heating section 81) and the tension of the guide section 50. Compared to controlling temperature and humidity individually, this allows for more appropriate control of the heating temperature and tension, and enables the flattening of the media M swollen by the ejected ink. Consequently, cockling is suppressed in the printed media M, and slack during winding is also suppressed, allowing the media M to be wound properly.

[0084] The control method for the printing apparatus 1 of this embodiment is a control method for a printing apparatus comprising a feeding unit 20, a transport roller 25, a printing unit 40, a guide unit 50, and a winding unit 60. The guide unit 50 has a first heating unit 81 that heats the surface in contact with the medium M (the outer surface of the cylindrical unit 51), and applies tension to the printed medium M while heating it with the first heating unit 81. The tension applied to the medium M by the guide unit 50 is adjusted by controlling the winding force of the winding unit 60. The winding force of the winding unit 60 and the heating temperature of the first heating unit 81 are controlled to change according to the receiving layer corresponding to the type of medium M, the amount of ink discharged corresponding to the printing conditions during printing, or the pressure difference of water vapor corresponding to the environmental conditions. This method allows the heating temperature of the guide section 50 (first heating section 81) and the tension of the guide section 50 (winding force of the winding section 60) to be controlled according to the type of media M, printing conditions during printing, or environmental conditions. By applying pressure to the ink-coated media M and heating it, excessive heating or pressurization, or insufficient heating or pressurization, can be prevented, and appropriate heating and pressurization can be achieved. Consequently, cockling can be suppressed in the printed media M, and slack during winding can be suppressed, allowing the media M to be wound properly.

[0085] 2. Variation 1 In this embodiment, the heating temperature of the first heating section 81 in the guide section 50 and the tension in the guide section 50 (cylindrical section 51) (winding force of the winding section 60) are adjusted by the receiving capacity of the receiving layer of the medium M. However, the embodiment is not limited to this, and the heating temperature of the second heating section 82 in the pressing roller 70 and the pressing force in the pressing roller 70 (roller section 71) may also be adjusted by the receiving capacity of the receiving layer of the medium M.

[0086] The following describes an example of controlling and adjusting the heating temperature of the second heating section 82 and the pressing force of the pressing roller 70 based on the receiving capacity of the receiving layer of the medium M.

[0087] The control unit 3 sets the heating temperature of the second heating unit 82 to the second heating temperature and the pressing force applied by the pressing roller 70 to the first pressing force when the receiving layer of the medium M has a predetermined receiving capacity. If the receiving layer of the medium M is larger than the predetermined receiving capacity, the control unit 3 lowers the heating temperature to the second heating temperature and weakens the pressing force to the first pressing force. If the receiving layer of the medium M is smaller than the predetermined receiving capacity, the control unit 3 raises the heating temperature to the second heating temperature and strengthens the pressing force to the first pressing force.

[0088] Furthermore, the memory unit 7 may store a table for the receiving layer that shows the relationship between the receiving layer and the heating temperature / pressure for the pressing roller 70. The specific control method can be similarly performed by replacing the first heating unit 81 and the first heating temperature with the second heating unit 82 and the second heating temperature, and replacing the guide unit 50, tension, and first tension with the pressing roller 70, pressing force, and first pressing force, as shown in the flowchart in Figure 3. The pressing force is adjusted by driving the pressing mechanism. As a result, similar to the embodiment, appropriate heating and pressurization can be achieved by controlling the heating temperature of the pressing roller 70 (second heating section 82) and the pressing force of the pressing roller 70 in accordance with the size of the ink absorption capacity in the receiving layer of the medium M corresponding to the type of medium M. Therefore, cockling can be suppressed, and slack during winding can be suppressed, allowing the medium M to be wound properly.

[0089] 3. Variation 2 In this embodiment, the heating temperature of the first heating element 81 in the guide section 50 and the tension in the guide section 50 (cylindrical section 51) (winding force of the winding section 60) are adjusted based on the amount of ink discharged by the printing section 40 onto the medium M. However, the invention is not limited to this, and the heating temperature of the second heating element 82 in the pressing roller 70 and the pressing force in the pressing roller 70 (roller section 71) may also be adjusted based on the amount of ink discharged by the printing section 40 onto the medium M.

[0090] The following describes an example of how the heating temperature of the second heating unit 82 in the pressing roller 70 and the pressing force of the pressing roller 70 are controlled and adjusted based on the amount of ink discharged by the printing unit 40 onto the medium M.

[0091] The control unit 3 sets the heating temperature of the second heating unit 82 to the second heating temperature and the pressing force applied by the pressing roller 70 to the first pressing force when the amount of ink discharged by the printing unit 40 onto the medium M is a predetermined discharge amount. If the amount of ink discharged is less than the discharge amount, the control unit 3 lowers the heating temperature to the second heating temperature and weakens the pressing force to the first pressing force. If the amount of ink discharged is more than the predetermined discharge amount, the control unit 3 raises the heating temperature to the second heating temperature and strengthens the pressing force to the first pressing force.

[0092] Furthermore, the memory unit 7 may store a discharge amount table for the press roller 70 that shows the relationship between the ink discharge amount and the heating temperature / pressure. The specific control method can be similarly performed by replacing the first heating unit 81 and the first heating temperature with the second heating unit 82 and the second heating temperature, and replacing the guide unit 50, tension, and first tension with the press roller 70, pressing force, and first pressing force. The pressing force is adjusted by driving the pressing mechanism. As a result, similar to the embodiment, the heating temperature of the pressing roller 70 (second heating unit 82) and the pressing force of the pressing roller 70 are controlled by the amount of ink discharged by the printing unit 40 to adhere to the medium M, corresponding to the printing conditions during printing, thereby enabling appropriate heating and pressurization. Consequently, cockling is suppressed, as is slack during winding, and the medium M can be wound properly.

[0093] 4. Variation 3 In this embodiment, the heating temperature of the first heating section 81 in the guide section 50 and the tension in the guide section 50 (cylindrical section 51) (winding force of the winding section 60) are adjusted by the pressure difference of water vapor between the surface of the ink-coated medium M and the convection layer facing the surface. However, the invention is not limited to this, and the heating temperature of the second heating section 82 in the pressing roller 70 and the pressing force in the pressing roller 70 (roller section 71) may also be adjusted by the pressure difference of water vapor.

[0094] The following describes an example of controlling and adjusting the heating temperature of the second heating section 82 and the pressing force of the pressing roller 70 by the pressure difference of water vapor between the surface of the ink-coated medium M and the convection layer facing the surface.

[0095] The printing apparatus 1 includes a temperature measuring unit 12 for measuring the temperature of the outside air and a humidity measuring unit 13 for measuring the humidity of the outside air. The control unit 3 calculates the pressure difference of water vapor between the surface of the ink-coated medium M and the convection layer facing the surface, based on the measured temperature and humidity of the outside air. The control unit 3 also sets the heating temperature of the second heating unit 82 to the second heating temperature and the pressing force applied by the pressing roller 70 to the first pressing force if the water vapor pressure difference is a predetermined pressure difference. The control unit 3 then sets the heating temperature of the second heating unit 82 to the second heating temperature and the pressing force to the first pressing force if the water vapor pressure difference is greater than the predetermined pressure difference. The control unit 3 also sets the heating temperature of the second heating unit 82 to the second heating temperature and the pressing force to the first pressing force if the water vapor pressure difference is less than the predetermined pressure difference.

[0096] Furthermore, the memory unit 7 may store a water vapor pressure difference table for the pressing roller 70, which shows the correspondence between the water vapor pressure difference and the heating temperature / pressure. The specific control method can be similarly performed by replacing the first heating unit 81 and the first heating temperature with the second heating unit 82 and the second heating temperature, and replacing the guide unit 50, tension, and first tension with the pressing roller 70, pressing force, and first pressing force. The pressing force is adjusted by driving the pressing mechanism. As a result, similar to the embodiment, the pressure difference of water vapor is calculated based on the temperature and humidity corresponding to the environmental conditions, and the heating temperature of the pressing roller 70 (second heating section 82) and the pressing force of the pressing roller 70 are controlled accordingly. This allows for unified management of temperature and humidity, and compared to controlling temperature and humidity individually, the heating temperature and pressing force can be controlled more appropriately. Consequently, cockling can be suppressed, as well as slack during winding, and the medium M can be wound properly.

[0097] 5. Modification 4 In the embodiment, the heating temperature of the first heating section 81 in the guide section 50 and the tension in the guide section 50 (cylindrical section 51) are adjusted based on the receiving capacity of the receiving layer of the medium M, the amount of ink discharged by the printing section 40 to adhere to the medium M, or the pressure difference of the water vapor. In modified examples 1, 2, and 3, similar to the embodiment, the heating temperature of the second heating section 82 in the pressing roller 70 and the pressing force in the pressing roller 70 (roller section 71) are adjusted based on the receiving capacity of the receiving layer of the medium M, the amount of ink discharged by the printing section 40 to adhere to the medium M, or the pressure difference of the water vapor. However, in addition to individually controlling the heating temperature and tension of the guide section 50 and the heating temperature and pressing force of the pressing roller 70 based on the above conditions, it is also acceptable to control the heating temperature, tension, and pressing force of the guide section 50 and the pressing roller 70 so as to achieve a high level of balance between the various conditions within a predetermined heating temperature range, predetermined tension range, and predetermined pressing force range, respectively. This suppresses cockling and allows the medium M to be wound properly and reliably.

[0098] 6. Variation 5 In this embodiment, the heating temperature of the first heating section 81 in the guide section 50 and the tension of the guide section 50 (winding force of the winding section 60) are changed according to the receiving capacity of the receiving layer of the medium M corresponding to the type of medium M, the amount of ink discharged by the printing section 40 to adhere to the medium M corresponding to the printing conditions during printing, or the pressure difference of water vapor corresponding to the environmental conditions. However, the control unit 3 is not limited to this, and may also control the heating temperature of the first heating section 81 in the guide section 50 and the tension of the guide section 50 (winding force of the winding section 60) according to the type of medium M, printing conditions, and environmental conditions other than the receiving capacity of the receiving layer, the amount of ink discharged, and the pressure difference of water vapor. The same applies to the pressing roller 70.

[0099] 7. Variation 6 In this embodiment, the first heating unit 81 is installed inside the cylindrical portion 51 of the guide portion 50. However, it is not limited to this, and the first heating unit 81 may also be installed on the outer surface of the cylindrical portion 51 opposite to the outer surface in which the medium M contacts and slides. This allows the first heating unit 81 to apply heat to the medium M by transferring heat to the cylindrical portion 51 from the outer surface side.

[0100] 8. Variation 7 In this embodiment, the third heating unit 83 is installed between the printing unit 40 and the guide unit 50, facing the second support unit 33 that supports the printed medium M. The third heating unit 83 faces the medium M, which is supported and transported by the support surface 331 of the second support unit 33, and heats the medium M from the printed side. However, it is not limited to this, and the third heating unit 83 may be installed on the side of the second support unit 33 opposite to the support surface 331. In this case, the third heating unit 83 may be composed of, for example, a sheet heater. The sheet heater is constructed by sandwiching a heating element such as metal foil inside a sheet member such as a flexible synthetic resin, and generates heat so that the temperature distribution is substantially uniform. As a result, the third heating unit 83 can apply heat to the medium M by transferring heat to the second support unit 33 from the side of the second support unit 33 opposite to the support surface 331.

[0101] 9. Variation 8 In this embodiment, the pressing roller 70 is equipped with a pressing mechanism for pressing the roller portion 71 against the roll body R2. However, it is not limited to this, and the pressing mechanism may not be used, and the roll body R2 may be pressed by the weight of the roller portion 71 of the pressing roller 70. In this case, the pressing force of the pressing roller 70 will be approximately constant.

[0102] 10. Variation 9 In this embodiment, the first heating temperature of the first heating section 81 in the guide section 50 and the first tension of the guide section 50 (winding force of the winding section 60) are set according to the type of medium M, the printing conditions during printing, or the environmental conditions. This first heating temperature may be the same value or different values ​​under each condition. Similarly, the first tension may be the same value or different values ​​under each condition. [Explanation of Symbols]

[0103] 1...Printing device, 3...Control unit, 12...Temperature measuring unit, 13...Humidity measuring unit, 20...Feeding unit, 21...Core tube, 22...Holder, 25...Conveyor roller, 26...Driven roller, 27...Driven roller, 30...Support unit, 31...First support unit, 32...Platen, 33...Second support unit, 40...Printing unit, 41...Discharge head, 42...Carriage, 50...Guide unit, 51...Cylindrical unit, 60...Winding unit, 61...Core tube, 62...Holder, 70...Pressing roller, 71...Roller unit, 80...Heating unit, 81...First heating unit, 82...Second heating unit, 83...Third heating unit, 331...Support surface, R1...Roll body, R2...Roll body, M...Media, F...Conveying direction.

Claims

1. A feeding unit that feeds out the printed material wound in a roll, A conveying roller that conveys the printing medium dispensed from the dispensing unit in the conveying direction, A printing unit that applies liquid to the transported printing medium and performs printing, A guide portion that contacts the printing medium and applies tension, A winding unit for winding up the printed medium after printing, A temperature measuring unit that measures the temperature of the outside air, The humidity measuring unit for measuring the humidity of the outside air, It comprises a control unit and, The feeding unit, the transport roller, the printing unit, the guide unit, and the winding unit are arranged in this order from the upstream side in the transport direction. The aforementioned guide section is It has a first heating unit that heats the guide surface which is the surface in contact with the printing medium, and applies the tension to the printed medium after printing while heating it with the first heating unit via the guide surface, The control unit, The tension applied by the guide section to the printing medium is adjusted by controlling the winding force of the winding section, and The winding force of the winding section and the heating temperature of the first heating section are controlled to vary according to the type of printing medium, printing conditions during printing, or environmental conditions. Based on the measured temperature and humidity of the outside air, the pressure difference of water vapor between one surface of the printing medium to which the liquid is attached and the convection layer facing that surface is calculated. When the pressure difference of the water vapor is a predetermined pressure difference, the heating temperature of the first heating section is set to the first heating temperature, and the tension applied by the guide section is set to the first tension. If the pressure difference of the water vapor is greater than the predetermined pressure difference, the heating temperature is lowered to a lower temperature than the first heating temperature, and the tension is reduced to a lower tension than the first tension. A printing apparatus characterized in that, when the pressure difference of the water vapor is smaller than the predetermined pressure difference, the heating temperature is raised higher than the first heating temperature and the tension is increased higher than the first tension.

2. A feeding unit that feeds out the printed material wound in a roll, A conveying roller that conveys the printing medium dispensed from the dispensing unit in the conveying direction, A printing unit that applies liquid to the transported printing medium and performs printing, A guide portion that contacts the printing medium and applies tension, A winding unit for winding up the printed medium after printing, It comprises a control unit and, The feeding unit, the transport roller, the printing unit, the guide unit, and the winding unit are arranged in this order from the upstream side in the transport direction. The aforementioned guide section is It has a first heating unit that heats the guide surface which is the surface in contact with the printing medium, and applies the tension to the printed medium after printing while heating it with the first heating unit via the guide surface, The control unit, The tension applied by the guide section to the printing medium is adjusted by controlling the winding force of the winding section, and The winding force of the winding section and the heating temperature of the first heating section are controlled to vary according to the type of printing medium, printing conditions during printing, or environmental conditions. The control unit, when the receiving layer of the printing medium has a predetermined receiving capacity, sets the heating temperature of the first heating unit as the first heating temperature and the tension applied by the guide unit as the first tension. If the receiving layer of the printing medium is larger than the predetermined receiving capacity, the heating temperature is lower than the first heating temperature, and the tension is weaker than the first tension. A printing apparatus characterized in that, if the receiving layer of the printing medium is smaller than the predetermined receiving capacity, the heating temperature is set higher than the first heating temperature and the tension is set higher than the first tension.

3. A printing apparatus according to claim 1 or claim 2, The printing apparatus is characterized in that the guide surface is in contact with the side of the printing medium after printing that is opposite to the side on which printing has been done.

4. A printing apparatus according to any one of claims 1 to 3, The winding section has a pressing roller that presses against the outer surface of the printing medium wound up on it, The pressing roller is equipped with a second heating section that heats the outer surface, The printing apparatus is characterized in that the pressing roller presses the printing medium, which is wound onto the winding section, from one side of the printing medium while heating it.

5. A printing apparatus according to any one of claims 1 to 4, A printing apparatus characterized by comprising, between the printing section and the guide section, a support surface for supporting the printed medium after printing, and a third heating section for heating the printed medium supported on the support surface.

6. A feeding unit that feeds out the printed material wound in a roll, A conveying roller that conveys the printing medium dispensed from the dispensing unit in the conveying direction, A printing unit that applies liquid to the transported printing medium and performs printing, A guide portion that contacts the printing medium and applies tension, A winding unit for winding up the printed medium after printing, A temperature measuring unit that measures the temperature of the outside air, A control method for a printing apparatus comprising a humidity measuring unit for measuring the humidity of the outside air, The feeding unit, the transport roller, the printing unit, the guide unit, and the winding unit are arranged in this order from the upstream side in the transport direction. The guide section has a heating section that heats the guide surface, which is the surface in contact with the printing medium, and applies tension to the printed medium after printing while heating it with the heating section via the guide surface. The aforementioned printing apparatus, The tension applied by the guide section to the printing medium is adjusted by controlling the winding force of the winding section, and The winding force of the winding section and the heating temperature of the heating section are controlled to vary according to the type of printing medium, printing conditions during printing, or environmental conditions. Based on the measured temperature and humidity of the outside air, the pressure difference of water vapor between one surface of the printing medium to which the liquid is attached and the convection layer facing that surface is calculated. When the pressure difference of the steam is a predetermined pressure difference, the heating temperature of the heating section is set to the first heating temperature, and the tension applied by the guide section is set to the first tension. If the pressure difference of the water vapor is greater than the predetermined pressure difference, the heating temperature is lowered to a lower temperature than the first heating temperature, and the tension is reduced to a lower tension than the first tension. A method for controlling a printing apparatus, characterized in that, if the pressure difference of the water vapor is smaller than the predetermined pressure difference, the heating temperature is set higher than the first heating temperature and the tension is set higher than the first tension.

7. A feeding unit that feeds out the printed material wound in a roll, A conveying roller that conveys the printing medium dispensed from the dispensing unit in the conveying direction, A printing unit that applies liquid to the transported printing medium and performs printing, A guide portion that contacts the printing medium and applies tension, A control method for a printing apparatus comprising a winding unit for winding up the printing medium after printing, The feeding unit, the transport roller, the printing unit, the guide unit, and the winding unit are arranged in this order from the upstream side in the transport direction. The guide section has a heating section that heats the guide surface, which is the surface in contact with the printing medium, and applies tension to the printed medium after printing while heating it with the heating section via the guide surface. The aforementioned printing apparatus, The tension applied by the guide section to the printing medium is adjusted by controlling the winding force of the winding section, and The winding force of the winding section and the heating temperature of the heating section are controlled to vary according to the type of printing medium, printing conditions during printing, or environmental conditions. When the receiving layer of the printing medium has a predetermined receiving capacity, the heating temperature of the heating section is set as the first heating temperature, and the tension applied by the guide section is set as the first tension. If the receiving layer of the printing medium is larger than the predetermined receiving capacity, the heating temperature is lower than the first heating temperature, and the tension is weaker than the first tension. A method for controlling a printing apparatus, characterized in that, if the receiving layer of the printing medium is smaller than the predetermined receiving capacity, the heating temperature is set higher than the first heating temperature and the tension is set higher than the first tension.

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