Printing device and printing control method

Abstract

The present application provides a printing device and a printing control method, aiming at printing with stable image quality even if the moving time of a carriage is long. The printing device includes a flushing determination unit that determines whether to perform flushing, and a storage unit that stores a condition in which the landing error of ink droplets is equal to or less than a predetermined allowable value. In the flushing determination unit, based on print data printed in a round trip movement of the carriage, a hypothetical turnaround position in the round trip movement is calculated, a hypothetical turnaround time is calculated, which is a one-way turnaround movement time required when the carriage turns around at the hypothetical turnaround position, a threshold value is calculated, which is a longest non-ejection time in which printing can be stably performed at an ambient temperature determined by a thermometer, it is determined whether the hypothetical turnaround time exceeds the threshold value, in the case where the hypothetical turnaround time exceeds the threshold value, a position at which the one-way turnaround movement time is longer than the hypothetical turnaround time is set as a turnaround position in the round trip movement, and it is determined to perform flushing in a loop.

Description

TECHNICAL FIELD

[0001] The present application relates to a printing apparatus and a printing control method. BACKGROUND

[0002] Conventionally, an inkjet-type printing apparatus that prints an image or the like on a medium by ejecting a liquid such as ink from a nozzle-equipped ejecting head toward a surface 23a of a medium such as paper or cloth has been used. In such a printing apparatus, in order to prevent poor ejection of ink from the nozzle, a maintenance section that performs maintenance of the ejecting head is provided.

[0003] In the case of printing a print, the image quality must be stable at any position of the printing medium. In a printing apparatus that prints by ejecting ink from a nozzle, a nozzle that has not ejected ink for a certain time or more has water evaporate from the tip of the nozzle and the viscosity of the ink becomes high, becoming a clogged state. Therefore, ink cannot be normally ejected from a nozzle that has a low ejection frequency, and the printing quality can be reduced.

[0004] The state in which ink cannot be normally ejected includes a phenomenon in which ink can be ejected but the landing error is worse than the allowable value. There is a tendency for the landing error to become larger as the standing time of the nozzle in which ink is not ejected becomes longer. Therefore, in the maintenance section in the printing apparatus, by performing a flushing operation that ejects ink toward an ink receiving section different from the printing, clogging of the nozzle is prevented or eliminated. The printing apparatus described in Patent Document 1 has an ink receiving section that receives ink at the time of the flushing operation on both the start side and the full side. A technique is described in which, in order to improve productivity, whether or not to perform the flushing operation is determined in accordance with the paper width, the moving direction of the carriage at the start of printing, the wait time between paths, and the like.

[0005] Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 2000-158673

[0006] However, particularly in the case of a large printing apparatus in which the moving time of the carriage is long, there is a problem in that the standing time of the nozzle in which ink is not ejected becomes longer, and the stability is reduced in the latter half of the outgoing path or the next loop path. SUMMARY

[0007] One aspect of the present application is a printing device including: an inkjet recording head that ejects liquid droplets from a nozzle toward a print medium; a carriage that supports the recording head and performs reciprocating movement in a first direction; a thermometer that measures an ambient temperature in the vicinity of the nozzle; a control section that controls the reciprocating movement of the carriage and the ejection of liquid droplets from the nozzle; a flushing determination section that determines whether flushing is performed in a loop of the reciprocating movement of the carriage; and a storage section that stores a correspondence relationship between a non-ejection time, which is a time during which liquid droplets are not ejected from the nozzle, and a temperature, which is a condition under which a landing error of liquid droplets ejected from the nozzle is equal to or less than a prescribed allowable value, which is obtained in advance. In the flushing determination section, in one reciprocating movement of the carriage, a hypothetical turnaround position in the reciprocating movement of the carriage is calculated based on print data printed in the one reciprocating movement, a hypothetical reciprocating time, which is a time of one reciprocating movement of the carriage required when the carriage turns around at the hypothetical turnaround position, is calculated, a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer, is calculated, it is determined whether the hypothetical reciprocating time exceeds the threshold value, and in the case where the hypothetical reciprocating time exceeds the threshold value, a position at which the time of one reciprocating movement of the carriage is longer than the hypothetical reciprocating time is set as a turnaround position in the reciprocating movement of the carriage, and it is determined that flushing is performed in the loop in which the carriage moves.

[0008] One aspect of the present application is a printing control method for a printing device including: an inkjet recording head that ejects liquid droplets from a nozzle toward a print medium; a carriage that supports the recording head and performs reciprocating movement in a first direction; a thermometer that measures an ambient temperature in the vicinity of the nozzle; and a control section that controls the reciprocating movement of the carriage and the ejection of liquid droplets from the nozzle. In the printing control method, it is determined whether flushing is performed in a loop of the reciprocating movement of the carriage, a correspondence relationship between a non-ejection time, which is a time during which liquid droplets are not ejected from the nozzle, and a temperature, which is a condition under which a landing error of liquid droplets ejected from the nozzle is equal to or less than a prescribed allowable value, which is obtained in advance, is stored, in the determination, in one reciprocating movement of the carriage, a hypothetical turnaround position in the reciprocating movement of the carriage is calculated based on print data printed in the one reciprocating movement, a hypothetical reciprocating time, which is a time of one reciprocating movement of the carriage required when the carriage turns around at the hypothetical turnaround position, is calculated, a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer, is calculated, it is further determined whether the hypothetical reciprocating time exceeds the threshold value, and in the case where the hypothetical reciprocating time exceeds the threshold value, a position at which the time of one reciprocating movement of the carriage is longer than the hypothetical reciprocating time is set as a turnaround position in the reciprocating movement of the carriage, and it is determined that flushing is performed in the loop in which the carriage moves. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 FIG. 1 is a schematic diagram showing the overall configuration of a printing device according to an embodiment.

[0010] Figure 2is a plan view showing the configuration of the printing section and the maintenance section.

[0011] Figure 3 is a side view showing the configuration of the printing section and the maintenance section.

[0012] Figure 4 is an electrical block diagram showing the electrical configuration of the printing device.

[0013] Figure 5 is a graph showing the relationship between the idle running time at each temperature and the landing error when the carriage moving speed is fast.

[0014] Figure 6 is a graph showing the relationship between the idle running time at each temperature and the landing error when the carriage moving speed is slow.

[0015] Figure 7 is a flowchart showing the operation of the printing device of the embodiment.

[0016] Figure 8 is an explanatory view showing the operation of the modification.

[0017] BRIEF DESCRIPTION OF DRAWINGS

[0018] 1 • • control section, 2 • • interface section, 3 • • CPU, 4 • • control circuit, 5 • • storage section, 6 • • external device, 7 • • detector group, 8 • • flushing determination section, 10 • • medium supply section, 11 • • supply shaft section, 12 • • bearing section, 20 • • medium conveying section, 21 • • conveying roller, 22 • • conveying roller, 23 • • belt (support section), 24 • • belt rotating roller, 25 • • belt driving roller, 26 • • conveying roller, 27 • • drying unit, 28 • • conveying roller, 29 • • adhesive layer, 30 • • medium recovery section, 31 • • winding shaft section, 32 • • bearing section, 40 • • printing section, 41 • • nozzle, 42 • • print head (recording head), 43 • • carriage, 45 • • thermometer, 50 • • cleaning unit, 51 • • cleaning section, 52 • • pressing section, 53 • • moving section, 54 • • cleaning tank, 55 • • squeegee, 56 • • air cylinder, 57 • • ball bushing, 58 • • cleaning roller, 60 • • medium adhesion section, 61 • • pressing roller, 62 • • pressing roller driving section, 63 • • roller support section, 70 • • maintenance section, 71 • • suction section, 72 • • cover, 74 • • wiping section, 75 • • squeegee, 77 • • flushing section, 81 • • cover section, 82 • • cover, 92 • • frame section, 93 • • carriage conveying section, 94 • • lifting device, 95 • • printing medium, 99 • • ground, 100 • • printing device. DETAILED DESCRIPTION

[0019] Next, an embodiment of the present application will be described with reference to the drawings.

[0020] Figures 1-8 is one example of a mode of carrying out the application, in the figure, portions to which the same reference symbols are assigned represent the same components. In addition, a part of the configuration is appropriately omitted in each figure to simplify the drawing. Also, the size, shape, thickness, and the like of the components are appropriately exaggerated.

[0021] Further, in the figure, for the sake of convenience of explanation, an X axis, a Y axis, and a Z axis are illustrated as three axes orthogonal to each other, the front end side of the arrow illustrating the axis direction is set to the + side, and the base end side is set to the - side. Further, hereinafter, the direction parallel to the X axis is referred to as the X axis direction, the direction parallel to the Y axis is referred to as the Y axis direction, and the direction parallel to the Z axis is referred to as the Z axis direction.

[0022] Figure 1 is a schematic view showing the overall configuration of a printing device 100 of an embodiment of the present application. In the present embodiment, an inkjet-type printing device 100 that performs printing on a printing medium 95 by forming an image or the like on the printing medium 95 is described as an example.

[0023] The printing device 100 is provided with a medium supply section 10, a medium conveying section 20, a medium recovery section 30, a printing section 40, a cleaning unit 50, a medium adhesion section 60, and the like. Further, a control section 1 that controls the entire printing device 100 is provided.

[0024] The control section 1 is configured by a CPU, a RAM, a ROM, and the like, and performs various controls. The CPU is a so-called central arithmetic processing device, and performs various programs to realize various functions. The RAM serves as a work area, a storage area of the CPU, and the ROM stores an operating system, a program executed by the CPU.

[0025] Each part of the printing device 100 is mounted to a frame section 92.

[0026] The medium supply section 10 supplies the printing medium 95 on which an image is formed to the printing section 40 side. As the printing medium 95, for example, cloth such as cotton, wool, chemical fiber, and blended fabric is used. The medium supply section 10 has a supply shaft section 11 and a bearing section 12. The supply shaft section 11 is formed in a cylindrical shape or a columnar shape, and is provided so as to be able to rotate in the circumferential direction. The printing medium 95 in a band shape is wound in a roll shape on the supply shaft section 11. The supply shaft section 11 is detachably mounted to the bearing section 12. The printing medium 95 in a state of being wound in advance on the supply shaft section 11 is mounted to the bearing section 12 together with the supply shaft section 11.

[0027] The bearing portion 12 supports both ends of the axial direction of the supply shaft portion 11 so as to be rotatable. The medium supply portion 10 has a rotation driving portion that rotationally drives the supply shaft portion 11. The rotation driving portion rotates the supply shaft portion 11 in a direction in which the printed medium 95 is fed out. The operation of the rotation driving portion is controlled by the control portion 1.

[0028] The medium conveying portion 20 conveys the printed medium 95 from the medium supply portion 10 to the medium recovery portion 30. The medium conveying portion 20 includes a conveying roller 21, a conveying roller 22, a belt 23, a belt rotation roller 24, a belt driving roller 25, a conveying roller 26, a drying unit 27, and a conveying roller 28. The conveying rollers 21 and 22 relay the printed medium 95 from the medium supply portion 10 to the belt 23.

[0029] The belt 23 connects both end portions of the belt in a belt shape to form a ring shape, and is hung on the belt rotation roller 24 and the belt driving roller 25. The belt 23 is held in a state in which a predetermined tension is applied, so that a portion between the belt rotation roller 24 and the belt driving roller 25 is parallel to the ground 99. An adhesive layer 29 that adheres the printed medium 95 is provided on a surface 23a of the belt 23. The belt 23 supports the printed medium 95 that is supplied from the conveying roller 22 and is adhered to the adhesive layer 29 by the medium adhesion portion 60 described later. Thus, cloth or the like having stretchability can be regarded as the printed medium 95.

[0030] The belt rotation roller 24 and the belt driving roller 25 support an inner peripheral surface 23b of the belt 23. Alternatively, a support portion that supports the belt 23 can be provided between the belt rotation roller 24 and the belt driving roller 25.

[0031] The belt driving roller 25 has a motor that rotationally drives the belt driving roller 25. If the belt driving roller 25 is rotationally driven, the belt 23 rotates in conjunction with the rotation of the belt driving roller 25, and the belt rotation roller 24 rotates by the rotation of the belt 23. By the rotation of the belt 23, the printed medium 95 supported by the belt 23 is conveyed in a predetermined +X-axis direction, and an image is formed on the printed medium 95 by the printing portion 40 described later.

[0032] In the present embodiment, the surface 23a of the belt 23 supports the printed medium 95 on the +Z-axis side opposite to the printing portion 40, and the printed medium 95 is conveyed from the belt rotation roller 24 side to the belt driving roller 25 side together with the belt 23. In addition, on the -Z-axis side of the surface 23a of the belt 23 opposite to the cleaning unit 50, only the belt 23 moves from the belt driving roller 25 side to the belt rotation roller 24 side.

[0033] The conveying roller 26 peels the printed medium 95 on which the image is formed from the adhesive layer 29 of the belt 23. The conveying rollers 26 and 28 relay the printed medium 95 from the belt 23 to the medium recovery portion 30.

[0034] The medium take-up section 30 takes up the print medium 95 transported by the medium transport section 20. The medium take-up section 30 has a winding shaft section 31 and a bearing section 32. The winding shaft section 31 is formed in a cylindrical shape or a columnar shape, and is provided so as to be rotatable in a circumferential direction. The print medium 95 in a band shape is wound in a roll shape around the winding shaft section 31. The winding shaft section 31 is attached so as to be detachable with respect to the bearing section 32. Thus, the print medium 95 in a state of being wound around the winding shaft section 31 can be detached together with the winding shaft section 31.

[0035] The bearing section 32 supports both ends in the axial direction of the winding shaft section 31 so as to be rotatable. The medium take-up section 30 has a rotation drive section that rotationally drives the winding shaft section 31. The rotation drive section rotates the winding shaft section 31 in a direction in which the print medium 95 is wound. The operation of the rotation drive section is controlled by the control section 1.

[0036] In the present embodiment, a drying unit 27 is provided between the transport roller 26 and the transport roller 28. The drying unit 27 dries the image formed on the print medium 95. The drying unit 27 includes, for example, an IR heater, and by driving the IR heater, the image formed on the print medium 95 can be dried in a short time. Thus, the print medium 95 in a band shape on which the image is formed can be wound around the winding shaft section 31.

[0037] The medium adhesion section 60 causes the print medium 95 to adhere to the belt 23. The medium adhesion section 60 is disposed on the -X axis side, which is more upstream than the printing section 40, with respect to the transport direction of the print medium 95. The medium adhesion section 60 has a press roller 61, a press roller drive section 62, and a roller support section 63. The press roller 61 is formed in a cylindrical shape or a columnar shape, and is provided so as to be rotatable in a circumferential direction. The press roller 61 is disposed so that the axial direction intersects the transport direction, in a manner of rotating in the direction along the transport direction. The roller support section 63 is provided on the inner circumferential surface 23b side of the belt 23 opposite the press roller 61 with the belt 23 interposed therebetween.

[0038] The press roller drive section 62 presses the press roller 61 toward the -Z axis side in the vertical direction, while moving the press roller 61 in the +X axis direction of the transport direction and the -X axis direction opposite the transport direction. The print medium 95 transported from the transport roller 22 and overlapping the belt 23 is pressed against the belt 23 between the press roller 61 and the roller support section 63. Thus, the print medium 95 can be reliably adhered to the adhesive layer 29 provided on the surface 23a of the belt 23, and the generation of lift of the print medium 95 on the belt 23 can be prevented.

[0039] The printing apparatus 100 is provided with a cleaning unit 50 for cleaning the belt 23. In detail, the cleaning unit 50 is configured of a cleaning section 51, a pressing section 52, and a moving section 53. The moving section 53 is capable of moving the cleaning unit 50 integrally along the floor 99 and fixing it to a prescribed position. The cleaning unit 50 is disposed between the belt rotation roller 24 and the belt drive roller 25 in the X-axis direction.

[0040] The pressing section 52 is, for example, a lifting device configured of a cylinder 56 and a ball bushing 57, and is capable of moving the cleaning section 51 provided to the upper portion thereof to a cleaning position and a retreat position. The cleaning position is a position at which the cleaning roller 58 and the squeegee 55 abut against the belt 23. The retreat position is a position at which the cleaning roller 58 and the squeegee 55 are separated from the belt 23. The cleaning section 51 cleans the surface 23a of the belt 23 hanging in a state in which a prescribed tension is applied between the belt rotation roller 24 and the belt drive roller 25 from the -Z-axis direction at the cleaning position. In addition, Figure 1 A case in which the cleaning section 51 is disposed at the cleaning position by being raised is shown.

[0041] The cleaning section 51 has a cleaning tank 54, a cleaning roller 58, and a squeegee 55. The cleaning tank 54 is a tank that stores a cleaning liquid for cleaning ink, foreign matter, and the like adhering to the surface 23a of the belt 23, and the cleaning roller 58 and the squeegee 55 are disposed inside the cleaning tank 54. As the cleaning liquid, for example, water or a water-soluble solvent such as alcohol can be used, and a surfactant or an antifoaming agent can be added as necessary.

[0042] The -Z-axis side of the cleaning roller 58 is dipped in the cleaning liquid stored in the cleaning tank 54. If the cleaning roller 58 is rotated at the cleaning position, the cleaning liquid is supplied to the surface 23a of the belt 23, and the cleaning roller 58 and the belt 23 slide. Thus, ink, fibers of cloth as the printing medium 95, and the like adhering to the belt 23 are removed by the cleaning roller 58.

[0043] The squeegee 55 can be formed of a flexible material such as silicone rubber, for example. The squeegee 55 is disposed at a position further toward the downstream side than the cleaning roller 58 in the conveyance direction of the belt 23. By the belt 23 and the squeegee 55 sliding, the cleaning liquid remaining on the surface 23a of the belt 23 is removed.

[0044] The printing section 40 ejects ink as a liquid in a droplet manner toward the printing medium 95 held to the belt 23.

[0045] Figure 2 is a plan view showing the configuration of the printing section 40 and the maintenance section 70. Figure 3 is a side view showing the configuration of the printing section and the maintenance section.

[0046] As Figure 2 and Figure 3As shown, the printing section 40 has a carriage 43 that mounts the print head 42, and the like. The print head 42 has a nozzle 41 that ejects ink. In addition, the printing section 40 has a thermometer 45 that measures the ambient temperature in the vicinity of the nozzle 41. The print head 42 is moved back and forth in the Y-axis direction by a carriage transport section 93 described later. Specifically, the carriage 43 supports the print head 42 and moves back and forth in the Y-axis direction.

[0047] The print head 42 corresponds to one example of a recording head.

[0048] The Y-axis direction corresponds to one example of the first direction.

[0049] The carriage transport section 93 moves the print head 42 along with the carriage 43 back and forth in the Y-axis direction. The carriage transport section 93 is provided on the +Z-axis direction side of the belt 23. The carriage transport section 93 has a pair of carriage transport sections 93a, 93b that extend in the Y-axis direction, and a carriage position detection device, and the like, provided along the carriage transport sections 93a, 93b.

[0050] The carriage transport sections 93a, 93b are erected between frame sections 92a, 92b provided on the outer side of the belt 23 in the X-axis direction. The carriage transport sections 93a, 93b support the carriage 43. The carriage 43 is guided by the carriage transport sections 93a, 93b so as to be supported by the carriage transport sections 93a, 93b in a state in which it can move back and forth in the Y-axis direction. The carriage position detection device extends along the carriage transport sections 93a, 93b and can detect the position of the carriage 43 in the Y-axis direction.

[0051] The carriage transport section 93 has a movement mechanism and a power source, which are not shown. As the movement mechanism, for example, a mechanism that combines a ball screw and a ball nut, or a linear guide mechanism, and the like, can be used. In addition, a motor is provided in the carriage transport section 93 as a power source for moving the carriage 43 in the Y direction. As the motor, various motors such as a step motor, a servo motor, a linear motor, and the like, can be used. If the motor is driven by control of the control section 1, the print head 42 moves back and forth in the Y-axis direction along with the carriage 43.

[0052] The maintenance section 70 and the cover section 81 will be described. The maintenance section 70 and the cover section 81 are provided on the one end side of the belt 23 in the Y-axis direction in which the print head 42 moves back and forth. When viewed from the top in the +Z-axis direction, the maintenance section 70 and the cover section 81 are provided in the Y-axis direction at a position that overlaps the print head 42 that moves back and forth.

[0053] The printing device 100 has a support section that supports the print medium 95, and a plurality of flush sections 77 that are arranged on both sides of the support section in the Y-axis direction and receive ink when flushing is performed. Specifically, the maintenance section 70 has at least one flush section 77a, and at least one flush section 77b is provided on the other end side of the belt 23 in the Y-axis direction.

[0054] In the present embodiment, as the plurality of maintenance sections 70 include: a suction section 71 that suctions the print head 42, a wiping section 74 that removes liquid, and a flushing section 77a that ejects liquid from the nozzle 41 of the print head 42. The maintenance sections 70 and the cover section 81 are arranged in the order of the cover section 81, the suction section 71, the wiping section 74, and the flushing section 77a from the end in the -Y axis direction toward the +Y axis direction. The maintenance sections 70 and the cover section 81 are provided with a lifting device 94 configured of a pneumatic cylinder or the like, and are raised to an abutting position or a close position in which the print head 42 is close to the abutting position when a maintenance operation is performed.

[0055] The cover section 81 is a device that covers the print head 42. Ink ejected from the nozzle 41 provided in the print head 42 sometimes has volatility, and if the solvent of the ink present in the print head 42 volatilizes from the nozzle 41, the viscosity of the ink changes, and the nozzle 41 sometimes clogs. The cover section 81 is provided with a cover body 82, and by covering the print head 42 with the cover body 82, clogging of the nozzle 41 is prevented.

[0056] The suction section 71 is a device that covers the print head 42 and suctions ink in the print head 42. The suction section 71 has a cover body 72 and a negative pressure pump not shown, and by applying negative pressure to the inside of the cover body 72 and suctioning ink in the print head 42 in a state in which the print head 42 is covered with the cover body 72, it is possible to remove bubbles or foreign matter or the like in the print head 42. By this, it is possible to recover or prevent ejection failure caused by bubbles or foreign matter.

[0057] The wiping section 74 is a device that wipes the print head 42. If solidified ink or foreign matter is attached to the print head 42, sometimes ejection failure occurs in which liquid droplets land at a place other than a predetermined place on the print medium 95. The wiping section 74 is provided with a wiper 75 and a wiping motor that moves the wiper 75 in the X axis direction. The wiping section 74, by a wiping operation in which the wiper 75 wipes ink or foreign matter attached to the print head 42, makes it possible to recover or prevent ejection failure.

[0058] The flushing section 77 is a device that captures liquid droplets ejected from the nozzle 41. The flushing section 77 is provided with a flushing box having porous fibers such as felt, and when the ink flow path in the print head 42 is cleaned, it captures liquid droplets ejected from the nozzle 41 provided in the print head 42. In the case where the ink in the print head 42 is increased in viscosity or solid matter is mixed in, by a flushing operation in which liquid droplets are ejected from the nozzle 41, the increased viscosity ink or the solid matter is removed to adjust the state of the ink. By this, it is possible to recover or prevent ejection failure caused by increased viscosity ink or solid matter.

[0059] The suction section 71 and the cover section 81 can be integrated.

[0060] Figure 4 is an electrical block diagram showing an electrical configuration of the printing device.

[0061] The printing device 100 is provided with a control section 1. The control section 1 is a control unit for performing control of the printing device 100. The control section 1 is configured including a control circuit 4, an interface section 2, a CPU 3, and a storage section 5. The interface section 2 is used for transmitting and receiving data between an external device 6 such as a computer that processes an image and the printing device 100. The CPU 3 is an arithmetic processing device for performing input signal processing from various detector groups 7 and control of the entire printing device 100.

[0062] The storage section 5 is used for securing a region in which a program of the CPU 3 is stored and a job region and the like, and has, for example, a RAM, an EEPROM (Electrically Erasable Programmable Read-Only Memory), a flash memory, or a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0063] The CPU 3 controls various motors provided in the belt drive roller 25 via the control circuit 4, and moves the printing medium 95 in the X-axis direction. The CPU 3 controls various motors provided in the carriage conveyance section 93 via the control circuit 4, and moves the carriage 43 on which the print head 42 is mounted in the Y-axis direction. The CPU 3 controls a voltage of a piezoelectric element provided in the print head 42 via the control circuit 4, and ejects a liquid droplet from the nozzle 41 toward the printing medium 95. In the present embodiment, the printing device 100 does not determine a moving distance in the Y-axis direction of the carriage 43 based on a fixed distance in which the moving distance is determined in advance, but determines the moving distance, that is, a turnaround position of the shuttle movement, based on printing data printed by one round trip, and thereby improves productivity of printing.

[0064] Here, the X-axis direction corresponds to one example of a second direction orthogonal to the first direction.

[0065] The CPU 3 controls the lifting device 94 and the negative pressure pump provided in the suction section 71 via the control circuit 4, and performs maintenance of the print head 42. The CPU 3 controls the lifting device 94 provided in the wiping section 74 and a motor that moves the squeegee 75 via the control circuit 4, and performs maintenance of the print head 42. The CPU 3 controls the lifting device 94 provided in the flushing section 77 via the control circuit 4, and performs maintenance of the print head 42. In addition, the CPU 3 also controls various devices not shown via the control circuit 4.

[0066] Figure 5is a graph showing the relationship between the idle running time when the moving speed of the carriage 43 is fast and the landing error. The broken line graphs of the respective marks show the relationship between the idle running time and the landing error at the temperatures TA, TB, and TC, respectively. Specifically, for example, TA is 35 degrees Celsius, TB is 30 degrees Celsius, and TC is 25 degrees Celsius. As shown in Figure 5 , the higher the ambient temperature, the faster the evaporation of the solvent contained in the ink, and thus there is a tendency for the landing error to become large.

[0067] Here, the idle running time refers to the time during which the carriage 43 moves without ejecting a droplet from the nozzle 41, and is the non-ejection time. Specifically, in a case where the allowable error, which is the allowable value of the landing error of the ink, is about 80 μm, the longest non-ejection time that is allowable at the temperature TB is about 5 sec, and the longest non-ejection time that is allowable at the temperature TA is less than 3 sec. In addition, the time when the carriage 43 moves at the maximum amplitude is referred to as the maximum carriage round trip time. In a case where the landing error does not exceed the allowable error within the idle running time within the maximum carriage round trip time, flushing in the circuit can not be performed. For the temperature between the reference temperatures TA and TC, the idle running time and the landing error are calculated by linear interpolation to become the idle running allowable time within the allowable error, and it is determined on the basis of the idle running allowable time whether or not to perform flushing in the circuit.

[0068] the moving speed of the carriage 43 corresponding to Figure 5 is set to the first speed, the correspondence relationship between the non-ejection time at this time and the temperature is defined as the first correspondence relationship, and the printing mode is defined as the first mode.

[0069] The moving speed when the carriage 43 performs printing at a fixed speed is denoted as the CR speed. The distance through which the carriage 43 moves in one way is denoted as the path width. The value obtained by adding up the distances through which the moving speed of the carriage 43 is accelerated or decelerated in one way is denoted as the acceleration / deceleration printing width. In addition, the value obtained by adding up the times during which the carriage is accelerated or decelerated in one way is defined as the acceleration / deceleration time.

[0070] In one round trip movement of the carriage 43, the return position when the carriage 43 is turned back after moving the path width corresponding to the printing data on the basis of the printing data that is printed in the one round trip movement is defined as the assumed return position in the round trip movement of the carriage 43. At this time, the round trip movement time of the carriage 43 required when the carriage 43 is turned back at the assumed return position, that is, the assumed round trip time Time elapse is denoted by the following mathematical expression (1).

[0071] [Num 1]

[0072]

[0073] The longest permissible non-ejection time at temperature TB is denoted as Time. ref0 The longest non-ejection time allowed at temperature TC will be denoted as Time. ref1 Furthermore, temperature TB is represented as Temp. ref0 Temperature TC is represented as Temp ref1 At this point, the threshold Time is the longest non-ejection time at which the landing error of the droplets ejected from nozzle 41 at ambient temperature T satisfies the condition of being below the allowable value. thresh If we consider the approach based on linear interpolation, it is expressed as the following mathematical formula (2).

[0074]

Number 2

[0075]

[0076] The printing apparatus 100 has a rinsing determination unit 8 that determines whether rinsing is performed in the reciprocating motion loop of the carriage 43. The printing apparatus 100 has a storage unit 5 that stores a pre-determined correspondence between the non-ejection time (the time during which droplets are not ejected from the nozzle 41) and the temperature, i.e., the condition that the landing error of the droplets ejected from the nozzle is below a predetermined allowable value.

[0077] During one round trip of the carriage 43, the washing determination unit 8 calculates the assumed return position, the assumed round trip time, and the threshold Time based on the printing data printed during that round trip. thresh The threshold Time thresh It is the longest non-ejection time that meets the conditions at ambient temperature T.

[0078] Furthermore, the flushing determination unit 8 determines the assumed round-trip time. elapse Has the threshold Time been exceeded? thresh In this embodiment, during the acceleration of the path in the reciprocating motion of the carriage 43, rinsing is performed from the printhead 42 to the rinsing section 77a. Therefore, when rinsing is not performed in the reciprocating motion loop of the carriage 43, the non-ejection time during the reciprocating motion of the carriage 43 when the nozzle 41 does not eject ink based on the printing data is the time from the rinsing performed in the path of the carriage 43 to the rinsing performed in the path of the next carriage 43, which is approximately equal to the reciprocating motion time of the carriage 43. Therefore, by comparing the assumed reciprocating time Time... elapse With threshold Time thresh This allows us to determine whether rinsing is necessary during the loop movement of carriage 43. Furthermore, assuming a round-trip time of Time... elapse Time exceeding the threshold thresh In the case of a location where the round-trip time is longer than the assumed round-trip time, i.e., the round-trip time is longer than the threshold Time, the location is considered to have a longer round-trip time.thresh The long position is set to a turnaround position in the back-and-forth movement of the carriage 43, and the flushing is performed in the loop of the movement of the carriage 43. In addition, in the present embodiment, in the case where the flushing is performed in the loop of the back-and-forth movement of the carriage 43, the flushing is performed at the acceleration of the carriage 43 in the loop. In the present embodiment, it will be assumed that the back-and-forth time Time elapse The non-ejection time is considered synonymous with the non-ejection time in which the nozzle 41 does not eject ink based on the printing data in the back-and-forth movement of the carriage 43.

[0079] The flushing determination section 8 is realized by the cooperation of software and hardware by the CPU 3 executing the control program stored in the storage section 5 in the control section 1. The flushing operation is realized by the control section 1 controlling the carriage transport section 93, the print head 42, the flushing section 77, and the like via the control circuit 4.

[0080] Figure 6 is a graph showing the relationship between the idle running time when the movement speed of the carriage 43 is slow and the landing error.

[0081] The movement speed of the carriage 43 corresponding to Figure 6 is set to a second speed, the corresponding relationship between the non-ejection time at this time and the temperature is defined as a second corresponding relationship, and the printing mode is defined as a second mode.

[0082] The broken line graphs of the respective marks respectively show the relationship between the idle running time and the landing error at the temperatures TA, TB, and TC. Specifically, for example, TA is 35 degrees Celsius, TB is 30 degrees Celsius, and TC is 25 degrees Celsius.

[0083] In the case where Figure 6 the landing error of the ejection of the droplet from the nozzle 41 becomes the shortest non-ejection time that is the allowable error as the prescribed allowable value is when the non-ejection time is about 8 sec at the environmental temperature T of TA, if it is a non-ejection time shorter than that, the landing error is smaller than the allowable error in whichever of the temperatures TA, TB, and TC. In the relationship between the idle running time and the landing error shown in Figure 6 , the maximum idle running time is slightly shorter than the shortest non-ejection time of about 8 sec. That is, in the case where the movement speed of the carriage 43 is the second movement speed, the landing error is always smaller than the allowable error. Therefore, the operation guarantee temperature is TA to TC, and in the case where the movement speed of the carriage 43 is the second movement speed, the flushing operation does not need to be performed in the loop.

[0084] The flushing determination section 8 of the printing device 100 confirms the movement speed of the carriage 43 at the time of printing, performs the determination of whether the flushing operation needs to be performed in the loop in the case where it corresponds to the first mode, and does not perform the flushing operation in the loop in the case where it corresponds to the second mode.

[0085] Figure 7 is a flowchart illustrating the operation of the printing device 100, and specifically, a printing control method of the embodiment. The flushing determination section 8 of the printing device 100 determines the printing mode based on the CR speed, which is a preset moving speed of the carriage 43 (step SA1). Specifically, for example, in a case where the CR speed is 600 cps, the CR speed corresponds to one example of the first speed, which is a high speed, and the printing mode is the first mode. Further, for example, in a case where the CR speed is 300 cps, the CR speed corresponds to one example of the second speed, which is a low speed, and the printing mode is the second mode.

[0086] In a case where the printing mode is the first mode, the flushing determination section 8 calculates the assumed round trip time Time elapse (step SA2) based on mathematical expression (1).

[0087] The flushing determination section 8 calculates the threshold value Time thresh (step SA3) based on mathematical expression (2).

[0088] Here, the correspondence relationship between the non-ejection time, which is the time during which no droplet is ejected from the nozzle, and the temperature, i.e., the condition under which the landing error of the droplet ejected from the nozzle is equal to or less than a predetermined allowable value, is, for example, as shown in FIG. 6. Figure 5

[0089] Next, the value of the calculated assumed round trip time Time elapse is compared with the value of the threshold value Time thresh (step SA4).

[0090] In a case where the value of the assumed round trip time Time elapse is greater than the value of the threshold value Time thresh (step SA4: YES), the printing device 100 performs the flushing operation in the loop while the carriage 43 is moving back and forth (step SA5).

[0091] In a case where the value of the assumed round trip time Time elapse is equal to or less than the value of the threshold value Time thresh (step SA4: NO), the printing device 100 does not perform the flushing operation in the loop while the carriage 43 is moving back and forth (step SA6).

[0092] Further, in a case where the printing mode is the second mode, the printing device 100 does not perform the flushing operation in the loop while the carriage 43 is moving back and forth (step SA6).

[0093] ​In the present embodiment, the next step SA2 of the step SA1 is implemented, but the following determination process can be added between the step SA1 and the step SA2: the ambient temperature T is acquired using the thermometer 45, it is determined whether the ambient temperature T is a prescribed temperature or more, if it is determined that it is the prescribed temperature or more, it proceeds to the step SA2, and if it is determined that it is less than the prescribed temperature, it proceeds to the step SA6. In the case where the time required for the carriage 43 to be moved back and forth in the maximum distance in the first direction in which the carriage 43 can be moved is set to be the maximum carriage back-and-forth time at the moving speed of the carriage in the selected print mode, the prescribed temperature is the ambient temperature at which the landing error becomes the allowable error or more when the non-ejection time is the maximum carriage back-and-forth time in the correspondence relation between the non-ejection time and the temperature. For example, in the relation between the non-ejection time, the landing error, and the temperature shown in FIG. 9, since the landing error when the idle time is the maximum carriage back-and-forth time is the allowable error or more, the temperature TA is determined to be the prescribed temperature or more, and since the landing error when the idle time is the maximum carriage back-and-forth time is less than the allowable error, the temperatures TB and TC are determined to be less than the prescribed temperature. Figure 5

[0094] Specifically, the printing device 100 includes: the print head 42 that ejects a droplet from the nozzle 41 toward the print medium 95; the carriage 43 that supports the print head 42 and moves back and forth in the first direction; and the thermometer 45 that measures the ambient temperature in the vicinity of the nozzle. The printing device 100 includes: the control section 1 that controls the back-and-forth movement of the carriage 43 and the ejection of the droplet from the nozzle 41; and the flushing determination section 8 that determines whether to implement flushing in the loop of the back-and-forth movement of the carriage. Further, the printing device 100 includes a storage section that stores the correspondence relation between the non-ejection time, which is the time during which the droplet is not ejected from the nozzle 41, and the temperature, which is the condition under which the landing error of the droplet ejected from the nozzle 41 is a prescribed allowable value or less, that is calculated in advance.

[0095] The flushing determination section 8 calculates a hypothetical turnaround position in the back-and-forth movement of the carriage 43 based on the print data printed in one back-and-forth movement of the carriage 43. Further, the flushing determination section 8 calculates a hypothetical back-and-forth time, which is the time of one back-and-forth movement of the carriage required when the carriage turns around at the hypothetical turnaround position. Further, the flushing determination section 8 calculates a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer 45.

[0096] The flushing determination section 8 determines whether the hypothetical back-and-forth time exceeds the threshold value. In the case where the hypothetical back-and-forth time exceeds the threshold value, the flushing determination section 8 determines the position at which the time of one back-and-forth movement of the carriage is longer than the hypothetical back-and-forth time, that is, the position at which the time of one back-and-forth movement of the carriage is longer than the threshold value Time thresh ​The long position is set as a turnaround position in the reciprocating movement of the carriage 43, and determines the implementation of the flushing in the loop of the movement of the carriage 43.

[0097] In the present embodiment, the printing device 100 preferably performs the flushing operation in the loop in the flushing section 77b of the maintenance section 70b.

[0098] 1. Modification 1

[0099] Figure 8 is an explanatory view that explains the operation of the printing device 100 of the modification of the present embodiment. The printing device 100 is provided with a belt 23 that supports the print medium 95.

[0100] The belt 23 corresponds to one example of a support section.

[0101] The printing device 100 has a plurality of flushing sections 77 that are arranged on both sides of the support section in the first direction and receive ink at the time of flushing implementation. The flushing determination section 8 determines whether or not to implement flushing in the loop of the reciprocating movement of the carriage 43. In the case where it is determined to implement flushing in the loop of the movement of the carriage, the flushing determination section 8 determines whether to perform the flushing operation in the flushing section 77b or in the loop of the movement of the carriage in the region of the support section that does not overlap with the print medium, according to the width of the print medium 95, and sets the turnaround position based on the determination.

[0102] In the present modification 1, a case where the width of the print medium 95 is narrow and the belt 23 is not covered by the print medium 95 is indicated. At this time, in the case where it is determined to implement flushing in the loop of the movement of the carriage, the printing device 100 does not implement flushing in the loop in the flushing section 77b, and does not move the carriage 43 to the flushing section 77b if it is possible to perform flushing in the region A of the belt 23 that does not overlap with the print medium 95, and improves the productivity of printing by performing the flushing operation in the loop in the region A of the belt 23 that does not overlap with the print medium 95. Since the belt 23 is periodically cleaned by the cleaning section 51, the possibility that the print medium 95 is contaminated with excess ink adhering to the surface of the belt 23 is low.

[0103] 2. Modification 2

[0104] The print medium 95 supported by the belt 23 is moved in the second direction that is perpendicular to the first direction, specifically in the direction of the arrow B in the drawing, in the printing. Figure 2The medium is conveyed in the +X axis direction. The time for conveying the printing medium 95 is defined as the relative travel time. Furthermore, the deceleration time of the carriage 43 in the current reciprocating motion's outgoing path is called the current path outgoing deceleration time, the deceleration time of the carriage 43 in the current reciprocating motion's return path is called the current path return deceleration time, and the acceleration time of the carriage 43 in the next reciprocating motion's outgoing path is called the next path outgoing acceleration time. (The same applies in later embodiments.) When the relative travel time is longer than the sum of the current path return deceleration time and the next path outgoing acceleration time, the non-ejection time during the reciprocating motion of the carriage 43, during which the nozzle 41 does not eject ink based on the printing data, is calculated in addition to the assumed reciprocating time Time. elapse In addition, relative travel time also needs to be considered. Specifically, this involves summing the deceleration time exceeding the current path loop and the acceleration time of the next path within the relative travel time, and then subtracting this sum from the assumed round-trip time. elapse Add them together.

[0105] Specifically, assuming that the relative movement time between the print head 42 and the printing medium 95 in the second direction orthogonal to the first direction, which occurs after the print head 42 ejects droplets from the printing medium 95 during the reciprocating motion of the carriage 43, is longer than the acceleration / deceleration time, the reciprocating time Time is assumed to be... elapse The calculation is performed using the following mathematical formula (3).

[0106]

Number 3

[0107]

[0108] The flushing determination unit 8 determines the assumed round-trip time. elapse Has the threshold Time been exceeded? thresh Assuming a round-trip time of Time elapse Time exceeding the threshold thresh In the case of a location where the round-trip time is longer than the assumed round-trip time, i.e., the round-trip time is longer than the threshold Time, the location is considered to have a longer round-trip time. thresh The long position is set as the reversing position in the reciprocating motion of the carriage 43, and flushing is performed in the carriage movement loop.

[0109] Threshold Time thresh Similar to the above implementation, the calculation is performed using mathematical formula (2) based on the pre-determined correspondence between the non-ejection time (the time during which droplets are not ejected from the nozzle) and the temperature, i.e., the landing error of the droplets ejected from the nozzle is below a specified allowable value.

[0110] 3. Variation Example 3

[0111] In a case where the wait time as the standby time of the carriage 43 is set between the paths of the current path and the next path, the wait time needs to be considered as the non-ejection time. In the present embodiment, the wait time starts together with the start of deceleration of the carriage 43, but is not limited thereto. The wait time has a first wait time set between the current path outgoing route and the current path return route, and a second wait time set between the current path return route and the next path outgoing route. The substantial wait time to be considered must be added as the non-ejection time. Specifically, in a case where the relative movement time is longer than the second wait time, the round trip time Time elapse is calculated by the following mathematical expression (4).

[0112] [Num 4]

[0113]

[0114] In a case where the relative movement time is the second wait time or less, the round trip time Time elapse is calculated by the following mathematical expression (5).

[0115] [Num 5]

[0116]

[0117] The flushing determination section 8 determines whether the assumed round trip time Time elapse exceeds the threshold value Time thresh . In a case where the assumed round trip time Time elapse exceeds the threshold value Time thresh , the position where the one-way round trip movement time is longer than the assumed round trip time, that is, the position where the one-way round trip movement time is longer than the threshold value Time thresh is set as the turnaround position in the round trip movement of the carriage 43, and flushing is performed in the return route of the carriage movement.

[0118] The threshold value Time thresh , as with the above embodiment, the non-ejection time as the time during which no liquid droplet is ejected from the nozzle and the temperature are used to calculate using the mathematical expression (2) in accordance with the correspondence relationship, that is, the condition under which the landing error of the liquid droplet ejected from the nozzle is the prescribed allowable value or less.

[0119] 4. Modified example 4

[0120] In the above embodiment, the condition under which the landing error is below the allowable value at the ambient temperature T measured by the thermometer is found based on the relationship between the non-ejection distance in the prescribed movement speed of the carriage 43 and the round-trip distance in the one-time movement of the carriage 43 based on the print data. In the present modification, the condition under which the landing error is below the allowable value at the temperature T is found based on the relationship between the non-ejection distance in the prescribed movement speed of the carriage 43 and the round-trip distance in the one-time movement of the carriage 43 based on the print data.

[0121] Specifically, the printing device 100 includes the print head 42 that ejects droplets from the nozzle 41 toward the print medium 95, the carriage 43 that supports the print head 42 and performs reciprocating movement in the first direction, the thermometer 45 that measures the ambient temperature in the vicinity of the nozzle 41, the control section 1 that controls the reciprocating movement of the carriage 43 and the ejection of droplets from the nozzle 41, the purge determination section 8 that determines whether or not to perform purge in the loop of the reciprocating movement of the carriage 43, and the storage section 5 that stores the correspondence relationship between the non-ejection distance, which is the distance in which no droplet is ejected from the nozzle 41, and the temperature, which is found in advance, i.e., the condition under which the landing error of the droplet ejected from the nozzle 41 is below the prescribed allowable value. In the purge determination section 8, in the one-time reciprocating movement of the carriage 43, the assumed turnaround position in the reciprocating movement of the carriage 43 is calculated based on the print data printed in the one-time reciprocating movement, the assumed round-trip distance, which is the one-time reciprocating movement distance of the carriage 43 when the carriage 43 turns around at the assumed turnaround position, is calculated, the third threshold value, which is the longest non-ejection distance that satisfies the condition at the ambient temperature measured by the thermometer 45, is calculated, it is determined whether or not the assumed round-trip distance exceeds the third threshold value, in the case where the assumed round-trip distance exceeds the third threshold value, the position at which the one-time reciprocating movement distance is longer than the assumed round-trip distance, i.e., the position at which the one-time reciprocating movement distance is longer than the threshold value, is set as the turnaround position in the reciprocating movement of the carriage 43, and it is determined to perform purge in the loop of the carriage movement.

[0122] The printing device 100 of the embodiment of the present application includes a print head 42 that ejects droplets from a nozzle 41 toward a print medium 95, a carriage 43 that supports the print head 42 and performs reciprocating movement in a first direction, a thermometer 45 that measures the ambient temperature in the vicinity of the nozzle 41, a control section 1 that controls the reciprocating movement of the carriage 43 and the ejection of droplets from the nozzle 41, a flushing determination section 8 that determines whether flushing is performed in a loop of the reciprocating movement of the carriage 43, and a storage section 5 that stores a correspondence relationship between a non-ejection time, which is a time during which no droplets are ejected from the nozzle 41, and a temperature, which is previously calculated, and a condition under which a landing error of the droplets ejected from the nozzle 41 is equal to or less than a predetermined allowable value. In the flushing determination section 8, in one reciprocating movement of the carriage 43, a hypothetical turnaround position in the reciprocating movement of the carriage 43 is calculated on the basis of print data printed in the one reciprocating movement, a hypothetical reciprocating time, which is a time of one reciprocating movement of the carriage 43 required when the carriage 43 turns around at the hypothetical turnaround position, is calculated, a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer 45, is calculated, it is determined whether the hypothetical reciprocating time exceeds the threshold value, and in the case where the hypothetical reciprocating time exceeds the threshold value, a position at which the time of one reciprocating movement of the carriage 43 is longer than the hypothetical reciprocating time, that is, a position at which the time of one reciprocating movement of the carriage 43 is longer than the threshold value Time thresh long, is set as the turnaround position in the reciprocating movement of the carriage 43, and it is determined that flushing is performed in the loop of the movement of the carriage.

[0123] According to the printing device 100 described above, by performing flushing in the loop of the movement of the carriage, the following excellent effects are exerted: the standing time during which no ink is ejected from the nozzle 41 is shortened, clogging of the ink is prevented, and the image quality is stabilized. Furthermore, the threshold value, which is the longest non-ejection time that is optimal, is calculated on the basis of the ambient temperature in which the nozzle is located, and by comparing the threshold value with the reciprocating time of the carriage 43 predicted on the basis of the print data, the necessity of flushing in the loop is determined, and thus the number of times of flushing is suppressed to the minimum.

[0124] The printing device 100 of the embodiment of the present application includes a belt 23 that supports a print medium 95, and a plurality of flushing sections 77 that are arranged on both sides of the belt 23 in the first direction, receive ink at the time of flushing, and in the case where it is determined that flushing is performed in the loop of the movement of the carriage, the flushing determination section 8 determines whether flushing in the loop of the movement of the carriage is performed in the flushing sections 77b or in a region of the belt 23 that does not overlap the print medium 95 on the basis of the width of the print medium 95, and sets the turnaround position on the basis of the determination.

[0125] According to the printing device 100 described above, flushing can be performed not in the flushing sections 77 arranged at both ends of the belt 23 but in a position on the belt 23 that does not overlap the print medium 95, and thus the following excellent effect can be exerted: productivity can be improved.

[0126] The printing device 100 of the embodiment of the present application has, as a printing mode, a first mode in which the moving speed of the carriage 43 is a first speed, and a second mode in which the moving speed of the carriage 43 is a second speed different from the first speed, the correspondence relation has a first correspondence relation when the moving speed of the carriage 43 is the first speed, and a second correspondence relation when the moving speed of the carriage 43 is the second speed, and the flushing determination section 8 calculates the threshold value using the first correspondence relation as the correspondence relation when the printing mode is the first mode, and calculates the threshold value using the second correspondence relation as the correspondence relation when the printing mode is the second mode.

[0127] According to the above-described printing device 100, the non-ejection time, which is the time during which no droplet is ejected from the nozzle 41, and the temperature are applied in correspondence with each other in a range in which the landing error becomes a predetermined allowable value, according to the moving speed of the carriage, and thus an excellent effect that proper flushing operation can be performed is exerted.

[0128] The printing device 100 of the embodiment of the present application defines the moving speed of the carriage 43 when printing at a fixed speed as a CR speed, defines the distance in which the carriage 43 moves in one pass as a path width, defines the value obtained by adding the distances in which the moving speed of the carriage 43 is accelerated or decelerated in one pass as an acceleration / deceleration printing width, and defines the value obtained by adding the times in which the carriage 43 is accelerated or decelerated in one pass as an acceleration / deceleration time, and when Time elapse is the following mathematical expression (1).

[0129] [Num 6]

[0130]

[0131] Temp ref0 and Temp ref1 corresponding to the non-ejection time are defined as Time ref0 and Time ref1 respectively, and when Time thresh is the following mathematical expression (2).

[0132] [Num 7]

[0133]

[0134] According to the above-described printing device 100, Time threshThe one-way time of the carriage 43 (the maximum non-ejection time), thus, has an excellent effect of enabling proper flushing operations.

[0135] The printing device 100 of the embodiment of the present application has an excellent effect of enabling proper flushing operations in the case where the relative movement time of the print head 42 with respect to the print medium 95 in the second direction orthogonal to the first direction is longer than the acceleration / deceleration time in the case where the wait time is set between the paths. elapse is the following mathematical expression (3).

[0136]

Number 8

[0137]

[0138] According to the above-described printing device 100, in the case where the print medium 95 is relatively moved in the second direction orthogonal to the first direction, even in the case where the relative movement is performed for a longer time than the acceleration / deceleration time of the carriage 43, an excellent effect of enabling calculation of the proper frequency of flushing operations is exerted.

[0139] The printing device 100 of the embodiment of the present application has an excellent effect of enabling proper flushing operations in the case where the relative movement time is longer than the second wait time in the case where the wait time is set between the paths, the wait time set between the current path outbound and the current path return is set as the first wait time, and the wait time set between the current path return and the next path outbound is set as the second wait time. elapse is the following mathematical expression (9).

[0140]

Number 9

[0141]

[0142] Further, in the case where the relative movement time is the second wait time or less, Time elapse is the following mathematical expression (5).

[0143]

Number 10

[0144]

[0145] According to the above-described printing device 100, even in the case where the wait time is set between the paths, an excellent effect of enabling calculation of the proper frequency of flushing operations is exerted.

[0146] The printing device 100 of the embodiment of the present application includes a print head 42 that ejects droplets from a nozzle 41 toward a print medium 95; a carriage 43 that supports the print head 42 and performs reciprocating movement in a first direction; a thermometer 45 that measures the ambient temperature in the vicinity of the nozzle 41; a control section that controls the reciprocating movement of the carriage 43 and the ejection of droplets from the nozzle 41; a flushing determination section 8 that determines whether flushing is performed in a loop of the reciprocating movement of the carriage 43; and a storage section that stores a correspondence relationship between a non-ejection distance, which is a distance in which no droplets are ejected from the nozzle 41, and a temperature, which is calculated in advance, and a condition in which a landing error of the droplets ejected from the nozzle 41 is below a prescribed allowable value. In the flushing determination section 8, a hypothetical turnaround position in the reciprocating movement of the carriage 43 is calculated on the basis of print data printed in one reciprocating movement of the carriage 43. A hypothetical reciprocating distance, which is a one-way reciprocating movement distance of the carriage 43 when the carriage 43 turns around at the hypothetical turnaround position, is calculated. A third threshold value, which is the longest non-ejection distance that satisfies the condition at the ambient temperature measured by the thermometer 45, is calculated. It is determined whether the hypothetical reciprocating distance exceeds the third threshold value. In the case where the hypothetical reciprocating distance exceeds the third threshold value, a position at which the one-way reciprocating movement distance is longer than the hypothetical reciprocating distance, that is, a position at which the one-way reciprocating movement distance is longer than the third threshold value, is set as the turnaround position in the reciprocating movement of the carriage 43, and it is determined that flushing is performed in the loop of the carriage movement.

[0147] According to the printing device 100 described above, the optimal flushing frequency can be calculated on the basis of the reciprocating movement distance of the carriage 43 assumed on the basis of the print data and the third threshold value, which is the longest non-ejection distance at the ambient temperature in the vicinity of the nozzle 41, and thus the effect of stabilizing the image quality is exerted.

[0148] The printing control method of the embodiment of the present application is in a printing device 100 that has a print head 42 that ejects droplets from a nozzle 41 toward a print medium 95, a carriage 43 that supports the print head 42 and performs reciprocating movement in a first direction, a thermometer 45 that measures the ambient temperature in the vicinity of the nozzle 41, and a control section 1 that controls the reciprocating movement of the carriage 43 and the ejection of droplets from the nozzle 41, in which, in the printing control method, it is determined whether or not purging is performed in a loop of the reciprocating movement of the carriage 43, a correspondence relation between a non-ejection time, which is a time during which no droplets are ejected from the nozzle 41, and a temperature, which is previously calculated, is stored as a condition under which the landing error of the droplets ejected from the nozzle 41 is below a prescribed allowable value, in the determination, in one reciprocating movement of the carriage 43, a hypothetical turnaround position in the reciprocating movement of the carriage 43 is calculated based on print data that is printed in the one reciprocating movement, a hypothetical reciprocating time, which is the time of one reciprocating movement of the carriage 43 required when the carriage 43 turns around at the hypothetical turnaround position, is calculated, a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer 45, is calculated, it is further determined whether or not the hypothetical reciprocating time exceeds the threshold value, in the case where the hypothetical reciprocating time exceeds the threshold value, the position at which the time of one reciprocating movement of the carriage 43 is longer than the hypothetical reciprocating time, i.e., the position at which the time of one reciprocating movement of the carriage 43 is longer than the threshold value Time thresh is set as the turnaround position in the reciprocating movement of the carriage 43, and it is determined that purging is performed in the loop of the movement of the carriage.

[0149] According to the above-described printing device 100, by performing purging in the loop of the movement of the carriage, the following excellent effects are exerted: the standing time during which no ink is ejected from the nozzle 41 is shortened, clogging of the ink is prevented, and the image quality is stabilized. Furthermore, the threshold value, which is the longest non-ejection time that is the best, is calculated according to the ambient temperature in which the nozzle is located, the necessity of purging in the loop is determined by comparing the threshold value with the reciprocating time of the carriage 43 predicted from the print data, and thus the number of times of purging is suppressed to the minimum.

[0150] The above-described embodiment merely represents one mode of the present application, and can be arbitrarily modified and applied within the scope of the present application.

[0151] For example, in the above-described embodiment, a printer is exemplified as the printing device, but the printing device of the present application is not limited to a printer, and for example, can be a multifunction peripheral that has a scanning function, a facsimile function, or the like.

[0152] For example, the functions of the control section 1 can also be realized by a plurality of processors or semiconductor chips.

[0153] For example, Figure 1The illustrated parts are an example, and the specific installation method is not particularly limited. That is, it is not necessary to install hardware corresponding to each part individually, and it is of course possible to configure so that a processor executes a program to implement the functions of each part. Furthermore, in the above-described embodiments, a part of the functions implemented by software can be implemented as hardware, or a part of the functions implemented by hardware can be implemented by software. Furthermore, the specific details of the configuration of the printing device 100 and the other parts of the control section 1 can be arbitrarily changed within a range that does not depart from the gist of the present application.

[0154] For example, Figure 7 The step units of the illustrated actions are step units divided for easy understanding of the actions of the parts of the printing device 100 according to the main processing contents, and the present application is not limited by the method of division of the processing units, the names. It is possible to divide into more step units according to the processing contents. Furthermore, it is also possible to divide so that more processing is included in one step unit. Furthermore, the order of the steps can be appropriately changed within a range that does not affect the gist of the present application.

Claims

1. A printing device characterized by comprising: Possessing: an inkjet recording head that ejects liquid droplets from a nozzle toward a print medium; a carriage that supports the recording head and performs reciprocating movement in a first direction; a thermometer that measures an ambient temperature in the vicinity of the nozzle; a control section that controls the reciprocating movement of the carriage and the ejection of the liquid droplets from the nozzle; a flushing determination section that determines whether flushing is implemented in a loop of the reciprocating movement of the carriage; and a storage section that stores a correspondence relationship between a non-ejection time, which is a time during which the liquid droplets are not ejected from the nozzle, and a temperature, which is a condition under which a landing error of the liquid droplets ejected from the nozzle is below a prescribed allowable value, which is obtained in advance, in the flushing determination section, in one reciprocating movement of the carriage, based on print data printed in the one reciprocating movement, a hypothetical turnaround position in the reciprocating movement of the carriage is calculated, a hypothetical turnaround time, which is a time of the one reciprocating movement of the carriage required when the carriage turns around at the hypothetical turnaround position, is calculated, a threshold value, which is the longest non-ejection time that satisfies the condition at the ambient temperature measured by the thermometer, is calculated, it is determined whether the hypothetical turnaround time exceeds the threshold value, in the case where the hypothetical turnaround time exceeds the threshold value, a position at which the time of the one reciprocating movement is longer than the hypothetical turnaround time is set as a turnaround position in the reciprocating movement of the carriage, and it is determined that flushing is implemented in a loop of the reciprocating movement of the carriage.

2. The printing apparatus of claim 1, wherein Possessing: a support section that supports the print medium; and a plurality of flushing sections that are arranged on both sides of the support section in the first direction and that receive ink when flushing is implemented, in the case where it is determined that flushing is implemented in a loop of the reciprocating movement of the carriage, the flushing determination section determines whether flushing in a loop of the reciprocating movement of the carriage is performed in the flushing sections or in a region of the support section that does not overlap with the print medium, according to the width of the print medium, the turnaround position is set based on the determination.

3. The printing device according to claim 1 or 2, characterized in that as a print mode, a first mode in which the moving speed of the carriage is a first speed and a second mode in which the moving speed of the carriage is a second speed different from the first speed are possessed, the correspondence relationship has a first correspondence relationship when the moving speed of the carriage is the first speed and a second correspondence relationship when the moving speed of the carriage is the second speed, the flushing determination section calculates the threshold value using the first correspondence relationship as the correspondence relationship when the print mode is the first mode, and calculates the threshold value using the second correspondence relationship as the correspondence relationship when the print mode is the second mode.

4. The printing device according to claim 1, characterized in that when a moving speed of the carriage at the time of printing at a constant speed is defined as a CR speed, a distance of a round trip movement of the carriage in one pass is defined as a path width, a value obtained by adding distances of acceleration and deceleration of the carriage in one pass is defined as an acceleration and deceleration printing width, and a value obtained by adding times of acceleration and deceleration of the carriage in one pass is defined as an acceleration and deceleration time, Time representing the assumed round trip time elapse is the following mathematical expression (1), When Temp ref0 and Temp ref1 corresponding to the threshold values are defined as Time ref0 and Time ref1 respectively, Time thresh indicating the threshold value in T as the ambient temperature is the following mathematical expression (2), 5. The printing device according to claim 4, wherein In a case where the time of relative movement of the recording head with respect to the print medium in a second direction orthogonal to the first direction, which is implemented after the ejection of the liquid droplets from the recording head toward the print medium in conjunction with the reciprocating movement of the carriage, is longer than the acceleration / deceleration time, the Time elapse is the following mathematical expression (3), 6. The printing device according to claim 5, wherein when a waiting time is provided between paths, the waiting time provided between a current path pass and a current path return is defined as a first waiting time, and the waiting time provided between the current path return and a next path pass is defined as a second waiting time, when the relative movement time is longer than the second waiting time, The Time elapse is the following mathematical expression (4), and when the relative movement time is the second waiting time or less, The Time elapse is the following mathematical expression (5), 7. A printing device characterized by comprising: comprises: an inkjet recording head that ejects a liquid droplet from a nozzle toward a print medium; a carriage that supports the recording head and performs a round trip movement in a first direction; a thermometer that measures an ambient temperature in the vicinity of the nozzle; a control section that controls the round trip movement of the carriage and the ejection of the liquid droplet from the nozzle; a flushing determination section that determines whether or not flushing is performed in a return of the round trip movement of the carriage; and a storage section that stores a correspondence relationship between a non-ejection distance, which is a distance in which the liquid droplet is not ejected from the nozzle, and a temperature, i.e., a condition in which a landing error of the liquid droplet ejected from the nozzle is a prescribed allowable value or less, in the flushing determination section, in one round trip movement of the carriage, based on print data printed in the one round trip movement, a hypothetical turnaround position in the round trip movement of the carriage is calculated, a hypothetical round trip distance, which is a distance of the one round trip movement of the carriage required when the carriage turns around at the hypothetical turnaround position, is calculated, a third threshold value, which is a longest non-ejection distance that satisfies the condition at the ambient temperature measured by the thermometer, is calculated, it is determined whether or not the hypothetical round trip distance exceeds the third threshold value, in a case where the hypothetical round trip distance exceeds the third threshold value, a position at which the distance of the one round trip movement is longer than the hypothetical round trip distance is set as a turnaround position in the round trip movement of the carriage, and it is determined that flushing is performed in the return of the round trip movement of the carriage.

8. A printing control method characterized by comprising: a printing device that comprises: an inkjet recording head that ejects a liquid droplet from a nozzle toward a print medium; a carriage that supports the recording head and performs a round trip movement in a first direction; a thermometer that measures an ambient temperature in the vicinity of the nozzle; and a control section that controls the round trip movement of the carriage and the ejection of the liquid droplet from the nozzle, in the printing control method, it is determined whether or not flushing is performed in a return of the round trip movement of the carriage, ​ stores a correspondence relation between a non-ejection time, which is a time when the liquid droplet is not ejected from the nozzle, and a temperature, which is previously calculated, as a condition under which a landing error of the liquid droplet ejected from the nozzle is equal to or less than a prescribed allowable value, in the determination, in one round trip of the carriage, based on print data printed in the one round trip, a hypothetical turnaround position in the round trip of the carriage is calculated, a hypothetical round trip time, which is a time of the one round trip of the carriage required when the carriage turns around at the hypothetical turnaround position, is calculated, and a threshold value, which is a longest non-ejection time satisfying the condition at the environmental temperature measured by the thermometer, is calculated, it is also determined whether the hypothetical round trip time exceeds the threshold value, in a case where the hypothetical round trip time exceeds the threshold value, a position at which the time of the one round trip is longer than the hypothetical round trip time is set as a turnaround position in the round trip of the carriage, and it is determined that purging is implemented in a loop of the round trip of the carriage.

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