Liquid discharge apparatus

Abstract

To suppress vibration of a carriage.SOLUTION: A liquid discharge apparatus 100 comprises: a carriage 1 that includes liquid discharge heads 6 and that is reciprocally movable in a main scanning direction; and a stage 7 that reciprocally moves a fabric in a sub scanning direction. The liquid discharge apparatus can perform at least a first liquid discharge operation and a second liquid discharge operation that discharge respectively different liquids. The liquid discharge apparatus is characterized in that at least either of acceleration and velocity of the stage 7 is varied between the first liquid discharge operation and the liquid second discharge operation.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection device. [Background technology]

[0002] There is a liquid ejection device in which a transport member transports the object to be treated with liquid in the sub-scanning direction to a position opposite the carriage, and then a carriage having a liquid ejection head moves back and forth in the main scanning direction, causing the liquid ejection head to eject liquid at each position on the object to be treated with liquid, thereby forming an image.

[0003] For example, the liquid ejection device disclosed in Patent Document 1 (JP 2022-103489 A) selectively uses multiple platens of different sizes, and the platen conveyance speed is changed depending on the platen size.

[0004] In the liquid ejection apparatus described above, in order to improve the productivity of the apparatus, it is required to move the transport member at a higher speed to form an image on the target to which the liquid is to be applied. Summary of the Invention [Problem to be solved by the invention]

[0005] Increasing the movement speed of the transport member can improve the productivity of the device. However, sudden acceleration and deceleration of the transport member can cause vibrations. These vibrations can cause the carriage carrying the liquid ejection head to vibrate, which can lead to the formation of abnormal images, such as images with vertical unevenness, on the target onto which the liquid is applied.

[0006] An object of the present invention is to suppress vibration of the carriage. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a liquid ejection device that has a liquid ejection head, a carriage that can move back and forth in a main scanning direction, and a transport member that moves a target to which liquid is to be applied back and forth in a sub-scanning direction, and that can perform at least a first liquid ejection operation and a second liquid ejection operation that eject different liquids, and is characterized in that at least one of the acceleration or speed of the transport member is changed between the first liquid ejection operation and the second liquid ejection operation. [Effects of the Invention]

[0008] According to the present invention, it is possible to suppress the vibration of the carriage. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing a schematic configuration of a liquid ejection device according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram illustrating an example of an abnormal image. [Figure 3] 10 is a flowchart illustrating an example of a printing process. [Figure 4] 1A and 1B are diagrams showing the transition of the stage speed during printing operations, in which (a) shows the pre-processing and white printing operations, and (b) shows the color printing operation. [Figure 5] 10(a) and 10(b) are diagrams showing the maximum speed and acceleration settings for pre-processing printing, white printing, and color printing, respectively. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations will be appropriately simplified or omitted. In the following description, a liquid ejection device that ejects liquid onto fabric as a liquid application target will be described as an example of the liquid ejection device of the present invention.

[0011] FIG. 1 shows a perspective view of a liquid ejection device according to one embodiment of the present invention. The X direction shown in FIG. 1 is the main scanning direction or the left-right direction of the liquid ejection device. The Y direction is the transport direction of the fabric (the object to be printed or the object to which liquid is applied), or the movement direction of the stage (and platen), or the sub-scanning direction, or the front-to-back direction of the liquid ejection device. Note that the stage moves back and forth, and the fabric is transported back and forth. The Z direction is the up-down direction of the liquid ejection device, and is the direction perpendicular to the mounting surface of the platen. The X, Y, and Z directions are perpendicular to one another. However, these directions do not necessarily have to be perpendicular to one another.

[0012] 1, the liquid ejection device 100 includes a first carriage 1A and a second carriage 1B, a pair of first side plates 2A and a pair of second side plates 2B, a first adjustment plate 3A as a pair of holding members, a second adjustment plate 3B as a pair of holding members, a first guide rod 4A as a pair of guide members, and a second guide rod 4B as a pair of guide members. Hereinafter, the first carriage 1A and the second carriage 1B will also be referred to as carriage 1, the first side plate 2A and the second side plate 2B as side plate 2, the first adjustment plate 3A and the second adjustment plate 3B as adjustment plate 3, and the first guide rod 4A and the second guide rod 4B as guide rod 4.

[0013] Each side plate 2 is provided on both the left and right sides of the liquid ejection device 100, and is fixed to a main body 101 of the liquid ejection device 100. The side plates 2 hold an adjustment plate 3 so that it can move in the Y and Z directions.

[0014] Both ends of the guide rod 4 are held by the adjustment plates 3. Each adjustment plate 3 holds two guide rods 4 in the Y direction.

[0015] The carriage 1 is supported by a pair of guide rods 4 so as to be movable on the guide rods 4. The carriage 1 has a plurality of liquid ejection heads 6. The nozzle surfaces of the liquid ejection heads 6 are provided on the underside thereof.

[0016] A rail 5 is provided on the main body 101 of the liquid ejection device 100 along the Y direction. A stage 7 serving as a transport member is provided on the rail 5. A platen 8 is held on the stage 7. The platen 8 holds fabric as a printing target or a target for liquid application. Specifically, the fabric is placed on a placement surface 8a of the platen 8, which is the surface on which the liquid application target is placed. This placement surface 8a is a surface perpendicular to the Z direction. However, it does not have to be strictly perpendicular.

[0017] The stage 7 is provided so as to be able to move back and forth on rails 5. This back and forth movement of the stage 7 transports the fabric on the platen 8 in the sub-scanning direction, causing liquid to be ejected onto the fabric. In other words, the stage 7 moves the fabric to a position opposite the carriage 1, and the carriage 1 moves back and forth in direction X on the guide rod 4, causing the liquid ejection head 6 of the carriage 1 to eject ink onto the fabric. In this way, an image is formed on the fabric. The platen 8 can also be moved in the Z direction relative to the stage 7, allowing the height of the placement surface 8a to be adjusted.

[0018] By having a plurality of carriages 1, the liquid ejection device 100 can eject inks of different colors onto fabric, and can increase the printing speed onto fabric, thereby improving the productivity of the device.

[0019] During the image formation operation on the fabric by the liquid ejection head 6, once the carriage 1 has finished ejecting liquid onto a predetermined row of the fabric in the sub-scanning direction by reciprocating motion, the stage 7 moves in the sub-scanning direction to position the next row of fabric at the liquid ejection position of the liquid ejection head 6. Then, with the fabric on the stopped stage 7, the carriage 1 moves back and forth in the same way to eject liquid onto the next row of fabric. By repeating this process, it is possible to eject liquid onto the entire image formation portion of the fabric.

[0020] However, this intermittent movement of the stage 7 in the sub-scanning direction causes the stage 7 to accelerate and then decelerate, resulting in vibration of the stage 7. This vibration is transmitted from the main body 101 to the guide rod 4, causing the carriage 1 to vibrate as well. The vibration of the carriage 1 during the liquid ejection operation can result in abnormal images, such as the formation of periodic unevenness in the main scanning direction (vertical stripes extending in the sub-scanning direction) on the fabric, as shown in Figure 2. Note that Figure 2 shows an image with periodic unevenness (vertical stripes) that occurs when a solid image is formed.

[0021] To address this issue, it is possible to reduce the vibration of the carriage 1 and prevent the formation of abnormal images by reducing the acceleration of the stage 7 or by leaving a time gap after the movement of the stage 7. However, this results in another problem: an increase in printing time.

[0022] The printing process in this embodiment will be described below, and the configuration of this embodiment that suppresses the formation of abnormal images due to the vibration of the carriage 1 will be described.

[0023] The liquid ejection device of this embodiment can perform three types of printing: color printing (first liquid ejection operation), white printing (second liquid ejection operation), and pretreatment printing (third liquid ejection operation). As an example, white printing and color printing are performed using a liquid ejection head provided on carriage 1A in FIG. 1. Color printing ejects inks of cyan, magenta, yellow, and black. However, this combination is not necessarily limited, as long as an image of the desired color can be formed. Black-and-white printing, in which only black ink is ejected, may also be performed. In other words, this color printing is a printing operation that forms an image on the fabric to which liquid is applied. White printing is an operation that prints a white background on the surface of the fabric before color printing. Pretreatment printing is performed using a liquid ejection head provided on carriage 1B in FIG. 1, ejecting a pretreatment liquid. Pretreatment printing is a printing operation other than white printing and color printing, which is a printing operation that forms an image, and is performed before the white printing and color printing operations. However, the types of other printing operations are not limited to these.

[0024] FIG. 3 is a flowchart showing an example of a printing process according to this embodiment. 3, when a print job is received, the control unit of the liquid ejection device determines whether pre-processing printing and white printing are performed (S1, S2A, S2B). This results in four types of printing operations. Specifically, there are four types: performing all three types of printing operations (steps S4A1 to S4A4), performing pre-processing printing and color printing (S3B1, S3B2), performing white printing and color printing (S3C1, S3C2), and performing color printing only (S3D1).

[0025] In this embodiment, the stage 7 is moved back and forth once per printing operation. In other words, a liquid ejection operation is performed by either carriage 1A or carriage 1B with one reciprocating movement of the stage 7. However, different printing operations may be performed by ejecting liquid from each carriage with one reciprocating movement. Furthermore, white printing may be performed multiple times (for example, twice) by moving the stage 7 back and forth multiple times.

[0026] In the liquid ejection device of this embodiment, the acceleration and speed of the stage 7 (and platen 8) in the above-mentioned color printing operation (printing operation that forms an image) are set to be smaller than the acceleration and speed of the stage 7 (and platen 8) in the white printing operation and pre-processing printing operation (other printing operations). However, the speed or acceleration of the color printing operation (printing operation that forms an image) may be set to be smaller than the acceleration or speed of either the white printing operation or the pre-processing printing operation (other printing operations).

[0027] In operations other than those for forming an image on fabric, such as the white printing operation and the pre-processing printing operation, even if an abnormal image such as that shown in FIG. 2 is formed, it is unlikely to be visually recognized as a defective image. Conversely, in the color printing operation, which is an operation for forming an image on fabric, the formation of an abnormal image is likely to be visually recognized as a defective image. Therefore, by setting the speed or acceleration of the color printing operation (the printing operation for forming an image) to be smaller than that of other printing operations, as in this embodiment, it is possible to minimize the time required for the entire printing operation while minimizing vibration of the stage 7 during the color printing operation. In other words, it is possible to achieve both productivity of the liquid ejection device and suppression of abnormal images.

[0028] Figure 4 shows the transition of stage speed during printing operations, with the horizontal axis representing time and the vertical axis representing speed. The dotted line in Figure 4(a) represents the white printing operation and pre-processing printing operation, and the solid line in Figure 4(b) represents the color printing operation. Range A represents the time period during which the carriage 1 moves back and forth to perform the liquid ejection operation by the liquid ejection head 6.

[0029] As shown in Figure 4(a), when discharging liquid in range A, the stage 7 is stopped at a predetermined position in the sub-scanning direction, and the carriage 1 is moved in the main scanning direction to discharge liquid onto a predetermined row in the sub-scanning direction of the fabric. Then, when the liquid discharge operation for that row is completed, the stage 7 accelerates again and moves a predetermined distance in the sub-scanning direction. By repeating this operation, each printing operation is completed.

[0030] Comparing Figures 4(a) and 4(b), the speed and acceleration are set lower during color printing than during white printing and pre-processing printing. This increases the operation time for color printing, but as mentioned above, it is possible to suppress vibration of the stage 7. Specifically, during color printing, the time it takes for the stage 7 to start accelerating and finish decelerating is longer than during white printing and pre-processing printing, and the movement distance in the sub-scanning direction is the same for each printing operation.

[0031] As an example, in this embodiment, the acceleration of the stage 7 in the white printing operation and the pre-processing printing operation is set to 490 [mm / sec 2 ] and maximum speed is set to 290 [mm / sec], and the acceleration and maximum speed of the color printing operation are set to half of that. However, the ratio of the acceleration and maximum speed of the color printing operation to the acceleration and maximum speed of the white printing operation and pre-processing printing operation is not limited to this. For example, a certain degree of effect can be achieved in suppressing vibration of the stage 7 by setting the acceleration and maximum speed of the color printing operation to be 20% or more lower than the acceleration and maximum speed of the white printing operation and pre-processing printing operation. The speed and acceleration of the stage 7 can be measured using, for example, a laser length measuring device.

[0032] As shown in FIG. 5(a), in this embodiment, the acceleration and maximum speed are set to be the same for the white printing operation and the pre-processing printing operation. Alternatively, as shown in FIG. 5(b), the speed and acceleration may be set to decrease in the order of pre-processing printing, white printing, and color printing. This suppresses vibration of the stage 7 and the occurrence of abnormal images in white printing, where defects are more easily recognized visually than in pre-processing printing. Alternatively, a configuration in which only one of the speed and acceleration is changed may be used.

[0033] The method of acceleration and deceleration is not limited to that described in the above embodiment. For example, the acceleration and deceleration may be performed in stages, or the acceleration may be changed gradually.

[0034] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0035] In the above description, a liquid ejection device having two carriages has been shown, but the liquid ejection device may have only one carriage, or three or more carriages.

[0036] In the above embodiment, fabric is used as an example of a liquid application target, but the present invention is not limited to this and may be applied to any object to which liquid can be applied.

[0037] "Liquid ejection devices" include devices that have a carriage with a liquid ejection head and drive the liquid ejection head to eject liquid. Liquid ejection devices include not only devices that can eject liquid onto objects to which the liquid can adhere, but also devices that eject liquid into air or liquid.

[0038] This "liquid ejection device" can also include means for feeding, transporting, and discharging items onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0039] For example, examples of "liquid ejection devices" include image forming devices, which are devices that eject ink to form images on paper, and three-dimensional modeling devices (three-dimensional modeling devices), which eject modeling liquid onto a powder layer formed from layers of powder in order to create a three-dimensional object (a three-dimensional model).

[0040] Furthermore, the term "liquid ejection device" is not limited to devices that visualize meaningful images such as letters and figures using ejected liquid. For example, it also includes devices that form patterns that have no meaning in themselves, and devices that create three-dimensional images.

[0041] The above-mentioned "liquid-receiving target" means something to which the liquid can be attached at least temporarily, something to which the liquid can be attached and fixed, something to which the liquid can be attached and penetrated, etc. Specific examples include media such as paper, recording paper, film, and cloth, electronic circuit boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all things to which the liquid can be attached.

[0042] The material of the "substance to which a liquid can adhere" may be any material to which a liquid can adhere, even temporarily, such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, or ceramics.

[0043] The aspects of the present invention are as follows, for example. <1> a carriage having a liquid ejection head and capable of reciprocating in a main scanning direction; a transport member that reciprocates a liquid application target in a sub-scanning direction, and the liquid ejection device is capable of performing at least a first liquid ejection operation and a second liquid ejection operation that eject different liquids, The liquid ejection device is characterized in that at least one of the acceleration and the speed of the transport member is changed between the first liquid ejection operation and the second liquid ejection operation. <2> the first liquid ejection operation is a color printing operation, The acceleration or speed of the transport member in the first liquid ejection operation is set to be smaller than that in the second liquid ejection operation. <1> The liquid ejection device is as described above. <3> The third liquid ejection operation can be performed, the second liquid ejection operation is a white printing operation, and the third liquid ejection operation is a printing operation other than color printing and white printing, The acceleration or speed of the transport member decreases in the order of the third liquid discharge operation, the second liquid discharge operation, and the first liquid discharge operation. <2> The liquid ejection device is as described above. [Explanation of symbols]

[0044] 1 carriage 6 Liquid ejection head 7 Stage (transport member) 8 Platen 100 Liquid dispensing device X main scanning direction Y sub-scanning direction [Prior art documents] [Patent documents]

[0045] [Patent Document 1] JP 2022-103489 A

Claims

1. a carriage having a liquid ejection head and capable of reciprocating in a main scanning direction; a transport member that reciprocates a liquid application target in a sub-scanning direction, and the liquid ejection device is capable of performing at least a first liquid ejection operation and a second liquid ejection operation that eject different liquids, A liquid ejection apparatus, characterized in that at least one of the acceleration and the speed of the transport member is changed between the first liquid ejection operation and the second liquid ejection operation.

2. the first liquid ejection operation is a color printing operation, 2. The liquid ejection apparatus according to claim 1, wherein the acceleration or speed of the transport member in the first liquid ejection operation is set to be smaller than that in the second liquid ejection operation.

3. The third liquid ejection operation is executable, the second liquid ejection operation is a white printing operation, and the third liquid ejection operation is a printing operation other than color printing and white printing, 3. The liquid ejection apparatus according to claim 2, wherein the acceleration or speed of the transport member decreases in the order of the third liquid ejection operation, the second liquid ejection operation, and the first liquid ejection operation.

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