Printing apparatus and

Abstract

When the heating means is turned off, the temperature of the supporting member is excessively lowered. As a result, when printing is performed again, it may be necessary to wait until the temperature of the support member rises.SOLUTION: A printing apparatus includes a printing unit 6 that performs printing on a medium M by applying a liquid, a medium support unit 7 that supports the medium to which the liquid is applied, a heating unit 8 that heats the medium supported by the medium support unit, a temperature detection unit 9 that detects a temperature of the medium or the medium support unit, and a control unit 12 that performs feedback control of the heating unit such that a detected temperature detected by the temperature detection unit becomes a set temperature, in which the control unit sets a set temperature after printing is finished to be lower than a set temperature during printing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to printing devices. [Background technology]

[0002] A conventional printing device has been disclosed that includes a liquid applying means for applying a liquid and a drying device for drying the conveyed member to which the liquid has been applied, as shown in Patent Document 1. In the printing device described in Patent Document 1, the heating means is turned off when the temperature of the support member that supports the conveyed member reaches or exceeds a predetermined temperature. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2018-12323 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the printing device described in Patent Document 1, turning off the heating means causes the temperature of the support member to drop too much, which can lead to the need to wait until the temperature of the support member rises before printing again. [Means for solving the problem]

[0005] The printing device comprises a printing unit that applies liquid to print on a medium, a medium support unit that supports the medium to which the liquid has been applied, a heating unit that heats the medium supported by the medium support unit, a temperature detection unit that detects the temperature of the medium or the medium support unit, and a control unit that feedback controls the heating unit so that the detected temperature detected by the temperature detection unit becomes a set temperature, and the control unit sets the set temperature after printing is completed to be lower than the set temperature during printing. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic cross-sectional view showing the configuration of a printing apparatus. [Figure 2] FIG. 1 is a block diagram illustrating the configuration of a printing apparatus. [Figure 3] FIG. 2 is a schematic diagram showing the configuration of the main parts of the printing device as seen from above in FIG. 1. [Figure 4] 4 is a flowchart showing temperature control of the printing device. DETAILED DESCRIPTION OF THE INVENTION

[0007] The printing device 1 of this embodiment will be described below with reference to the drawings. The printing device 1 shown in Fig. 1 is, for example, an inkjet printer that prints images such as text and photographs on a medium M by applying ink, which is an example of a "liquid," to the medium M being transported.

[0008] In the drawings shown below, the scale of each component is different from the actual scale so that each component can be recognized. In each drawing, the same components are denoted by the same reference numerals, and redundant explanations are omitted. Furthermore, in each drawing, at least one of the X-axis, Y-axis, and Z-axis is illustrated as necessary as mutually orthogonal coordinate axes. The X-axis, Y-axis, and Z-axis are each marked with an arrow. For each of the X-axis, Y-axis, and Z-axis, the direction of the arrow indicates the positive direction, and the direction opposite to the arrow indicates the negative direction.

[0009] The Y axis is an axis parallel to the installation surface of the printing device 1 and corresponds to the depth direction of the printing device 1. The positive direction of the Y axis is the direction from the back to the front of the printing device 1. The X axis is an axis parallel to the installation surface of the printing device 1 and corresponds to the width direction of the printing device 1 and the width direction of the medium M. The positive direction of the X axis is the direction from right to left of the printing device 1 when viewed from the front of the printing device 1. The Z axis is an axis perpendicular to the installation surface of the printing device 1 and corresponds to the height direction of the printing device 1. The positive direction of the Z axis is the direction from bottom to top of the printing device 1.

[0010] In the printing device 1, the positive direction of the X axis is referred to as the left direction or simply left, and the negative direction is referred to as the right direction or simply right. The positive direction of the Y axis is referred to as the forward direction or simply front, and the negative direction is referred to as the rearward direction or simply rear. The positive direction of the Z axis is referred to as the upward direction or simply up, and the negative direction is referred to as the downward direction or simply down. In the printing device 1, the direction in which the medium M is transported is also referred to as downstream, and the opposite direction is also referred to as upstream.

[0011] The configuration of the printing device 1 will be described with reference to FIGS. 1 to 3. As shown in FIGS. 1 and 2, the printing device 1 includes a supply unit 2, a guide 3, a transport unit 4, a platen 5, a printing unit 6, a medium support unit 7, a heating unit 8, a temperature detection unit 9, a blower unit 10, a winding unit 11, and a control unit 12. The medium M is transported along the surfaces of the guide 3, the platen 5, and the medium support unit 7, which are surfaces that support the medium M. The direction along the surfaces of the guide 3, the platen 5, and the medium support unit 7 is the transport direction F of the medium M. The transport direction F intersects with the X-axis. The supply unit 2, the guide 3, the transport unit 4, the platen 5, the printing unit 6, the medium support unit 7, the heating unit 8, the temperature detection unit 9, the blower unit 10, and the winding unit 11 are arranged from upstream to downstream in the transport direction F.

[0012] The medium M is, for example, plain paper, synthetic paper, photo paper, or other paper, and has a long, rectangular shape. The medium M is wound as a roll R1 and set in the supply unit 2 of the printing device 1. The supply unit 2 rotates the roll R1 using a supply motor (not shown), and can feed the medium M from the roll R1 in the transport direction F. The medium M may, for example, be a single sheet of paper or a fabric made of natural or synthetic fibers.

[0013] The guide 3 guides the medium M supplied from the supply unit 2 toward the transport unit 4. The transport unit 4 includes a drive roller 4a and a driven roller 4b. The transport unit 4 drives the drive roller 4a by a transport motor (not shown), and transports the medium M toward the platen 5 while sandwiching the medium M between the drive roller 4a and the driven roller 4b. Note that the drive and driven relationship between the drive roller 4a and the driven roller 4b may be reversed.

[0014] The medium M is transported by the transport unit 4 toward the platen 5 and reaches a position between the platen 5 and the printing unit 6, which face each other. The platen 5 supports the medium M. The printing unit 6 includes an inkjet head (not shown) and a carriage (not shown). The printing unit 6 applies ink to print on the medium M. The carriage can be moved left and right by a carriage motor (not shown).

[0015] The printing device 1 can be fitted with ink cartridges or ink tanks that store ink of each of the ink colors CMYK (Cyan, Magenta, Yellow, Black), for example. The printing unit 6 is equipped with a supply mechanism (not shown) that supplies ink from the ink cartridges or the like to the head. The supply mechanism supplies ink of each color from the ink cartridges or the like to nozzles (not shown) formed in the head.

[0016] The head is mounted on a carriage and moves back and forth left and right above the medium M together with the carriage, which can move left and right. The head applies ink downward from the nozzles while moving above the medium M under control of the control unit 12 based on print data. In this way, the ink is applied to the first surface M1, which is the printing surface of the medium M. Note that the ink color can be any combination of four or more colors, including, for example, shades of CMYK. The ink also contains a solvent. For example, if the ink is eco-solvent ink, it contains a pigment and an organic solvent.

[0017] The medium M onto which ink has been applied by the printing unit 6 is transported to the medium support unit 7, which is located downstream of the platen 5 in the transport direction F. The medium support unit 7 supports the medium M onto which ink has been applied. The medium support unit 7 has a bent portion 7a formed on the upstream side. The medium support unit 7 is shaped so that it bends from the front to the front-downward direction at the bent portion 7a from upstream to downstream in the transport direction F.

[0018] The direction in which the medium M is transported is changed from a forward direction to a front-down direction by the bent portion 7a of the medium support unit 7. That is, as the medium M passes through the bent portion 7a and is transported downstream in the transport direction F, the first surface M1 of the medium M changes so that it tilts from upward to forward. Note that if the bent portion 7a is formed to be angular, a crease will be left on the medium M, so it is preferable to form the bent portion 7a so that its cross section is arc-shaped when viewed from the left or right.

[0019] The heating unit 8 is disposed over a wide area on the rear surface of the medium support unit 7, opposite the front surface, and heats the medium M supported by the medium support unit 7 via the medium support unit 7. The heating unit 8 can be, for example, a heat source lamp, a heater tube, a tube heater, or a rubber heater. In this embodiment, the heating unit 8 is composed of an electric heating wire heater 8a, and a tube heater that is a single long member is used.

[0020] The ink applied to the medium M is heated by the heating unit 8 from the second surface M2, which is the transport surface of the medium M. At this time, the solvent contained in the ink turns into gas from the first surface M1 and escapes from the medium M. In the following explanation, the process of the solvent turning into gas is referred to as evaporation, and in the case of organic solvents, this is specifically referred to as volatilization. For example, in the case of medium M printed with eco-solvent ink, the medium M is heated from the second surface M2 by the heating unit 8, the organic solvent volatilizes from the first surface M1, and the pigment remains on the medium M.

[0021] As will be described later, a predetermined tension is applied to the medium M transported by the transport unit 4 by being wound up by the winding unit 11. With the predetermined tension applied to the medium M, the medium M is bent at the bending portion 7a of the medium support unit 7, thereby preventing the second surface M2 from lifting up from the surface of the medium support unit 7. Because the second surface M2 of the medium M contacts the surface of the medium support unit 7, heat is easily transferred to the medium M, and evaporation of the solvent from the first surface M1 is promoted.

[0022] In order to prevent the second surface M2 from lifting up from the surface of the medium support unit 7, it is preferable that the conveying direction F of the medium M at the downstream end of the medium support unit 7 be changed further downward than the conveying direction F that has been changed to a downward-front direction by the bent portion 7a. Furthermore, since forming the downstream end of the medium support unit 7 angularly would leave a crease in the medium M, it is preferable that the cross section be formed to be arc-shaped when viewed from the left or right.

[0023] The temperature detection unit 9 is disposed on the rear surface of the medium support unit 7 and detects the temperature of the medium support unit 7. The temperature detection unit 9 includes a first temperature detection unit 9a and a second temperature detection unit 9b. The first temperature detection unit 9a and the second temperature detection unit 9b can be, for example, a resistance temperature detector, a linear resistor, or a thermistor. In this embodiment, the first temperature detection unit 9a and the second temperature detection unit 9b are thermistors, which are temperature detection elements. The first temperature detection unit 9a is disposed near the downstream heating unit 8 of the heating units 8 disposed over a wide area on the rear surface of the medium support unit 7, and can detect the temperature near the downstream heating unit 8. The second temperature detection unit 9b is disposed near the upstream heating unit 8 of the heating units 8 disposed over a wide area on the rear surface of the medium support unit 7, and can detect the temperature near the upstream heating unit 8.

[0024] Although the temperature detection unit 9 has been described as being positioned on the back surface of the medium support unit 7 and detecting the temperature of the medium support unit 7, for example, the temperature detection unit 9 may be built in near the surface of the medium support unit 7 and detect the surface temperature of the medium support unit 7, or may detect the temperature of the medium M.

[0025] The air blowing unit 10 is disposed opposite the medium support unit 7 and blows air toward the medium support unit 7. The air blowing unit 10 is disposed opposite the electric heating wire heater 8a of the heating unit 8, which is disposed upstream in the conveyance direction F, across the medium support unit 7. The air blowing unit 10 includes a fan 10a. The air blowing unit 10 can blow air toward the first surface M1 of the medium M that is supported and heated by the medium support unit 7. The winding unit 11 winds up the medium M that has been dried by the heating unit 8 and the air blowing unit 10 into a winding roll R2. The winding unit 11 includes a winding motor (not shown) and is capable of rotating the winding roll R2.

[0026] The control unit 12 includes a CPU (Central Processing Unit) that controls all the components of the printing device 1, a UART (Universal Asynchronous Receiver Transmitter) that manages input and output, and logic circuits such as an FPGA (Field Programmable Gate Array) and a PLD (Programmable Logic Device). The CPU is also called a processor. The control unit 12 includes a storage unit 12a. The storage unit 12a includes rewritable nonvolatile memory such as a flash ROM (Read Only Memory) and an HDD (Hard Disk Drive), and volatile memory such as RAM (Random Access Memory). The CPU of the control unit 12 reads programs such as firmware stored in the nonvolatile memory of the storage unit 12a and executes various programs using the volatile memory of the storage unit 12a as a working area.

[0027] As shown in FIG. 2, the supply unit 2, the conveying unit 4, the printing unit 6, the heating unit 8, the temperature detecting unit 9, the blowing unit 10, and the winding unit 11 are controlled by the control unit 12 executing various programs.

[0028] The control unit 12 further includes an A / D converter (Analog-to-digital converter), not shown, and is able to calculate the temperature based on the resistance value of the temperature detection unit 9, which changes in response to temperature changes. A temperature table corresponding to the resistance value of the temperature detection unit 9 is stored in the memory unit 12a. The control unit 12 can refer to the memory unit 12a to obtain the temperature corresponding to the resistance value of the temperature detection unit 9. In this way, the control unit 12 can know the temperature of the medium support unit 7 detected by the temperature detection unit 9.

[0029] The control unit 12 determines the temperature of the medium support unit 7 detected by the temperature detection unit 9 and can adjust the temperature of the heating unit 8. The control unit 12 can adjust the temperature of the heating unit 8, for example, by controlling the power supplied to the heating unit 8 using a transistor or the like. In the following explanation, the temperature adjustment of the heating unit 8 by the control unit 12 is referred to as temperature control. The control unit 12 performs so-called temperature feedback control, which controls the power applied to the heating unit 8 so that the temperature of the medium support unit 7 detected by the temperature detection unit 9 becomes a predetermined value.

[0030] The control unit 12 can control the temperature of the heating unit 8 based on the temperature detected by the first temperature detection unit 9a. The control unit 12 can also control the temperature of the heating unit 8 based on the temperature detected by the second temperature detection unit 9b. In this way, the control unit 12 can individually control the temperature of the heating unit 8 based on the temperatures detected by the first temperature detection unit 9a and the second temperature detection unit 9b.

[0031] 3, the medium M is transported from upstream to downstream in the transport direction F between the opposing platen 5 and printing unit 6. The printing unit 6 applies ink to a first surface M1, which is the printing surface of the medium M, while moving back and forth in the left-right direction above the medium M, to perform printing. The medium M printed by the printing unit 6 is then transported from upstream to downstream in the transport direction F between the opposing medium support unit 7 and air blower unit 10, which are located downstream of the platen 5.

[0032] The first temperature detection unit 9a of the temperature detection unit 9 is arranged on the right side, in the -X direction, on the back surface of the medium support unit 7. It is also arranged near the electric heating wire heater 8a, which is arranged on the downstream side, of the heating units 8 arranged on the back surface of the medium support unit 7. The second temperature detection unit 9b is arranged on the left side, in the +X direction, on the back surface of the medium support unit 7. It is also arranged near the electric heating wire heater 8a, which is arranged on the upstream side, of the heating units 8 arranged on the back surface of the medium support unit 7.

[0033] In the printing device 1 of this embodiment, ink can be applied to the medium M even when the medium M is transported with a width of different sizes, such as 10 inches or 64 inches. The medium M is supported with its right edge in the width direction aligned with the right side of the medium support unit 7. In the area of ​​the surface of the medium support unit 7 where the medium M is supported, heat from the medium support unit 7 heated by the heating unit 8 is absorbed by the medium M. In the following description, the area of ​​the medium support unit 7 where the medium M is supported is referred to as the "support area." In this embodiment, the first temperature detection unit 9a is located on the right side of the medium support unit 7, so that the temperature of the support area can be detected even when media M of different sizes are transported.

[0034] Furthermore, in areas of the surface of the medium support unit 7 where the medium M is not supported, the heat of the medium support unit 7 heated by the heating unit 8 is not taken away by the medium M. In the following description, the areas of the medium support unit 7 where the medium M is not supported are referred to as the "non-support area." In this embodiment, the second temperature detection unit 9b is located on the left side of the medium support unit 7, so that it can detect the temperature of the non-support area even when media M of different sizes are transported. Note that when a medium M of a width that covers the entire width of the medium support unit 7 is transported, there is no non-support area. In this case, the second temperature detection unit 9b detects the temperature of the medium support unit 7 where heat is taken away by the medium M.

[0035] The air blowing unit 10 is disposed in a position facing the electric heating wire heater 8a, which is disposed on the upstream side of the heating unit 8 in the conveying direction F, across the medium support unit 7. The medium M conveyed to the medium support unit 7 faces the air blowing unit 10. The air blowing unit 10 includes multiple fans 10a disposed in the width direction of the medium support unit 7. In this embodiment, three fans 10a of the air blowing unit 10 are arranged side by side in the left-right direction, which is the width direction of the medium M.

[0036] The number of fans 10a in the blower unit 10 can be any number. The control unit 12 can also individually control the multiple fans 10a. For example, it is possible to operate only the fan 10a at a desired position, or to change the airflow of the fan 10a selected according to the width direction size of the medium M being transported. In this way, the medium M transported to the medium support unit 7 is dried by being heated via the medium support unit 7. Furthermore, the drying of the medium M is promoted by being exposed to the air blown from the blower unit 10.

[0037] As described above, heat is absorbed from the support region of the medium support unit 7 by the medium M. For this reason, the control unit 12 performs feedback control on the heating unit 8 so that the first detected temperature detected by the first temperature detection unit 9a of the temperature detection unit 9 becomes a predetermined set temperature. As feedback control, for example, a proportional integral differential controller (PID) control can be applied. Note that after a certain period of printing, the heating by the heating unit 8 and the heat absorbed by the medium M may approach a state of equilibrium. In this case, the first detected temperature stabilizes at a temperature lower than the set temperature, and fluctuations become small.

[0038] Furthermore, the non-support area of ​​the medium support unit 7 has a higher temperature than the support area because the medium M does not take heat from the medium support unit 7. For this reason, the control unit 12 controls the temperature so that the temperature of the non-support area does not become excessively high. Specifically, when the second detected temperature detected by the second temperature detection unit 9b rises and reaches the upper limit set temperature, the control unit 12 suppresses the output of the heating unit 8. The output of the heating unit 8 is limited to, for example, 10%. This limit controls the temperature of the medium support unit 7 so that it does not exceed the upper limit set temperature, ensuring the safety of the printing device 1. The upper limit set temperature is, for example, 62°C.

[0039] Furthermore, if the blower unit 10 is not operating due to a malfunction or other reason, the temperature of the non-support area of ​​the medium support unit 7 will be higher than that of the support area because the heat of the medium support unit 7 is not removed by the blower unit 10. For this reason, the control unit 12 determines whether the blower unit 10 is operating, and if it determines that the blower unit 10 is not operating, it suppresses the output of the heating unit 8. The output of the heating unit 8 is limited to, for example, 50%. This limit controls the temperature of the non-support area of ​​the medium support unit 7 so that it does not exceed a specific temperature, ensuring the safety of the printing device 1. The specific temperature is, for example, 60°C. Note that a method for determining whether the blower unit 10 is not operating can be performed by having the control unit 12 execute an operation confirmation program for the blower unit 10 in advance.

[0040] The temperature control of the printing device 1 will be described below with reference to FIG. 4. The subsequent operations are controlled by the control unit 12. In the following description, the "printing operation" includes the operation of applying ink to the medium M and transporting the portion of the medium M to which the ink has been applied to a position facing the air blower 10 under control of the control unit 12 based on print data. The term "during printing" refers to the period from the start to the end of the "printing operation." The term "end of printing" refers to the time when the "printing operation" ends during "printing." The terms "printing ends" or "end of printing" refer to the end of the "printing operation." The term "after end of printing" refers to the period after the "printing operation" ends.

[0041] 4, first, in step S1, the control unit 12 determines whether a print request has been received from an external computer (not shown) or the like. If the determination in step S1 is "NO," step S1 is repeated until a print request is received. If the determination in step S1 is "YES," the process proceeds to step S2.

[0042] In step S2, the control unit 12 sets the set temperature used for temperature control to a first target temperature stored in advance in the memory unit 12a. The first target temperature is a temperature at which the printed medium M can be dried, and is an example of a temperature that the control unit 12 aims for using PID control during printing. The first target temperature is determined in advance through experiments and is stored in the memory unit 12a. An example of the first target temperature is 50°C. Note that the first target temperature may be set by the user within the range of 35°C to 55°C, for example, depending on conditions such as the ambient temperature, the composition of the ink, and the amount of ink applied.

[0043] When volatilizing the organic solvent contained in the eco-solvent ink from the medium M, it is preferable that the control unit 12 controls the temperature of the medium support unit 7 heated by the heating unit 8 by setting the temperature in the range of 35°C to 55°C.

[0044] Next, in step S3, the control unit 12 turns on the electric heating wire heater 8a to start heating the medium support unit 7. Next, in step S4, the control unit 12 determines whether the first detected temperature detected by the first temperature detection unit 9a has reached the first target temperature set in step S2. If the determination in step S4 is "NO," step S4 is repeated until the first detected temperature reaches the first target temperature. If the determination in step S4 is "YES," the process proceeds to step S5.

[0045] In step S5, the control unit 12 turns on the fan 10a to start blowing air toward the medium support unit 7 in preparation for the start of printing in the next step S6. Note that by continuing to blow air from the fan 10a even during printing, the control unit 12 promotes drying of the medium M that has become moistened by the application of ink and cools the non-support area so that the temperature of the non-support area does not rise above a predetermined temperature. Next, in step S6, the control unit 12 starts printing on the medium M based on the print data.

[0046] Next, in step S7, the control unit 12 determines whether printing has finished. If the determination in step S7 is "NO," step S7 is repeated until printing has finished. If the determination in step S7 is "YES," the process proceeds to step S8.

[0047] In step S8, the control unit 12 sets the set temperature used for temperature control after printing to a second target temperature that is lower than the first target temperature, which is the set temperature during printing. In other words, in step S8, the control unit 12 sets the set temperature after printing to be lower than the set temperature during printing. The second target temperature is a temperature at which printing can be started without waiting for the temperature of the heating unit 8 to rise, even if the next print request is received, and is an example of a temperature that the control unit 12 aims for using PID control after printing is completed.

[0048] The control unit 12 may set the second target temperature, which is the set temperature after printing is completed, to the same temperature as the first detected temperature when fluctuations are small and stable during printing, based on the first detected temperature during printing. Alternatively, the control unit 12 may set the second target temperature, which is the set temperature after printing is completed, to the same temperature as the first detected temperature detected at the end of printing, based on the first detected temperature at the end of printing. The first detected temperatures during printing and at the end of printing are detected as temperatures lower than the first target temperature, which is the set temperature during printing. This is because, in the medium support unit 7 heated by the heating unit 8, heat is lost from the medium support unit 7 as the solvent evaporates from the first surface M1. Alternatively, this is because the temperature of the medium support unit 7 is insufficient due to the output of the heating unit 8. This allows the set temperature after printing to be set lower than the set temperature during printing.

[0049] Next, in step S9, the control unit 12 determines whether a predetermined period of time has elapsed since printing ended. In other words, it determines whether a predetermined period of time has elapsed since the determination in step S7 was "YES." If the determination in step S9 is "NO," step S9 is repeated until the predetermined period of time has elapsed since printing ended. If the determination in step S9 is "YES," the process proceeds to step S10.

[0050] In step S10, the control unit 12 turns off the operation of the fan 10a to stop blowing air toward the medium support unit 7. In this way, the control unit 12 operates the fan 10a to continue blowing air from the blower 10 not only during printing but also from the end of printing in step S7 through the predetermined period in step S9 to step S10. The predetermined period is determined in advance through experiments and is stored in the memory unit 12a. The predetermined period is, for example, 30 seconds.

[0051] As described above, in this embodiment, the set temperature after printing is completed is set lower than the set temperature during printing. Also, in this embodiment, because the heating unit 8 is PID controlled, the output of the heating unit 8 may be temporarily increased after printing is completed to compensate for the drop in temperature after printing is completed. As a result, the temperature of the non-support area of ​​the medium support unit 7 may rise, but because air flow continues for a predetermined period after printing is completed, an excessive rise in the temperature of the non-support area can be prevented.

[0052] Next, in step S11, the control unit 12 determines whether the first detected temperature detected by the first temperature detection unit 9a has become approximately the same as the second target temperature. If the determination in step S11 is "NO," step S11 is repeated until the first detected temperature becomes approximately the same as the second target temperature. If the determination in step S11 is "YES," the control unit 12 continues the second target temperature and waits for a new print request. Note that when a new print request is received, the control unit 12 proceeds to step S1 and starts printing on the medium M based on the print data.

[0053] In this way, the medium M is heated via the medium support unit 7 by temperature control by the control unit 12, and the solvent evaporates from the first surface M1. The solvent evaporated from the first surface M1 is blown away by the air blown from the air blowing unit 10. This promotes drying of the medium M.

[0054] As described above, the printing device 1 of this embodiment can provide the following effects. According to this printing device 1, the control unit 12 sets the second target temperature, which is the set temperature after printing, lower than the first target temperature, which is the set temperature during printing, to maintain the temperature of the medium support unit 7 after printing is completed, thereby preventing the temperature of the medium support unit 7 from dropping too much. This allows printing to be resumed smoothly.

[0055] According to this printing device 1, the control unit 12 sets the second target temperature, which is the set temperature after printing is completed, based on the first detected temperature during printing, so the set temperature after printing can be set to a detected temperature that reflects the actual conditions during printing. This also allows printing to be resumed smoothly.

[0056] According to this printer 1, the control unit 12 sets the second target temperature, which is the set temperature after printing is completed, based on the first detected temperature at the time of printing completion, so the set temperature after printing is set to a detected temperature that reflects the actual conditions at the time of printing completion. This also allows printing to be restarted smoothly.

[0057] According to this printing device 1, the temperature detection unit 9 detects the temperature of the medium support unit 7 at a position where the medium M is supported. This makes it possible to more accurately detect the first detection temperature required to smoothly resume printing, compared to when detecting the temperature of the medium support unit 7 at a position where the medium M is not supported.

[0058] According to this printing device 1, the control unit 12 performs PID control on the heating unit 8, and therefore is able to perform feedback control with quick response, stable control, and suppression of sudden changes.

[0059] This printing device 1 is provided with an air blower 10 that is disposed opposite the medium support unit 7 and blows air toward the medium support unit 7, and the control unit 12 continues blowing air from the air blower 10 for a predetermined period after printing is completed. This promotes drying of the medium M and prevents the temperature of the non-support area from rising excessively.

[0060] According to this printing device 1, the heating unit 8 heats the medium M via the medium support unit 7, so the medium M can be heated evenly.

[0061] Although the present embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and may be changed, substituted, deleted, etc., without departing from the spirit of the present invention. Furthermore, other embodiments as described below may also be used. Even in these cases, the same effects as those of this embodiment can be obtained.

[0062] In this embodiment, the printing unit 6 of the printing device 1 has been described as a so-called serial type in which the head is mounted on a carriage and moves, but for example, the printing unit 6 may also be a so-called line type in which there is no carriage and the head is fixed.

[0063] In this embodiment, the control unit 12 is described as controlling the temperature of a tube heater that is a single long member, but the control unit 12 may also control the temperature of tube heaters that are two or more long members.

[0064] In this embodiment, PID control is explained using predetermined temperatures as examples of the set temperature and the detected temperature, but the PID control may also be performed by PID gain tuning so that a predetermined range is set for the difference between the set temperature and the current detected temperature.

[0065] In this embodiment, the "printing operation" includes the operation of applying ink to the medium M under control by the control unit 12 based on print data and transporting the portion of the medium M to which the ink has been applied to a position facing the air blower 10. However, this is not limited to this. The "printing operation" may also be the operation of applying ink to the medium M under control by the control unit 12 based on print data. After the first detected temperature reaches the first target temperature in step S4, the medium support unit 7 is cooled in step S5 by air blown from the fan 10a, which has been turned on. Therefore, even if the medium M is not transported to a position facing the air blower 10, the first detected temperature is detected to be lower than the first target temperature. This also makes it possible to set the set temperature after printing is completed based on the first detected temperature at the end of printing, which is lower than the first target temperature, which is the set temperature during printing.

[0066] Furthermore, in the present embodiment, the control unit 12 sets the set temperature after printing to the same temperature as the first detected temperature at the end of printing based on the first detected temperature at the end of printing. However, this is not limited to this. For example, the control unit 12 may set the set temperature after printing to a temperature different from the first detected temperature at the end of printing. Specifically, the control unit 12 may set the set temperature after printing to a predetermined temperature lower than the first detected temperature at the end of printing. The predetermined temperature is determined in advance through experiments and stored in the memory unit 12a. For example, the predetermined temperature is 3°C. According to this printing device 1, the control unit 12 sets the set temperature after printing to a predetermined temperature lower than the first detected temperature at the end of printing, thereby achieving the same effects as the present embodiment and further reducing the power consumption of the printing device 1.

[0067] Furthermore, in the present embodiment, the control unit 12 operates the fan 10a for a predetermined period after printing is completed to continue blowing air from the blower unit 10, but this is not limited to this. For example, after printing is completed in step S7, the control unit 12 may reduce the airflow rate of the fan 10a, among the multiple fans 10a, that faces the medium M supported in the support area. According to this printing device 1, since the airflow rate of the fan 10a that faces the medium M is reduced, in addition to the same effects as the present embodiment, the power consumption of the printing device 1 can be further reduced. [Explanation of symbols]

[0068] 1...printing device, 2...supply section, 3...guide, 4...conveying section, 4a...drive roller, 4b...follower roller, 5...platen, 6...printing section, 7...medium support section, 7a...bending section, 8...heating section, 8a...electric wire heater, 9...temperature detection section, 9a...first temperature detection section, 9b...second temperature detection section, 10...blowing section, 10a...fan, 11...winding section, 12...control section, 12a...memory section, F...conveying direction, M...medium, M1...first side, M2...second side, R1...roll body, R2...winding roll body.

Claims

1. a printing unit that applies a liquid to print on a medium; a medium support portion that supports the medium to which the liquid has been applied; a heating unit that heats the medium supported by the medium support unit; a temperature detection unit that detects the temperature of the medium or the medium support unit; a control unit that performs feedback control on the heating unit so that a detected temperature detected by the temperature detection unit becomes a set temperature; Equipped with The printing device, wherein the control unit sets the set temperature after printing to be lower than the set temperature during printing.

2. the control unit sets the set temperature after printing is completed based on the detected temperature during printing. The printing device of claim 1 .

3. the control unit sets the set temperature after printing is completed based on the detected temperature at the time of printing completion. The printing device according to claim 2 .

4. the control unit sets the set temperature after printing to a predetermined temperature lower than the detected temperature at the time of printing completion. The printing device according to claim 3 .

5. the temperature detection unit detects the temperature of the medium support unit at a position where the medium is supported; The printing device of claim 1 .

6. The control unit performs PID control of the heating unit. The printing device of claim 1 .

7. a blower unit disposed opposite the medium support unit and blowing air toward the medium support unit, wherein the control unit continues blowing air from the blower unit for a predetermined period after printing is completed. The printing device of claim 1 .

8. the air blowing unit has a plurality of fans arranged in a width direction of the medium support unit, and the control unit reduces the airflow rate of the fans facing the medium after printing is completed. The printing device according to claim 7.

9. the heating unit heats the medium via the medium support unit; The printing device of claim 1 .

10. The heating unit is an electric wire heater. The printing device according to claim 9.

Images