JP2022152179A - printer - Google Patents

Abstract

To provide a printer capable of restraining degradation of a printing image quality resulting from the shape of printing media.SOLUTION: A printer 10 comprises: a head 20 discharging a liquid to a printing medium A; a light irradiation part 30 irradiating the liquid on the printing medium with light; a relative displacement unit 40 relatively moving the printing medium A, the head and the light irradiation part in a movement direction along which the head and the light irradiation part line up; and a controller 60. The controller controls the relative displacement unit so that the relative displacement speed of the printing medium A and the light irradiation part is slower when the gap of the light irradiation part to the printing medium is a first gap compared to the case where the gap is a second gap smaller than the first gap.SELECTED DRAWING: Figure 4

Description

The present invention relates to printing devices.

2. Description of the Related Art Conventionally, as a printing apparatus, a printing apparatus disclosed in Patent Document 1 is known. This printing apparatus includes a head capable of ejecting liquid onto a recording medium, and a light emitting element capable of irradiating the liquid ejected onto the print medium with light.

JP 2015-58670 A

In the printing apparatus disclosed in Patent Document 1, an image is printed on a print medium by ejecting liquid from the head and making it land on the print medium, and then irradiating the print medium with light from the light emitting element to fix the liquid on the print medium. ing. In such a printing apparatus, for example, when the print medium has a three-dimensional shape, the distance between the light emitting element and the print medium changes according to the unevenness of the print medium. The time until the liquid is irradiated changes. As a result, the appearance of the liquid cured by light becomes non-uniform, which may lead to deterioration in image quality.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a printing apparatus capable of suppressing deterioration in print image quality due to the shape of a print medium.

A printing apparatus according to an aspect of the present invention includes a head that ejects liquid onto a print medium, a light irradiation unit that irradiates light onto the liquid on the print medium, and a moving direction in which the head and the light irradiation unit are aligned. a relative movement device that relatively moves the print medium, the head, and the light irradiation unit; When the gap is a second gap smaller than the first gap, the relative movement device is controlled such that the relative movement speed between the print medium and the light irradiation unit is slower.

ADVANTAGE OF THE INVENTION This invention is effective in the ability to provide the printing apparatus which can suppress the deterioration of the printing image quality resulting from the shape of a printing medium.

The above objects, other objects, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments with reference to the accompanying drawings.

1 is a perspective view of a printing device; FIG. 2 is a functional block diagram showing the configuration of the printing apparatus of FIG. 1; FIG. FIG. 2 is a schematic view of the head unit of FIG. 1 viewed from below; 2 is a schematic view of the head unit and stage of FIG. 1 as viewed from the front; FIG. FIG. 5(a) is a graph showing changes over time in the illuminance of light in the second gap region. FIG. 5(b) is a graph showing changes over time in the illuminance of light in the first gap region. FIG. 6A is a schematic front view of a head unit and a printing medium having unevenness. FIG. 6B is a schematic front view of the head unit and the slanted print medium.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the following description, the same reference numerals are given to the same or corresponding elements throughout all the drawings, and duplicate descriptions thereof will be omitted.

(Embodiment)
<Configuration of printing device>
For example, as shown in FIG. 1, the printing apparatus 10 according to the embodiment of the present invention ejects liquid from the head 20 onto the print medium A, irradiates the print medium A with light from the light irradiation unit 30, and produces an image. is an inkjet printer that prints Examples of the print medium A include sheets such as cloth and paper, and three-dimensional objects such as balls and mugs. The liquid is a photocurable liquid, such as ink that is cured by light such as ultraviolet light or infrared light. Further, for example, the printing apparatus 10 may be a 3D printer, and may create a modeled object formed with ink ejected from the head 20 and cured with light emitted from the light irradiation unit 30 . In this case, the printing medium A is the modeled object being created. Further, the printing apparatus 10 may eject ink from the head 20 onto the created modeled object and irradiate the ink with light from the light irradiation unit 30 to print an image on the modeled object. In this case, the print medium A is the created modeled object.

The printing apparatus 10 includes a head unit 11, a relative movement device 40, a conveying device 50, a tank 12 and a control device 60 (FIG. 2). Details of the control device 60 will be described later. Further, the movement direction in which the head 20 and the light irradiation unit 30 are arranged is called the left-right direction, and the transport direction that intersects (for example, orthogonally) the movement direction is called the front-rear direction, and intersects (for example, orthogonally) the left-right direction and the front-rear direction. The direction is called the vertical direction. However, the layout of the printing device 10 is not limited to this.

The relative movement device 40 has a pair of movement rails 41, a carriage 42, a drive belt 43, and a movement motor 44, and moves the head unit 11 in the horizontal direction. The pair of moving rails 41 are long members extending in the left-right direction, and are arranged parallel to each other so as to sandwich the head unit 11 therebetween in the front-rear direction. The carriage 42 carries the head unit 11 and is supported so as to be movable in the left-right direction along the movement rails 41 . The drive belt 43 is an endless belt, extends laterally along the movement rail 41, is connected to the carriage 42, and is connected to the movement motor 44 via a pulley. The movement motor 44 drives the drive belt 43 to reciprocate the carriage 42 along the movement rail 41 in the horizontal direction. Thereby, the relative movement device 40 relatively moves the print medium A, the head 20 and the light irradiation section 30 in the horizontal direction.

The transport device 50 has a stage 51, transport rails 52, a stage support table 53, and a transport motor 54 (FIG. 2). The print medium A is placed on the upper surface of the stage 51 , supports the print medium A, and defines a gap between the print medium A and the head 20 in the vertical direction. The transport rail 52 extends in the front-rear direction. The stage support table 53 , for example, supports the stage 51 , is supported so as to be movable in the front-rear direction along the transport rails 52 , and is connected to the transport motor 54 . The transport motor 54 drives the stage support 53 to move the stage 51 forward and backward.

The head unit 11 includes a head 20 and a light irradiation section 30 , which are arranged such that their lower surfaces face the upper surface of the stage 51 . The tank 12 is a container that stores liquid, and is connected to the head 20 by a tube or the like to supply the liquid.

<Head unit configuration>
As shown in FIGS. 3 and 4, the head 20 has a plurality of nozzles 21, liquid channels, channel forming bodies 24, and a plurality of drive elements 25 (FIG. 2). The plurality of nozzles 21 form a nozzle row 26 arranged at equal intervals in the front-rear direction. The plurality of nozzle rows 26 are arranged at equal intervals in the left-right direction.

The channel forming body 24 has, for example, a rectangular parallelepiped shape, and the nozzle 21 and the liquid channel are formed therein. The nozzle 21 opens at the lower surface of the flow path forming body 24 . The liquid flow path is connected to tank 12 (FIG. 1) and nozzle 21 and has a common flow path 23 and a plurality of individual flow paths 22 . The common flow path 23 extends in the front-rear direction, and a plurality of individual flow paths 22 branch off from the common flow path 23 . The individual channels 22 are connected at their upstream ends to the common channel 23 and at their downstream ends to the nozzles 21 . Therefore, the liquid flows from the tank 12 to the common flow path 23 , is divided into the individual flow paths 22 while flowing in the common flow path 23 in the front-rear direction, and is supplied to the nozzles 21 .

The driving element 25 is a piezoelectric element, a heating element, an electrostatic actuator, or the like, and is provided corresponding to the individual channel 22 and drives the individual channel 22 so as to vary the volume thereof. As a result, the liquid in the individual flow paths 22 is applied with pressure for ejecting the liquid from the nozzles 21 .

The light irradiation unit 30 is arranged upstream of the head 20 in the direction in which the head 20 moves while ejecting liquid. In unidirectional printing, for example, liquid is ejected when the head 20 moves to the left, and liquid is not ejected when it moves to the right. In this case, the light irradiation unit 30 is arranged on the right side, which is upstream of the head 20, in the direction of movement to the left during printing. The light irradiation unit 30 irradiates the liquid on the print medium A with light while moving following the head 20 that ejects the liquid onto the print medium A. As shown in FIG.

In bi-directional printing, the printer 10 has a pair of light irradiation units 30 arranged so as to sandwich the head 20 in the left-right direction. Of the pair of light irradiation units 30, the right light irradiation unit 30 follows the head 20 that ejects the liquid onto the print medium A while moving leftward, and moves leftward to irradiate the liquid on the print medium A. Irradiate with light. In addition, the left light irradiation unit 30 of the pair of light irradiation units 30 moves rightward following the head 20 that ejects the liquid onto the print medium A while moving rightward. Shine light on the liquid.

The light irradiation section 30 has a plurality of light sources 31 and a circuit board 32 on which the light sources 31 are mounted. The circuit board 32 is made of, for example, an insulating material, has a rectangular flat plate shape, and has a lower surface on which the light source 31 is mounted. The light source 31 is, for example, a light-emitting element such as an LED, and is driven by the control device 60 to emit light (eg, ultraviolet light or infrared light) for curing the liquid ejected from the nozzle 21 .

The intensity of the light emitted by the light source 31 is the radiant flux emitted from the unit area of the light source 31 per unit time, and is, for example, the radiant emittance (mW/cm ² ). On the other hand, the illuminance of the light on the print medium A irradiated from the light source 31 was the radiant flux per unit area of the print medium A of the light incident from the light source 31 per unit time. /cm ² ). The illuminance may be an integrated amount of light obtained by multiplying the irradiance (mW/cm ² ) and the light irradiation time (s). The integrated amount of light is the light energy (mJ/cm ² ) per unit area on the print medium A of the light irradiated from the light irradiation section 30 .

The plurality of light sources 31 are arranged in the front-rear direction to form a light source row 33 . A plurality of (for example, seven) light source rows 33 are arranged at intervals in the left-right direction. Each light source 31 irradiates the print medium A with light of equal intensity.

<Configuration of control device>
The control device 60 is connected to the driving element 25 via a head driving circuit 63 and controls driving of the driving element 25, as shown in FIG. The control device 60 is connected to the light source 31 via a light source drive circuit 64 and controls driving of the light source 31 . The control device 60 is connected to the movement motor 44 via a movement drive circuit 65 and controls driving of the movement motor 44 . The controller 60 is connected to the transport motor 54 via a transport drive circuit 66 and controls driving of the transport motor 54 . Thereby, the control device 60 controls the driving, stopping, rotation speed, etc. of the moving motor 44 and the conveying motor 54 . Thereby, the relative movement speed between the stage 51 and the print medium A placed thereon and the head unit 11 is controlled.

The control device 60 is connected to an external power supply B such as a commercial power supply via a power supply circuit 67 . The power supply circuit 67 generates an output voltage from the DC voltage from the external power supply B, and supplies power to each part of the printing apparatus 10, such as the driving element 25, the light source 31, the moving motor 44, the conveying motor 54, and the like.

The control device 60 has a calculation section 61 and a storage section 62 . The storage unit 62 is a memory that can be accessed by the calculation unit 61, and is composed of a RAM, a ROM, and the like. The RAM temporarily stores various data such as print data. The ROM stores programs for performing various data processing. The control device 60 may be a single control device 60 for centralized control, or may be a plurality of control devices 60 for distributed control. Also, the program may be stored in a storage medium other than the storage unit 62 . Furthermore, the program may be stored in a single storage medium, or may be divided and stored in a plurality of storage media.

The computing unit 61 is composed of a processor such as a CPU, an integrated circuit such as an ASIC, and the like. The calculation unit 61 executes a program stored in the ROM to control the driving element 25, the light source 31, the moving motor 44 and the transport motor 54, and executes printing processing.

<Print processing>
In such a printing apparatus 10, the control device 60 acquires print data and executes print processing based on the print data. The print data includes image data representing an image to be printed on the print medium A (eg, raster data). The print data may be stored in the storage unit 62, or may be obtained from an external device such as a network, computer, or storage medium.

The control device 60 controls the movement motor 44 to move the head unit 11 in the horizontal direction. Further, the control device 60 controls the drive element 25 to perform an ejection operation for ejecting liquid from the head 20 . Furthermore, the control device 60 controls the light source 31 to perform a light irradiation operation of causing the light source 31 to emit light. Further, the control device 60 controls the transport motor 54 to perform a transport operation for transporting the print medium A forward. Then, the printing apparatus 10 alternately repeats the scanning operation including the moving operation, the ejection operation, and the light irradiation operation, and the conveying operation to proceed with the printing process.

In this scanning, as shown in FIG. 4, the liquid is ejected from the head 20 while moving to the left. As a result, the liquid lands on the print medium A on the stage 51 facing the lower surface of the head 20 . In addition, while the light irradiation unit 30 follows the head 20 and moves to the left, light is emitted from the light source 31 . As a result, the liquid on the print medium A facing the light source 31 is irradiated with light, and the liquid is cured by the light and fixed to the print medium A. FIG. Therefore, an image is printed on the printing medium A by the liquid.

In the example of FIG. 4, the print medium A has different gaps from the light irradiation section 30 in the left-right direction, and the gaps include a first gap greater than or equal to a predetermined value G1 and a second gap less than the predetermined value G1. there is Therefore, the print medium A has a first gap area A1, which is the area of the first gap, and a second gap area A2, which is the area of the second gap.

In this case, light having an illuminance shown in FIG. 5A is irradiated from the light irradiation section 30 to the second gap region A2. Further, light having an illuminance shown in FIG. 5B is irradiated from the light irradiation section 30 to the first gap region A1. As described above, when the light irradiation unit 30 irradiates light downward toward the print medium A, the light spreads in the direction perpendicular to the vertical direction as it moves away from the light irradiation unit 30 downward. The illuminance (mW/cm ² ) of the light on the print medium A increases toward the center of the light irradiation section 30 in the direction perpendicular to the vertical direction, and decreases away from the center. A light irradiation range is defined as a range where the illuminance on the print medium A is equal to or higher than a predetermined curing illuminance. The predetermined curing illuminance is, for example, the illuminance I0 for curing the liquid on the print medium A. FIG.

This curing includes main curing and temporary curing. Temporary curing is a state in which the viscosity of the liquid is higher than that of the uncured liquid immediately after landing, but the liquid is not completely cured, and the viscosity of the liquid has increased to a viscosity that does not flow on the print medium A. Specifically, the liquid is gel-like. Full curing is a state in which the liquid is completely cured, and more specifically, it is a state in which even if the liquid is touched with a hand, the liquid does not stick to the hand.

The irradiation range of light from the light irradiation unit 30 in the first gap region A1 shown in FIG. 5B is greater than the irradiation range of light from the light irradiation unit 30 in the second gap region A2 shown in FIG. becomes wider. Therefore, for example, if the liquid J lands on the first gap area A1 and is cured by light before it spreads on the print medium A, the appearance of the cured product becomes matte. On the other hand, for example, when the liquid J lands on the second gap region A2, spreads on the print medium A, and is then cured by light, the appearance of the cured product becomes glossy.

Thus, if the curing time of the liquid J differs according to the gap, the appearance of the cured product becomes nonuniform, resulting in deterioration of print image quality. On the other hand, in the printing apparatus 10, when the gap of the light irradiation unit 30 with respect to the printing medium A is the first gap, compared with the case of the second gap, which is smaller than the first gap, the control device 60 The relative movement device 40 is controlled so that the relative movement speed between the stage 51 and the light irradiation section 30 becomes slow. As a result, it is possible to reduce the curing time difference until the liquid J that has landed on the print medium A is cured, thereby reducing deterioration in image quality.

Specifically, the control device 60 divides the print data into scan print data for each scan. Further, the control device 60 acquires gap information indicating the gap between the print medium A and the light irradiation unit 30, for example, based on measurement by a sensor provided in the printing apparatus 10 or specifications indicating the shape of the print medium A. obtain. Then, the control device 60 moves the head unit 11 to the left side by the moving operation, ejects the liquid J from the head 20 onto the printing medium A based on the scanning print data by the ejecting operation, and performs the light irradiation operation to eject the liquid J onto the printing medium A. The liquid J on A is irradiated with light from the light irradiation unit 30 . In this moving operation, the control device 60 switches the moving speed of the light irradiation section 30 of the head unit 11 between the first speed and the second speed based on the gap information.

As a result, in the second gap region A2 in FIG. 5A, the illuminance of the light from the light irradiation unit 30 reaches the predetermined curing illuminance I0 at time ta0 after the liquid J material lands from the head 20 at time t0. , the liquid J is cured in the second curing time Ta0 during this period. In the first gap region A1 in FIG. 5B, the illuminance of light reaches a predetermined curing illuminance I0 at time tb0 after the liquid J lands at time t0. hardens.

Although the light irradiation range of the first light irradiation section 30a in the first gap region is wider than the light irradiation range of the second light irradiation section 30b in the second gap region, the moving speed of the light irradiation section 30 in the first gap region A1 is is slower than the moving speed of the light irradiation section 30 in the second gap region A2. As a result, the first curing time Tb0 is made equal to or close to the second curing time Ta0, the nonuniform appearance of the cured product of the liquid J is reduced, and deterioration in print quality due to the shape of the printing medium A is suppressed. can be done.

<Modification 1>
In the printing apparatus 10 according to Modification 1, in the above-described embodiment, the control device 60 performs a movement operation for moving the head 20 and the light irradiation unit 30 by the relative movement device 40, an ejection operation for ejecting liquid from the head 20, and When printing is performed while alternately repeating scanning including a light irradiation operation for irradiating light from the light irradiation unit 30 and a transport operation for transporting the printing medium A by the transport device 50, the head 20 and the light irradiation unit 30 are arranged in the second direction. A first light irradiation operation of irradiating a first gap region of the printing medium A whose gap is the first gap while moving at one speed, and moving the head 20 and the light irradiation unit 30 faster than the first speed. While moving at the second speed, the second light irradiation operation of irradiating the second gap region of the print medium A whose gap is the second gap is performed in one scan, or the scan is the second light irradiation. A first scan including a first light irradiation operation without including a motion, and a second scan including a second light irradiation operation without including the first light irradiation operation, and conveying the first scan and the second scan It is performed separately between an operation and a transport operation that follows the transport operation.

Specifically, in one scan, the control device 60 causes the head unit 11 to move to the left by a movement operation, and causes the head 20 to eject the liquid J onto the printing medium A based on the scanning print data by an ejection operation. At the same time, the liquid J on the printing medium A is irradiated with light from the light irradiation unit 30 by the light irradiation operation. Here, the control device 60 switches the moving speed of the light irradiation section 30 of the head unit 11 between the first speed and the second speed based on the gap information. That is, the control device 60 moves the light irradiation section 30 at a first speed in the first gap, and moves the light irradiation section 30 at a second speed faster than the first speed in the second gap.

The light irradiation range of the light irradiation unit 30 on the printing medium A by the light irradiation operation of this scanning is wider in the first gap area than in the second gap area. On the other hand, the first speed of the light irradiator 30 that irradiates the light on the first gap region is lower than the second speed of the light irradiator 30 that irradiates the light on the second gap region. For this reason, the movement speed of the light irradiation range in the first gap region becomes slower than the movement speed of the light irradiation range in the second gap region. Therefore, the first curing time Tb0 of the liquid J by the light irradiation unit 30 in the first gap region matches or approaches the second curing time Ta0 of the liquid J by the light irradiation unit 30 in the second gap region, and the cured product of the liquid J It is possible to reduce the non-uniformity of the appearance of the print medium A and suppress the deterioration of the print image quality due to the shape of the print medium A.

Note that the first light irradiation operation and the second light irradiation operation may be performed by separate scanning. In this case, the control device 60 divides the print data into scan print data for each scan, and further divides the scan print data into the first gap print data and the second gap print data based on the gap information. do. In addition, although the case where the second scan is performed after the first scan is described below, the first scan may be performed after the second scan.

Then, the control device 60 executes the first scan, moves the head unit 11 at the first speed, executes the ejection operation in the first gap based on the first gap print data, Execute irradiation operation. In this ejection operation, the control device 60 causes the head 20 to eject the liquid J from the head 20 to the first gap area A1 of the print medium A without ejecting the liquid from the head 20 to the second gap area A2. Further, in the first light irradiation operation, the control device 60 irradiates light from the light irradiation section 30 to the first gap region A1. As a result, the illuminance of the light in the first gap region A1 reaches the curing illuminance I0 of the liquid J in the first curing time Tb0, the liquid J on the first gap region A1 is cured, and the printing medium A is printed.

After that, the control device 60 moves the head unit 11 to the right side without performing the transport operation, and then performs the second scanning. In the second scan, the control device 60 moves the head unit 11 to the left at the second speed in the printing range of the first scan, and executes the ejection operation in the second gap based on the second gap print data. At the same time, the second light irradiation operation is performed. In this ejection operation, the control device 60 causes the head 20 to eject the liquid J onto the second gap area A2 of the print medium A without ejecting the liquid from the head 20 onto the first gap area A1. Also, in the second light irradiation operation, the control device 60 irradiates the second gap region A2 with light. As a result, the illuminance of the light in the second gap area A2 reaches the curing illuminance I0 of the liquid J in the second curing time, the liquid J in the second gap area A2 is cured, and the printing medium A is printed.

The first scan and the second scan are performed between the transport operation and the subsequent transport operation. The first speed of the light irradiation section 30 in the first light irradiation operation of the first scan is made slower than the second speed of the light irradiation section 30 in the second light irradiation operation of the second scan. As a result, the movement of the light irradiation range by the light irradiation unit 30 is slower in the first gap than in the second gap, and the first curing time of the liquid J can be matched or brought closer to the second curing time. Therefore, it is possible to reduce non-uniformity in the appearance of the cured product of the liquid J, and to suppress deterioration in print image quality due to the shape of the print medium A.

<Modification 2>
In the printing apparatus 10 according to Modification 2, in Modification 1, when the gap satisfies a predetermined condition, the control device 60 performs the first light irradiation operation and the second light irradiation operation in one scan, and the gap is If the predetermined conditions are not met, the first scan and the second scan are performed separately.

Specifically, as shown in FIG. 6A, the control device 60 acquires the length L1 of the first gap area A1 and the length L2 of the second gap area A2 in the horizontal direction based on the gap information. . When the print medium A has a small or no inclination or little or no steps, and both the length L1 and the length L2 are equal to or greater than a predetermined length, the speed of the light irradiation unit 30 is switched in each scan. little or no In this case, the control device 60 performs the first light irradiation operation and the second light irradiation operation by changing the moving speed of the light irradiation unit 30 in one scan, assuming that a predetermined condition is satisfied.

On the other hand, when the print medium A is provided with a large inclination or many steps, and at least one of the length L1 and the length L2 is less than a predetermined length, the speed of the light irradiation unit 30 during scanning is must be switched in a short period of time. In this case, the control device 60 performs the first scan and the second scan separately on the assumption that the predetermined condition is not satisfied. Thereby, the control device 60 moves the light irradiation section 30 at the first speed in the first light irradiation operation of the first scan, and moves the light irradiation section 30 at the second speed in the second light irradiation operation of the second scan. Let As a result, the printing medium A is printed in accordance with the shape of the printing medium A without changing the moving speed of the light irradiation unit 30 in one scan, thereby improving the print quality due to the shape of the printing medium A. Decrease can be suppressed.

<Modification 3>
In the printing apparatus 10 according to Modification 3, in Modification 2, when the gap change rate in the movement direction is less than the predetermined rate, the gap satisfies the predetermined condition, and when the gap change rate is equal to or greater than the predetermined rate. , the gap does not satisfy the predetermined condition.

Specifically, as shown in FIG. 6(b), a plurality of thresholds for the gap between the print medium A and the light irradiation unit 30 (for example, the first predetermined value G1, which is the above-described predetermined value G1, and the second It has a second predetermined value G2) which is smaller than one predetermined value G1. In this case, the gaps include a first gap that is equal to or greater than the first predetermined value G1, a second gap that is less than the first predetermined value G1 and is equal to or greater than the second predetermined value G2, and a third gap that is less than the second predetermined value G2. have. Therefore, the print medium A has a first gap area A1, a second gap area A2, and a third gap area A3. is doing.

For example, the control device 60 acquires the gap change rate H/L, which is the length H of the gap in the vertical direction that changes per unit length L in the horizontal direction, based on the gap information. If print medium A is provided with a large slope, the rate of change of the gap is greater than or equal to the predetermined rate. In this case, the distance of each gap area on the print medium A in the horizontal direction is short, and the speed of the light irradiation unit 30 moving on the print medium A must be switched in a short time. Therefore, the control device 60 separately performs the first, second, and third scans on the assumption that the predetermined condition is not satisfied.

Therefore, the control device 60 divides the print data into scan print data for each scan, and divides the scan print data into the first gap print data, the second gap print data, and the third gap print data based on the gap information. Divide into print data for gaps. Then, the control device 60 executes the first scan, and while moving the head unit 11 at the first speed, ejects the liquid J from the head 20 onto the first gap area A1 based on the first gap print data. At the same time, light is irradiated from the light irradiation section 30 to the first gap region A1. As a result, the liquid J in the first gap area A1 is cured in the first curing time and printed on the print medium A. FIG.

Then, the control device 60 executes the second scanning without executing the conveying operation. In this second scan, the control device 60 moves the head unit 11 at a second speed faster than the first speed over the printing range of the first scan, while the liquid J is transferred from the head 20 to the second gap area A2. The ink is ejected based on the 2-gap print data, and the light irradiation unit 30 irradiates the second gap region A2 with light. As a result, the liquid J in the second gap area A2 is cured in the second curing time and printed on the print medium A.

Furthermore, the control device 60 executes the third scan without executing the transport operation. In this third scan, the control device 60 moves the head unit 11 at a third speed, which is faster than the second speed, over the printing range of the third scan, and dispenses the liquid J from the head 20 to the third gap area A3. The ink is ejected based on the 3-gap print data, and the light irradiation unit 30 irradiates the third gap region A3 with light. As a result, the liquid J in the third gap region A3 is cured in the third curing time and printed on the print medium A. In this way, by printing on the print medium A by a method according to the shape of the print medium A without changing the moving speed of the light irradiation unit 30 in one scan, the print image quality caused by the shape of the print medium A can be improved. can be suppressed.

On the other hand, if print media A has a small or no slope, the rate of change of the gap is less than the predetermined rate. In this case, the distance of each gap area on the print medium A in the horizontal direction is long, and the number of times the light irradiation unit 30 moving on the print medium A switches the speed in one scan is small or not present. Therefore, the control device 60 performs the first light irradiation operation, the second light irradiation operation, and the third light irradiation operation in one scan, assuming that the predetermined condition is satisfied. Thereby, the control device 60 moves the head unit 11 at the first speed in the first light irradiation operation, moves the head unit 11 at the second speed in the second light irradiation operation, and moves the head unit 11 in the third light irradiation operation. 11 is moved at a third speed. In this manner, the moving speed of the light irradiation section 30 is changed in one scan. In this way, by printing the print medium A by a method according to the shape of the print medium A, it is possible to suppress deterioration in print quality due to the shape of the print medium A. FIG.

<Modification 4>
In the printing apparatus 10 according to Modification 4, in Modifications 1 to 3, when the first scan and the second scan are performed separately, the control device 60 performs the second scan and then the first scan. When performed, the first scan illuminates the first gap region in addition to the second gap region.

Specifically, in the second scan, the control device 60 ejects the liquid J from the head 20 to the second gap region A2 in the head unit 11 moving at the second speed, and then ejects the liquid J from the light irradiation section 30 to the second gap region A2. Light is applied to the gap region A2. Then, the control device 60 moves the head unit 11 to the right without conveying the print medium A, and then executes the first scan.

Here, in the head unit 11 that moves at the first speed, the control device 60 ejects the liquid J from the head 20 to the first gap region A1, and then discharges the liquid J from the light irradiation unit 30 to the first gap region A1 and the second gap. Light is applied to the area A2. As a result, the liquid J in the first gap region A1 and the liquid J in the second gap region A2 are irradiated with the light, and the liquid J is cured. At this time, although the illuminance of light in the first gap region A1 is lower than that in the second gap region A2, the liquid J in the first gap region A1 is irradiated with light in both the first scan and the second scan. , the liquid J in the first gap region A1 can be sufficiently cured.

<Other Modifications>
In all the embodiments and modifications described above, the relative movement device 40 moves the head 20 with respect to the print medium A without moving the print medium A in the horizontal direction. On the other hand, the relative movement device 40 may move the stage 51 so as to move the print medium A relative to the head 20 without moving the head 20 in the horizontal direction.

For example, when the relative movement device 40 moves the stage 51 , the relative movement device 40 may include the carrier device 50 . In this case, the carriage 42 carries the stage 51 and the stage support table 53 supports the moving rails 41 . Thereby, the stage 51 can move in the left-right direction along the moving rail 41, and the moving rail 41 can move in the front-rear direction. Therefore, the stage 51 moves laterally and longitudinally with respect to the head unit 12 .

In all of the above-described embodiments and modifications, for example, when the print medium A is tilted in the left-right direction, the control device 60 controls the print medium A and light irradiation as the gap between the light irradiation unit 30 and the print medium A increases. The relative movement device 40 may be controlled such that the relative movement speed of the section 30 is continuously slowed down.

All the embodiments described above may be combined with each other unless they exclude each other. Also, many modifications and other embodiments of the invention will be apparent to those skilled in the art from the above description. Accordingly, the above description is to be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Substantial details of construction and/or function may be changed without departing from the spirit of the invention.

INDUSTRIAL APPLICABILITY The printing apparatus according to the present invention is useful as a printing apparatus or the like capable of suppressing deterioration in print image quality caused by the shape of a printing medium.

10: Printing device 20: Head 30: Light irradiation unit 40: Relative moving device 50: Conveying device 60: Control device

Claims (6)

a head for ejecting liquid onto a print medium;
a light irradiation unit that irradiates the liquid on the print medium with light;
a relative movement device that relatively moves the print medium and the head and the light irradiation unit in a moving direction in which the head and the light irradiation unit are aligned;
a controller;
When the gap of the light irradiator with respect to the print medium is a first gap, the print medium and the light irradiator are more sensitive to each other than when the gap is a second gap smaller than the first gap. and controlling the relative movement device so that the relative movement speed of the printing device is slowed down. a conveying device that conveys the print medium in a conveying direction that intersects the moving direction;
The control device is
scanning including a movement operation for moving the head and the light irradiation unit by the relative movement device, an ejection operation for ejecting the liquid from the head, and a light irradiation operation for irradiating the light from the light irradiation unit; When printing is performed while alternately repeating a transport operation for transporting the print medium by a transport device,
a first light irradiation operation of irradiating a first gap region of the print medium, where the gap is the first gap, with the light while moving the head and the light irradiation unit at a first speed; and the head. and a second light irradiation operation of irradiating a second gap region of the print medium where the gap is the second gap while moving the light irradiation unit at a second speed higher than the first speed. in one said scan, or
The scanning includes a first scanning including the first light irradiation operation without including the second light irradiation operation and a second scanning including the second light irradiation operation without including the first light irradiation operation. 2. The printing apparatus according to claim 1, wherein said first scan and said second scan are performed separately between said transport operation and said transport operation subsequent to said transport operation. The control device is
when the gap satisfies a predetermined condition, performing the first light irradiation operation and the second light irradiation operation in one scan;
3. The printing apparatus according to claim 2, wherein said first scan and said second scan are separately performed when said gap does not satisfy said predetermined condition. if the rate of change of the gap in the movement direction is less than a predetermined rate, the gap satisfies the predetermined condition;
4. The printing apparatus according to claim 3, wherein the gap does not satisfy the predetermined condition when the rate of change of the gap is equal to or greater than the predetermined rate. When the first scan and the second scan are performed separately and the first scan is performed after the second scan is performed, the controller controls the second gap in the first scan. The printing apparatus according to any one of claims 2 to 4, wherein the light is applied to the first gap region in addition to the region. further comprising a stage supporting the print medium;
The printing apparatus according to any one of claims 1 to 5, wherein the relative movement device moves the stage.

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