Liquid dispensing device, liquid dispensing method, and program

Abstract

To improve painting accuracy. [Solution] A liquid dispensing device for coating a surface to be painted by dispensing liquid, comprising: a head that individually dispenses liquid from a plurality of nozzles arranged in the main scanning direction formed on a nozzle plate; a variable mechanism that changes the relative position and relative orientation with respect to the surface to be painted; and a control unit that controls the operation of the head and the variable mechanism, respectively. The control unit uses a group of nozzles selected from the plurality of nozzles based on the maximum vibration frequency component included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and a predetermined relative movement speed of the head by the variable mechanism, to form a correction pattern on the surface to be painted. Based on the correction pattern, it acquires information on the rotation of the head with a rotation axis along the normal of the nozzle plate as the center of rotation, and based on the information on the rotation of the head, it corrects the rotation of the head which is moved relative by the variable mechanism, and controls the dispensing of liquid from the head.

Description

Technical Field

[0001] The present disclosure relates to a liquid ejection device, a liquid ejection method, and a program.

Background Art

[0002] Conventionally, a liquid ejection device that ejects liquid from a head to paint a painting target surface is known.

[0003] For example, Patent Document 1 discloses a liquid ejection device including a head, a moving mechanism that changes the relative position between the painting target surface and the head, and a detection unit that detects the relative position between the painting target surface and the head. In this liquid ejection device, while the moving mechanism relatively scans the head along a first scanning path, the detection unit detects the position regarding the first scanning path, and while relatively scanning the head along a second scanning path based on the detection result by the detection unit, the head performs an operation of ejecting liquid onto the painting target surface.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the liquid ejection device of Patent Document 1, coating unevenness may occur due to vibrations or the like generated in at least one of the head and the variable mechanism when the liquid ejection device performs a coating operation, and the coating accuracy may decrease.

[0005] An object of the present disclosure is to improve coating accuracy.

Means for Solving the Problems

[0006] A liquid dispensing device according to one aspect of the present disclosure is a liquid dispensing device for dispensing liquid to paint a surface to be painted, comprising: a head including a nozzle plate, which individually dispenses liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate; a variable mechanism for changing the relative position and relative orientation of the head with respect to the surface to be painted; and a control unit for controlling the operation of the head and the variable mechanism, respectively, wherein the control unit uses a group of nozzles selected from the plurality of nozzles based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and a predetermined relative movement speed of the head by the variable mechanism to form a correction pattern on the surface to be painted, and based on the correction pattern formed on the surface to be painted, it acquires information on the rotation of the head with a rotation axis along the normal of the nozzle plate as the center of rotation, and based on the information on the rotation of the head, it corrects the rotation of the head which is moved relative to the variable mechanism and controls the dispensing of the liquid from the head. [Effects of the Invention]

[0007] According to this disclosure, painting accuracy can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the overall configuration of the liquid dispensing device according to the first embodiment. [Figure 2] This is a block diagram showing an example configuration of a liquid dispensing device according to the first embodiment. [Figure 3] This diagram shows the configuration of the supply mechanism of the liquid dispensing device according to the first embodiment. [Figure 4] This is a schematic perspective view showing the configuration of the head of the liquid dispensing device according to the first embodiment. [Figure 5] Figure 4 is a schematic cross-sectional view of the head in plane V. [Figure 6] This figure shows a plurality of nozzles in the head of a liquid dispensing device according to the first embodiment. [Figure 7] This diagram illustrates the basic operation of the relative movement of the heads of the liquid dispensing device according to the first embodiment. [Figure 8] This is a timing chart illustrating the basic discharge operation of the head of the liquid dispensing device according to the first embodiment. [Figure 9] This is a block diagram showing the functional configuration of the control unit of the liquid dispensing device according to the first embodiment. [Figure 10] This diagram shows uneven paint application caused by head rotation during the painting process. [Figure 11] This diagram illustrates a method for correcting head rotation during painting operations using a correction pattern. [Figure 12] This diagram illustrates the correction error caused by head vibration during painting operations in a correction method using a correction pattern. [Figure 13] This diagram illustrates the nozzle group selected in the liquid dispensing device according to the first embodiment. [Figure 14] This figure shows a correction pattern formed by the selected nozzle group in the liquid dispensing device according to the first embodiment. [Figure 15] This is a flowchart showing the operation of the liquid dispensing device according to the first embodiment. [Figure 16A] This figure shows the rotation of the head in response to relative movement in the main scanning direction in the liquid dispensing device according to the first embodiment. [Figure 16B] This figure shows how the head's posture changes to compensate for the rotation of the head in response to relative movement in the main scanning direction in the liquid dispensing device according to the first embodiment. [Figure 16C] This figure shows how the rotation of the head in response to relative movement in the main scanning direction is corrected in the liquid dispensing device according to the first embodiment. [Figure 17A] This is a block diagram showing the configuration of a liquid dispensing device according to the second embodiment. [Figure 17B] This is a schematic diagram showing the configuration of a liquid dispensing device according to the second embodiment. [Figure 17C] This diagram shows the configuration of the media board. [Figure 17D] It is a plan view showing a media plate on which a test pattern is formed. [Figure 17E] It is an enlarged view of the P part in FIG. 17D. [Figure 18] It is a flowchart showing the operation of the liquid ejection device according to the second embodiment. [Figure 19] It is a block diagram showing the functional configuration of the control unit of the liquid ejection device according to the third embodiment. [Figure 20] It is a diagram for explaining the state of detecting the vibration amplitude by the liquid ejection device according to the third embodiment. [Figure 21] It is a diagram for explaining the shift of the head in the sub-scanning direction. [Figure 22] It is a block diagram showing the functional configuration of the control unit of the liquid ejection device according to the fourth embodiment. [Figure 23] It is a diagram showing an imaging image of a correction pattern in the liquid ejection device according to the fourth embodiment. [Figure 24] It is a schematic diagram exemplifying the configuration and arrangement of the imaging unit in the liquid ejection device according to the fourth embodiment.

Embodiments for Carrying Out the Invention

[0009] The liquid ejection device, liquid ejection method, and program according to the embodiments of the present invention will be described in detail with reference to the drawings. However, the following embodiments exemplify the liquid ejection device, liquid ejection method, and program for embodying the technical idea of the present embodiment, and are not limited thereto. Note that the sizes, positional relationships, etc. of the members shown in each drawing may be exaggerated for clarity of explanation. Further, in the following description, the same names and reference numerals denote the same or equivalent members, and detailed descriptions thereof will be omitted as appropriate.

[0010] In the embodiment, "along" includes that the object has an inclination of ±20° or less with respect to these axes. Further, in the embodiment, "orthogonal" may include an error of ±10° or less with respect to 90°.

[0011] [First Embodiment] <Example configuration of liquid dispensing device 100> (Overall structure) The configuration of the liquid dispensing device according to the first embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram showing an example of the overall configuration of the liquid dispensing device 100 according to the first embodiment. Figure 2 is a block diagram showing an example of the configuration of the liquid dispensing device 100.

[0012] The liquid dispensing device 100 is a device that dispenses liquid to paint a surface to be painted. The liquid dispensed by the liquid dispensing device 100 adheres to the surface to be painted, dries and hardens, and thus the surface is painted. The liquid dispensing method of the liquid dispensing device 100 is, for example, a continuous dispensing method. Continuous dispensing methods include a valve method that controls dispensing by opening and closing the nozzle by controlling the operation of a valve body, or a continuous method that charges ink droplets continuously dispensed from the nozzle, bends them with a deflection electrode and sprays them onto the printing surface.

[0013] The surface to be painted is, for example, a surface included in the body of an automobile. However, the surface to be painted is not limited to the body of an automobile, but may also be a surface included in vehicles, aircraft, ships, etc. Vehicles include automobiles, trucks, trains, etc. The surface to be painted may include curved shapes. The curved shape of the surface to be painted is determined according to the design of the object to be painted. However, the surface to be painted may include flat shapes, or it may include both curved and flat shapes. Furthermore, the surface to be painted may be an impermeable surface. Impermeability refers to the property that the applied liquid does not penetrate into the interior. However, the surface to be painted is not limited to an impermeable surface, but may also be a permeable surface.

[0014] As shown in Figures 1 and 2, the liquid dispensing device 100 according to this embodiment includes a head 1 for dispensing liquid, a variable mechanism 2 for changing the relative position and orientation of the head 1 with respect to the surface to be painted, and a control unit 3 for controlling the operation of the head 1 and the variable mechanism 2, respectively. In the example shown in Figures 1 and 2, the liquid dispensing device 100 also includes a supply mechanism 4 for supplying the liquid dispensed by the head 1 to the head 1. Furthermore, the liquid dispensing device 100 includes a vibration detection unit 5 for detecting vibrations generated in at least one of the head 1 and the variable mechanism 2 when the liquid dispensing device 100 performs a painting operation, and an imaging unit 6 for capturing a correction pattern formed on the surface to be painted.

[0015] The liquid dispensing device 100, under the control of the control unit 3, drives the variable mechanism 2 that supports the head 1 based on predetermined shape data SD of the surface to be painted. The liquid dispensing device 100 paints the surface to be painted by dispensing liquid from the head 1 while changing the relative position and relative orientation between the head 1 and the surface to be painted by driving the variable mechanism 2.

[0016] The number of heads 1 in the liquid dispensing device 100 is not limited to one, and can be changed as appropriate depending on the size and shape of the surface to be painted, or the time required for painting. The configuration of head 1 will be described separately with reference to Figures 4 and 5.

[0017] In the examples shown in Figures 1 and 2, the variable mechanism 2 changes the relative position of the head 1 with respect to the surface to be painted by moving the head 1. The variable mechanism 2 also changes the relative posture of the head 1 with respect to the surface to be painted by changing the posture of the head 1. However, the variable mechanism 2 may change the relative position by moving the surface to be painted, or by changing the posture of the surface to be painted.

[0018] In the examples shown in Figures 1 and 2, the variable mechanism 2 includes a robot arm. The variable mechanism 2 changes the relative position and orientation of the head 1 by driving the robot arm that supports the head 1. From the viewpoint of flexibly and accurately changing the relative position and orientation, it is preferable that the robot arm of the variable mechanism 2 has multiple drive axes. However, the variable mechanism 2 is not limited to a robot arm and may include a gantry mechanism, a linear stage, or a rotary stage, etc. Also, the variable mechanism 2 may include two or more combinations of the robot arm, gantry mechanism, linear stage, or rotary stage, etc. The number of variable mechanisms 2 is not limited to one and can be changed as appropriate to match the number of heads 1. One variable mechanism 2 may support two or more heads 1.

[0019] The variable mechanism 2 may have position sensors such as rotary encoders that output information regarding the relative position and relative orientation of the head 1 supported by the robot arm. The variable mechanism 2 transmits the output of the position sensors to the control unit 3 as position signals relating to the relative position and relative orientation of the head 1. The variable mechanism 2 has the same number of position sensors as the number of axes that change the relative position and relative orientation, and can transmit the output of the position sensors to the control unit 3 for each of the multiple axes. The number of axes for relative position in the variable mechanism 2 is, for example, three axes: the X axis, Y axis, and Z axis, which are orthogonal to each other. The number of axes for relative orientation in the variable mechanism 2 is, for example, three axes: the α axis with the X axis as the center of rotation, the β axis with the Y axis as the center of rotation, and the γ axis with the Z axis as the center of rotation.

[0020] The control unit 3 controls the operation of the head 1 and the variable mechanism 2, respectively. For example, based on predetermined shape data SD of the surface to be painted, the control unit 3 changes the relative position and relative orientation between the head 1 and the surface to be painted, while discharging liquid from the head 1.

[0021] As shown in Figure 2, the control unit 3 includes a CPU (Central Processing Unit) 31, a ROM (Read Only Memory) 32, and a RAM (Random Access Memory) 33. The control unit 3 also includes an HDD (Hard Disk Drive) / SSD (Solid State Drive) 34, a device connection I / F (Interface) 35, and a communication I / F 36. These are electrically connected to each other via a system bus SB, enabling communication between them.

[0022] The CPU 31 uses the RAM 33 as a workspace and controls the operation of the entire control unit 3 by executing processes specified in the program stored in the ROM 32. The ROM 32 is a non-volatile memory that stores programs for controlling operations such as recording to the CPU 31 and other fixed data. The RAM 33 is a volatile memory that temporarily stores various data used in operations such as liquid ejection by the head 1 and driving the variable mechanism 2. The HDD / SSD 34 is a non-volatile memory that stores shape data SD of the surface to be painted, and image data of patterns and characters when patterns and characters are drawn on the surface to be painted.

[0023] The device connection interface 35 is an interface for enabling communication between the head 1, the variable mechanism 2, and the supply mechanism 4. The communication interface 36 is an interface for enabling communication between the control unit 3 and an external device such as a host PC (Personal Computer).

[0024] The supply mechanism 4 operates under the control of the control unit 3. Details of the configuration of the supply mechanism 4 are described below with reference to Figure 3.

[0025] For example, an acceleration sensor can be used in the vibration detection unit 5. The vibration detection unit 5 is located in at least one of the head 1 and the variable mechanism 2. The vibration detection unit 5 transmits the vibration detection result to the control unit 3.

[0026] The imaging unit 6 is attached to the head 1 and moves relative to the head 1 along with the relative movement of the head 1 by the variable mechanism 2, while imaging the correction pattern formed on the surface to be painted S. The imaging unit 6 may image multiple parts of the correction pattern to acquire multiple images. However, the imaging unit 6 may be positioned separately from the head 1, and the correction pattern formed on the surface to be painted S may be included in a single image.

[0027] The imaging unit 6 can be, for example, a camera having a lens and an image sensor that captures an image from the lens. The image sensor can be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), etc. The imaging unit 6 outputs the captured image to the control unit 3.

[0028] In addition to the components shown in Figures 1 and 2, the liquid dispensing device 100 may also have, for example, a maintenance mechanism. The maintenance mechanism maintains the liquid dispensing state of the head 1. The maintenance mechanism removes viscous liquid or foreign matter adhering to the nozzle surface or present inside the head 1 by using a wiper that wipes the nozzle surface of the head 1, or a suction pump that sucks liquid from inside the head 1. By removing viscous liquid or foreign matter, the maintenance mechanism can reduce dispensing abnormalities such as non-dispensing, misaligned discharge, or fluctuations in discharge speed from the head 1, and maintain the dispensing state of the head 1 in a normal state.

[0029] The liquid dispensing device 100 may further include a display unit that displays a setting screen for liquid application conditions etc. by the liquid dispensing device 100, and an operation unit which is an operation input device such as a touch panel, keyboard, or mouse that accepts operation of the liquid dispensing device 100.

[0030] (Configuration of supply mechanism 4) Figure 3 shows an example of the configuration of the supply mechanism 4.

[0031] The print head 1 includes a print head 1Y for dispensing yellow (Y) liquid, a print head 1M for dispensing magenta (M) liquid, a print head 1C for dispensing cyan (C) liquid, and a print head 1K for dispensing black (K) liquid. In addition to the print heads for each of these colors, the print head 1 may further include a print head for dispensing an overcoat liquid, or a print head for dispensing a primer liquid or a white liquid, or other liquids. The supply mechanism 4 is capable of supplying each color of liquid to the print head 1.

[0032] The supply mechanism 4 includes a liquid tank 330, which serves as a sealed container for holding the liquids 325 of each color discharged from the head 1. The liquid tank 330 and the inlet (supply port) of the head 1 are connected via tubes 333 to allow liquid to flow through them.

[0033] Meanwhile, the liquid tank 330 is connected to the compressor 230 via a pipe 331 containing an air regulator 332, and the compressor 230 supplies pressurized air. As a result, the pressurized liquids 325 of each color are supplied to the inlet of the head 1, and the liquid discharge device 100 discharges the liquids 325 from the nozzle of the head 1.

[0034] (Configuration of Head 1) The configuration of head 1 will be described with reference to Figures 4 to 6. Figure 4 is a schematic perspective view showing an example of the configuration of head 1. Figure 5 is a schematic cross-sectional view of head 1 in plan V of Figure 4. Figure 6 is a schematic bottom view of head 1 showing the multiple nozzles 311 in head 1.

[0035] As shown in Figures 4 and 5, in this embodiment, the head 1 includes a nozzle plate 321 and discharges liquid individually from a plurality of nozzles 311 formed on the nozzle plate 321 and arranged in the main scanning direction A. The head 1 has a plurality of discharge modules 340 arranged in one or more rows within the housing 110.

[0036] Head 1 has a supply port 111 and a recovery port 112. The supply port 111 supplies pressurized liquid from the outside to the discharge module 340. The recovery port 112 discharges any liquid that was not discharged to the outside. A connector 113 is located in the housing 110.

[0037] As shown in Figure 5, the discharge module 340 includes a nozzle plate 321 equipped with a nozzle 311 for discharging liquid, a flow path 322 through which the nozzle 311 communicates and which supplies pressurized liquid, and a piezoelectric element 324 that drives a needle-shaped valve body for opening and closing the nozzle 311. The nozzle surface 350 corresponds to the surface of the nozzle plate 321 in the direction from which the liquid is discharged. The normal N of the nozzle plate 321 is also the normal N of the nozzle surface 350.

[0038] The nozzle plate 321 is joined to the housing 110. The flow path 322 is a common flow path for multiple discharge modules 340 provided in the housing 110. The liquid discharge device 100 supplies pressurized liquid from the supply port 111 through the flow path 322 and discharges the liquid from the recovery port 112. During the period when liquid is being discharged onto the surface to be painted, the discharge of liquid from the recovery port 112 may be temporarily suspended in order to avoid reducing the discharge efficiency of the liquid from the nozzle 311.

[0039] As shown in Figure 6, the head 1 has a plurality of nozzles 311 on a nozzle surface 350 that faces the surface to be painted when performing a painting operation. The head 1 can individually discharge liquid from the plurality of nozzles 311 arranged in the main scanning direction A. In the example shown in Figure 6, the head 1 includes a nozzle row 351 consisting of three nozzles 311 arranged in a sub-scanning direction B perpendicular to the main scanning direction A. Nine nozzle rows 351 are arranged in the main scanning direction A. In other words, in the example shown in Figure 6, there are 27 nozzles 311 in total.

[0040] The nine nozzles aligned in the main scanning direction A are positioned at a slightly inclined angle relative to the main scanning direction A. This reduces the spacing between liquid droplets that land on the surface to be painted in the sub-scanning direction B. Because the spacing between liquid droplets that land on the surface to be painted in the sub-scanning direction B is reduced, when the head 1 is moved relative to the main scanning direction A, the spacing between the linear patterns formed on the surface to be painted corresponding to the multiple nozzles 311, each extending in the main scanning direction A, is reduced in the sub-scanning direction B. This reduced spacing between the multiple linear patterns in the sub-scanning direction B reduces unevenness in the thickness of the liquid layer on the surface to be painted, while enabling efficient application of the liquid to the surface to be painted.

[0041] (Basic movements of head 1, relative movement, and discharge) Before explaining the functional configuration of the control unit 3, we will now describe the basic operations of the relative movement and discharge of the head 1.

[0042] Figure 7 illustrates the basic operation of the relative movement of the head 1 with respect to the surface S to be painted. As shown in Figure 7, the head 1 moves relative to the main scanning direction A and the sub-scanning direction B by the variable mechanism 2, performing so-called raster scanning while dispensing liquid onto the surface S to be painted.

[0043] Specifically, first, head 1 moves relative to the positive main scanning direction A, indicated by the arrow showing the main scanning direction A. Head 1 begins discharging liquid when it enters the area to be coated on the surface S. Head 1 continuously discharges liquid while moving relative to the positive main scanning direction A, forming a linear pattern L1 extending in the main scanning direction A on the area to be coated. Head 1 stops discharging liquid when it exits the area to be coated.

[0044] Next, head 1 moves a predetermined line break distance relative to the positive sub-scanning direction B, indicated by the arrow indicating sub-scanning direction B. After moving the line break distance in sub-scanning direction B, head 1 moves in the negative main scanning direction A, which is the opposite direction to the positive main scanning direction A. Head 1 starts discharging the liquid at the moment it enters the area to be painted on the surface S. Head 1 continuously discharges the liquid while moving relative to the negative main scanning direction A, forming a linear pattern L2 extending in the main scanning direction A in the area to be painted. Head 1 stops discharging the liquid at the moment it exits the area to be painted.

[0045] Next, head 1 forms a linear pattern L3 while moving in the positive main scanning direction A, similar to when forming linear pattern L1. Subsequently, head 1 forms a linear pattern L4 while moving in the negative main scanning direction A, similar to when forming linear pattern L2.

[0046] The liquid dispensing device 100 can paint the surface to be painted S by repeatedly performing the operation of forming multiple linear patterns L, including the linear patterns L1, L2, L3, and L4 described above. When the surface to be painted S is flat, the main scanning direction A and the sub-scanning direction B are approximately orthogonal. On the other hand, when the surface to be painted S is curved, the main scanning direction A and the sub-scanning direction B intersect at an angle that deviates from orthogonal depending on the curvature of the curved surface.

[0047] Next, Figure 8 is a timing chart illustrating the basic discharge operation of head 1.

[0048] In Figure 8, the variable mechanism 2 periodically transmits a position signal P to the control unit 3 regarding the current position of the head 1, which is supported by the robot arm. The position signal regarding the current position includes position information (in mm) in the X, Y, and Z axes, and attitude information (in degrees) in the α, β, and γ axes.

[0049] The variable mechanism 2 outputs a synchronization signal T1 to the control unit 3 at the timing of entering the area to be painted on the surface S, in order to synchronize the movement of the robot arm with the liquid discharge operation of the head 1. The control unit 3 generates interval signals T2 at intervals in which liquid should be discharged, according to the position signal P received from the variable mechanism 2. In the example shown in Figure 8, the control unit 3 generates interval signals T2 every time the relative movement is 100 dpi, or 0.254 mm, in a three-dimensional space including the X, Y, and Z axes. The control unit 3 also generates a discharge signal T3 with a discharge time Tout after a delay time Td triggered by the interval signal T2, and outputs it to the head 1. The head 1 continuously discharges liquid for a duration of discharge time Tout, which coincides with the time when the discharge signal T3 is Low. The delay time Td and discharge time Tout are variable according to the shape data SD of the surface S, etc.

[0050] (Functional configuration of the control unit 3) The functional configuration of the control unit 3 will be explained with reference to Figures 9 to 14. Figure 9 is a block diagram showing an example of the functional configuration of the control unit 3. Figure 10 is a diagram showing uneven painting due to one rotation of the head during painting. Figure 11 is a diagram illustrating a method for correcting one rotation of the head during painting using a correction pattern. Figure 12 is a diagram illustrating the correction error due to head vibration during painting in the correction method using a correction pattern. Figure 13 is a diagram illustrating the nozzle group 360 selected in the liquid discharge device 100. Figure 14 is a diagram showing the correction pattern E formed by the nozzle group 360 selected in the liquid discharge device 100. Note that the head 1 shown in Figures 10 to 14 is the head 1 as seen from the nozzle surface 350 side.

[0051] As shown in Figure 9, the control unit 3 includes an input unit 301, a nozzle group selection unit 302, a rotation information acquisition unit 303, a correction data creation unit 304, a head control unit 305, a variable mechanism control unit 306, a supply control unit 307, and an output unit 308.

[0052] The functions of the input unit 301 and the output unit 308 are realized by the device connection I / F 35 and communication I / F 36, etc., shown in Figure 2. However, the functions of the input unit 301 and the output unit 308 may also be realized by the CPU 31 loading the program stored in the ROM 32 into the RAM 33 and executing the processing defined in the program. The functions of the nozzle group selection unit 302, rotation information acquisition unit 303, correction data creation unit 304, head control unit 305, variable mechanism control unit 306, and supply control unit 307 are realized by the CPU 31 loading the program stored in the ROM 32 into the RAM 33 and executing the processing defined in the program.

[0053] Some of the functional configurations of the control unit 3 may be implemented by equipment or devices other than the control unit 3. Examples of equipment other than the control unit 3 include the head 1 or the variable mechanism 2. Other devices include a PC (Personal Computer) that is connected to the control unit 3 in a communicative manner. Furthermore, some of the functional configurations of the control unit 3 may be implemented through distributed processing between the control unit 3 and equipment or devices other than the control unit 3.

[0054] Here, as shown in Figure 10, during the painting operation of the liquid discharge device 100, the head 1, which is moved relative to the nozzle by the variable mechanism 2, may rotate around a rotation axis RC that is aligned with the normal N of the nozzle plate 321. When the head 1 rotates around the rotation axis RC, the position of the nozzle 311 shifts from the desired position. The further the nozzle 311 is from the rotation axis RC in the main scanning direction A, the greater the positional displacement due to rotation. Due to the positional displacement of the nozzle 311, the spacing between the multiple linear patterns L formed on the surface to be painted by discharging liquid from each of the multiple nozzles 311 while the head 1 moves relative to the main scanning direction A becomes uneven in the sub-scanning direction B. The uneven spacing between the multiple linear patterns L in the sub-scanning direction B results in an uneven thickness of the liquid layer formed on the surface to be painted, causing uneven painting.

[0055] The liquid dispensing device 100 can, for example, form a correction pattern on the surface to be painted before painting, in order to reduce unevenness in the paint, and correct the rotation of the head 1 based on the correction pattern. The correction pattern is a plurality of linear patterns extending in the main scanning direction A, which are formed by dispensing liquid from a group of nozzles including a predetermined plurality of nozzles 311 on the head 1 while moving the head 1 relative to the main scanning direction A. Based on the correction pattern formed on the surface to be painted, the liquid dispensing device 100 can acquire information on the rotation of the head 1 during the painting operation and correct the rotation of the head 1 by changing the posture of the head 1 so that the rotation of the head 1 is reduced.

[0056] Figure 11 shows a nozzle group 360 and an example of a correction pattern E formed using the nozzle group 360. In the example shown in Figure 11, the nozzle group 360 includes nozzle 311-1 and nozzle 311-2. The correction pattern E includes a correction pattern E1 formed by the liquid discharged from nozzle 311-1 and a correction pattern E2 formed by the liquid discharged from nozzle 311-2.

[0057] As the rotation of the head 1 around the rotation axis RC changes the positions of nozzles 311-1 and 311-2, the interval d between correction patterns E1 and E2 in the sub-scanning direction B changes. The liquid discharge device 100 can acquire information about the rotation of the head 1 based on this interval d. Based on the information about the rotation of the head 1 acquired in advance using the correction pattern E, the liquid discharge device 100 corrects the rotation of the head 1 by changing the posture of the head 1 so that the rotation of the head 1 is reduced during the painting operation.

[0058] From the standpoint of acquiring information regarding the rotation of the head 1 with high accuracy, it is preferable that the multiple nozzles used as a nozzle group 360 be as far away as possible from the rotation axis RC of the head 1 in the main scanning direction A. For example, among the multiple nozzles included in the head 1, it is preferable to use the nozzle located furthest upstream and the nozzle located furthest downstream in the main scanning direction A.

[0059] On the other hand, head 1 may vibrate when it moves relative to the main scanning direction A during painting. Due to this vibration, as shown in Figure 12, the correction pattern E includes a pattern that is displaced in the sub-scanning direction B according to its relative position in the main scanning direction A. In the example shown in Figure 12, the correction pattern E includes a sinusoidal pattern that is displaced in the sub-scanning direction B according to its relative position in the main scanning direction A. The phase of the displacement of the correction pattern E in the sub-scanning direction B may differ for each of the multiple nozzles 311 used as the nozzle group 360. Here, the phase of the displacement of the correction pattern E in the sub-scanning direction B refers to the phase of the pattern that is displaced in the sub-scanning direction B according to its relative position in the main scanning direction A.

[0060] The example shown in Figure 12 illustrates the phase shift of the displacement in the sub-scanning direction B of the correction pattern E for each of the two nozzles 311. The correction pattern E shown in Figure 12 includes correction pattern E1 and correction pattern E2. Correction patterns E1 and E2 are correction patterns formed by liquid discharged from different nozzles 311 in the head 1. The displacement of correction pattern E1 in the sub-scanning direction B is out of phase with the displacement of correction pattern E2 in the sub-scanning direction B. Due to this phase shift, the interval d between correction pattern E1 and correction pattern E2 changes depending on the position in the main scanning direction A. In the example shown in Figure 12, intervals d1, d2, and d3 are different from each other depending on the position in the main scanning direction A. Because the interval d differs depending on the position in the main scanning direction A, it may not be possible to accurately detect the interval d, and therefore, it may not be possible to accurately obtain information about the rotation of the head 1 based on the interval d.

[0061] Furthermore, in the case of a head where multiple nozzle rows are arranged in the sub-scanning direction B and multiple nozzle rows are arranged in the main scanning direction A, the nozzle displacement due to head vibration is often smaller than the nozzle displacement due to head rotation. This is because the longer the length of the multiple nozzle rows arranged in the main scanning direction A, the greater the nozzle displacement due to head rotation, and the relatively larger the nozzle displacement due to head rotation becomes compared to the displacement due to head vibration. Therefore, the direct impact of head vibration on paint unevenness is small. However, due to head vibration, the spacing d changes depending on the position in the main scanning direction A, making it difficult to accurately acquire information about head rotation, resulting in correction errors. Therefore, head vibration indirectly affects paint unevenness as a correction error for head rotation.

[0062] In this embodiment, the control unit 3 acquires information on vibrations generated in at least one of the head 1 and the variable mechanism 2 when the liquid dispensing device 100 performs a painting operation. The control unit 3 selects a group of nozzles 360 from a plurality of nozzles 311 based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibration, and a predetermined relative movement speed of the head 1 by the variable mechanism 2. The control unit 3 dispenses liquid from the selected group of nozzles 360 to form a correction pattern E on the surface to be painted S. Based on the correction pattern E formed on the surface to be painted S, the control unit 3 acquires information on the rotation of the head 1 with the rotation axis RC along the normal N of the nozzle plate 321 as the center of rotation. Based on the information on the rotation of the head 1, the control unit 3 corrects the rotation of the head 1 which is moved relatively by the variable mechanism 2 and controls the dispensing of liquid from the head 1. As a result, in this embodiment, the rotation of the head 1 can be reduced, reducing unevenness in painting and improving painting accuracy.

[0063] For example, the control unit 3 creates correction data that changes the orientation of the head 1 by the variable mechanism 2 at each predetermined teaching position in the main scanning direction A, based on information regarding the rotation of the head 1. The correction data is data that changes the orientation of the head 1 at each of several teaching positions in the main scanning direction A so that the multiple nozzles 311 lined up in the sub-scanning direction B are as parallel as possible to the sub-scanning direction B. Using this correction data, the control unit 3 can correct the rotation of the head 1 which is moved relative to the variable mechanism 2, and control the head 1 to discharge liquid.

[0064] In the example shown in Figure 9, the input unit 301 controls communication with devices other than the control unit 3, thereby inputting shape data SD of the surface to be painted S from devices other than the control unit 3. The devices other than the control unit 3 may be, for example, a connected PC capable of communicating with the control unit 3 via a network such as the Internet, or a portable memory device such as a USB (Universal Serial Bus) memory. The input unit 301 then passes the shape data SD to the head control unit 305 and the variable mechanism control unit 306, respectively.

[0065] Furthermore, the input unit 301 receives the results of vibration detection by the vibration detection unit 5 in Figure 2, which detects vibrations during the painting operation of at least one of the head 1 and the variable mechanism 2. The input unit 301 passes the vibration detection results to the nozzle group selection unit 302. In addition, the input unit 301 receives the captured image of the correction pattern E captured by the imaging unit 6 in Figure 2. The input unit 301 passes the captured image of the correction pattern to the rotation information acquisition unit 303.

[0066] The nozzle group selection unit 302 receives the vibration detection result from the vibration detection unit 5 via the input unit 301. Based on the vibration detection result, the nozzle group selection unit 302 identifies the maximum vibration frequency component with the largest vibration amplitude among the multiple vibration frequency components included in the vibration generated in at least one of the head 1 and the variable mechanism 2 when the liquid discharge device 100 performs a painting operation. Based on the identified maximum vibration frequency component and a predetermined relative movement speed of the head 1 by the variable mechanism 2, the nozzle group selection unit 302 selects a nozzle group 360 from a plurality of nozzles 311.

[0067] For example, the nozzle group selection unit 302 selects a nozzle group 360 in which the phase of the displacement of the correction pattern E in the sub-scanning direction B, corresponding to the relative movement of the head 1 in the main scanning direction A by the variable mechanism 2, is aligned. The nozzle group selection unit 302 then passes information about the selected nozzle group 360 to the head control unit 305.

[0068] Referring to Figure 13, the selection of the nozzle group 360 by the nozzle group selection unit 302 will be explained in more detail. Figure 13 shows a plurality of nozzles 311 formed on the nozzle surface 350. Here, n is an integer. Also, among the plurality of vibration frequency components included in the vibrations generated in at least one of the head 1 and the variable mechanism 2 when the liquid discharge device 100 performs a painting operation, the maximum vibration frequency component with the largest vibration amplitude is denoted as f. The predetermined relative movement speed of the head 1 by the variable mechanism 2 is denoted as v.

[0069] Nozzle 311-1 is a nozzle included in the nozzle group 360 and is a nozzle predetermined as a reference distance in the main scanning direction A. Nozzle 311-2 is a nozzle located at a distance of v / f from nozzle 311-1 in the main scanning direction A. Nozzle 311-3 is a nozzle located at a distance of 1 / 2 × v / f from nozzle 311-1 in the main scanning direction A. Nozzle 311-4 is a nozzle located at a distance of 3 / 2 × v / f from nozzle 311-1 in the main scanning direction A.

[0070] For example, the distance in the main scanning direction A between two nozzles 311 whose phases align when forming a correction pattern E on the surface S to be painted is (n / 2) × (v / f). Therefore, in this embodiment, the nozzle group selection unit 302 selects the nozzle group 360 such that the distance between the two nozzles 311 in the main scanning direction A is (n / 2) × (v / f). However, in reality, the distance between the nozzles 311 is often not exactly n × (v / f). Therefore, the nozzle group selection unit 302 can select the two nozzles 311 as the nozzle group 360 whose distance in the main scanning direction A is closest to n × (v / f).

[0071] For example, the nozzle group selection unit 302 can select two nozzles 311 to be included in the nozzle group 360: a reference nozzle 311-1 and a nozzle 311-2 that is approximately (v / f) away from nozzle 311-1 in the main scanning direction A, where n=2. However, the nozzle group selection unit 302 may also select nozzle 311-1 and either nozzle 311-3 where n=1, or nozzle 311-4 where n=3, as the two nozzles 311 to be included in the nozzle group 360.

[0072] The control unit 3 moves the head 1 relative to the control unit 306, and the head control unit 305 discharges liquid from the nozzle group 360 selected by the nozzle group selection unit 302. This forms a correction pattern E on the surface S to be painted. By forming the correction pattern E using the nozzle group 360 selected by the nozzle group selection unit 302, the phase of displacement in the sub-scanning direction B is aligned between the correction pattern E1 and the correction pattern E2, as shown in Figure 14. As a result, the change in the distance d between the correction pattern E1 and the correction pattern E2, depending on the position in the main scanning direction A, is reduced.

[0073] In Figure 9, the rotation information acquisition unit 303 acquires information regarding the rotation of the head 1 with respect to the rotation axis RC, which is along the normal N of the nozzle plate 321, based on the correction pattern E formed on the surface S to be painted. For example, the rotation information acquisition unit 303 receives an image of the correction pattern E captured by the imaging unit 6 while it is relatively moved in the main scanning direction A by the variable mechanism 2, via the input unit 301. The rotation information acquisition unit 303 processes the input image of the correction pattern E and detects the interval d between correction pattern E1 and correction pattern E2 in the sub-scanning direction B. Based on the interval d and a predetermined distance between nozzle 311-1 and nozzle 311-2 of the nozzle group 360 in the main scanning direction A, the rotation information acquisition unit 303 calculates and acquires information regarding the rotation of the head 1. The rotation information acquisition unit 303 can acquire information regarding the rotation of the head 1 for each relative position of the head 1 in the main scanning direction A.

[0074] As shown in Figure 14, in the correction pattern E, the interval d is almost constant regardless of the position in the main scanning direction A. Therefore, the rotation information acquisition unit 303 can acquire information about the rotation of the head 1 with high accuracy from the interval d. The rotation information acquisition unit 303 passes the acquired information about the rotation of the head 1 to the correction data creation unit 304.

[0075] In Figure 9, the correction data creation unit 304 creates correction data based on information regarding the rotation of the head 1. The correction data creation unit 304 can create correction data based on the interval d at each predetermined teaching position in the main scanning direction A. The correction data creation unit 304 passes the created correction data to the variable mechanism control unit 306.

[0076] The head control unit 305 controls the discharge of liquid from the head 1 by outputting head control information via the output unit 308. The discharge control information is information for controlling the discharge of liquid by the head 1. The head control unit 305 can control the timing of liquid discharge from the nozzle 311, the amount of liquid, the discharge frequency, etc.

[0077] The variable mechanism control unit 306 controls the relative position and orientation of the head 1 with respect to the surface S to be painted by the variable mechanism 2 by outputting variable mechanism control information via the output unit 308. The variable mechanism control information is information for controlling the operation of the variable mechanism 2.

[0078] In this embodiment, the variable mechanism control unit 306 uses correction data to correct the rotation of the head 1, which is moved relative to the variable mechanism 2, and controls the dispensing of liquid from the head 1. Specifically, the variable mechanism control unit 306 changes the posture of the head 1 using correction data to correct the rotation of the head 1 for each position in the main scanning direction A of the head 1, which is moved relative to the variable mechanism 2. The head control unit 305 causes the liquid to be dispensed from the head 1, which is moved relative to the variable mechanism 2.

[0079] The supply control unit 307 controls the supply of liquid to the head 1 by the supply mechanism 4 by outputting supply control information via the output unit. The supply control information is information for controlling the liquid supply by the supply mechanism 4.

[0080] The output unit 308 controls communication with the head 1, the variable mechanism 2, and the supply mechanism 4, respectively, and outputs head control information, variable mechanism control information, and supply control information.

[0081] The control unit 3 may be further configured as a robot control panel that controls the operation of the variable mechanism 2, a discharge control device that controls the discharge of liquid by the head 1, and a PC that controls the entire system. For example, the robot control panel has the functions of the nozzle group selection unit 302, the rotation information acquisition unit 303, the correction data creation unit 304, and the variable mechanism control unit 306 in Figure 9. The discharge control device has the functions of the head control unit 305 and the supply control unit 307 in Figure 9. The PC has the function of controlling the robot control panel and the discharge control device in an integrated manner.

[0082] The robot control panel and the discharge control device are connected by wire or wireless means, and are configured to output information held by the robot control panel to the discharge control device. The PC generates a robot program to control the robot control panel and transmits it to the robot control panel before painting begins. The PC also generates painting data to control the discharge control device and transmits it to the discharge control device before painting begins. The pavement data may include correction data created by the correction data creation unit 304. When the PC detects the start of painting in response to operator input, it instructs the robot control panel to start executing the robot program. The liquid discharge device 100 can paint the surface to be painted S by controlling the discharge from the head 1 via the discharge control device in synchronization with the operation of the variable mechanism 2 as a robot.

[0083] Robot programming languages ​​are developed by each robot manufacturer. Robot operators can create programs tailored to the specific robot they are using. An example of a robot programming language input into a robot control panel is shown below. MOVJ X=100 Y=50 Z=0 α=0 β=45 γ=30 This command moves head 1 to X=100, Y=50, and Z=0 in each axis. α, β, and γ indicate the angles of head 1. MOVL X=200 Y=80 Z=11 α=0 β=30 γ=0 This command moves head 1 to X=200 Y=80 Z=11 using linear interpolation. α, β, and γ indicate the angles of head 1.

[0084] <Operation of liquid dispensing device 100> Figure 15 is a flowchart showing the operation of the liquid dispensing device 100. Figure 15 shows an example of the operation of the liquid dispensing device 100 to create correction data. In the example shown in Figure 15, the liquid dispensing device 100 starts the operation shown in Figure 15 when it receives a start operation for the correction data creation operation from the operator of the liquid dispensing device 100 via the control unit.

[0085] First, in step S11, the liquid dispensing device 100 uses the vibration detection unit 5 to detect the vibration frequency of the head 1 during the painting operation. The liquid dispensing device 100 uses the variable mechanism 2 to move the head 1 relative to itself, similar to when the head 1 is moved relative to itself during the painting operation, and detects the vibration of the head 1 during the relative movement. The vibration detection unit 5 outputs the detection results to the control unit 3 sequentially or all at once. After the vibration detection by the vibration detection unit 5 is completed, the liquid dispensing device 100 returns the head 1 to its initial position.

[0086] Next, in step S12, the liquid discharge device 100, using the nozzle group selection unit 302, selects a group of nozzles 360 from among the multiple nozzles 311 of the head 1 to be used when forming the correction pattern E. The nozzle group selection unit 302 then passes information regarding the selected nozzle group 360 to the head control unit 305.

[0087] Next, in step S13, the liquid dispensing device 100 dispensing liquid from the nozzle group 360 selected by the nozzle group selection unit 302 while relatively moving the head 1 in the main scanning direction A by the variable mechanism 2. As a result, a correction pattern E is formed on the surface S to be painted.

[0088] Next, in step S14, the liquid dispensing device 100 moves the imaging unit 6 relative to the main scanning direction A by the variable mechanism 2, and the imaging unit 6 captures the correction pattern E.

[0089] Steps S13 and S14 may be performed in parallel. That is, the liquid discharge from the head 1 and the imaging unit 6 may capture the correction pattern E in parallel. For example, the liquid discharge device 100 may use the variable mechanism 2 to move the head 1 and the imaging unit 6 relative to each other in the main scanning direction A, while discharging liquid from the head 1 to form a correction pattern E on the surface to be painted S, and simultaneously capturing the correction pattern E formed on the surface to be painted S with the imaging unit 6.

[0090] From the viewpoint of reducing the number of times the head 1 and the imaging unit 6 are moved relative to each other in the main scanning direction A, it is preferable that the liquid discharge from the head 1 and the imaging unit 6 capture the correction pattern E in parallel. The imaging unit 6 passes the captured image of the correction pattern E to the rotation information acquisition unit 303.

[0091] Next, in step S15, the liquid dispensing device 100, based on the image of the correction pattern E captured by the imaging unit 6, uses the rotation information acquisition unit 303 to acquire information regarding the rotation of the head 1 with respect to the rotation axis RC along the normal N of the nozzle plate 321 as the center of rotation for each predetermined teaching position in the main scanning direction A. The rotation information acquisition unit 303 then passes the acquired information regarding the rotation of the head 1 to the correction data creation unit 304.

[0092] Next, in step S16, the liquid dispensing device 100 creates correction data using the correction data creation unit 304 based on the rotation information of the head 1 acquired by the rotation information acquisition unit 303. The correction data creation unit 304 then passes the created correction data to the variable mechanism control unit 306.

[0093] Next, in step S17, the liquid dispensing device 100 performs painting while correcting using the correction data in order to verify whether or not the unevenness of the paint is reduced by the correction using the correction data.

[0094] Next, in step S18, the liquid dispensing device 100 determines whether or not the unevenness of the paint has been reduced. For example, the operator of the liquid dispensing device 100 visually inspects the paint result in step S17 to determine whether or not the unevenness of the paint has been reduced. The liquid dispensing device 100 receives the determination result from the operator via the control unit and determines whether or not the unevenness of the paint has been reduced.

[0095] If it is determined in step S18 that the level has not been reduced (step S18, NO), the liquid dispensing device 100 repeats the operations from step S11 onward until it is determined in step S18 that the level has been reduced. On the other hand, if it is determined in step S18 that the level has been reduced (step S18, YES), the liquid dispensing device 100 terminates its operation.

[0096] In this manner, the liquid dispensing device 100 can generate correction data.

[0097] This section explains the timing of the operation of the liquid dispensing device 100 shown in Figure 15 (hereinafter referred to as "rotational attitude deviation correction"), that is, what triggers the operation of the liquid dispensing device 100 shown in Figure 15.

[0098] "Rotational orientation deviation correction" is performed during the painting preparation phase. Painting preparation refers to the preparatory operations performed before the main painting, which is separate from the so-called "main painting" where painting operations are repeatedly performed on a large number of objects that will become products on a production line. Painting preparation begins with selecting the objects to be painted, and then determining the control methods for the variable mechanism, head, and supply mechanism according to the objects to be painted. These control methods are designed according to the specifications of the variable mechanism, head, and supply mechanism, and are mainly performed on a desk. Next, the determined control methods are implemented on the actual machine, and the difference between the desk and the actual machine is checked to confirm that the desired operation is achieved, and adjustments are made as needed. "Rotational orientation deviation correction" is one of these confirmation and adjustment operations. Next, test painting and quality checks are performed to confirm that the desired paint finish has been achieved, and the painting operation is completed. If the desired paint finish has not been achieved, the control methods and other aspects are reviewed again.

[0099] The painting process is completed by performing the painting preparation, and the actual painting process repeats the painting process completed during the preparation. During this process, no adjustments or control methods are considered; the painting process is basically repeated. In other words, rotational attitude deviation correction is performed during the painting preparation before the actual painting, and not each time the actual painting is performed.

[0100] It is known that the painting operation determined by the painting preparation process can gradually develop errors in the variable mechanism, head, supply mechanism itself, or control system due to repeated painting operations and over time. Therefore, depending on the object being painted and the frequency, it is necessary to repeat certain painting preparation processes at regular intervals, for example, once every few months. The same applies to rotational attitude deviation correction, which should be performed at a frequency of, for example, once every few months.

[0101] Referring to Figures 16A to 16C, the mechanism by which the rotation of the head 1 in the liquid dispensing device 100 is corrected in response to relative movement in the main scanning direction A will be explained. Figure 16A shows the rotation of the head 1 in the liquid dispensing device 100 in response to relative movement in the main scanning direction A. Figure 16B shows the change in the posture of the head 1 that corrects the rotation of the head 1 in the liquid dispensing device 100 in response to relative movement in the main scanning direction A. Figure 16C shows the mechanism by which the rotation of the head 1 in the liquid dispensing device 100 is corrected in response to relative movement in the main scanning direction A. The head 1 shown in Figures 16A to 16C is shown as viewed from the nozzle surface 350 side.

[0102] As shown in Figure 16A, when the head 1 is moved in the main scanning direction A by the variable mechanism 2, the head 1 rotates around the rotation axis RC as the center of rotation. The head 1 discharges liquid from the nozzle group 360 selected by the nozzle group selection unit 302 to form a correction pattern E. The liquid discharge device 100 determines the rotation angle θ1 using the predetermined ideal interval d of the correction pattern E and the detection result interval d1. The liquid discharge device 100 also determines the rotation angle θ2 using the ideal interval d and the detection result interval d2.

[0103] As shown in Figure 16B, the liquid dispensing device 100 creates correction data to change the posture of the head 1 so that the rotation angles θ1 and θ2 are reduced for each predetermined teaching position in the main scanning direction A. For example, the correction data is such that at a teaching position where the head 1 rotates by an angle θ1, the posture of the head 1 is changed so that the head 1 rotates by -θ1. Also, at a teaching position where the head 1 rotates by an angle θ2, the correction data is such that the posture of the head 1 is changed so that the head 1 rotates by -θ2.

[0104] By changing the orientation of head 1 according to the correction data, the rotation angles θ1 and θ2 of head 1 are reduced, for example, as shown in Figure 16C. In Figure 16C, the dashed line representing head 1W shows head 1 in its rotated state before the orientation change.

[0105] <Effects and Effects of Liquid Dispensing Device 100> As described above, in this embodiment, the control unit 3 uses a group of nozzles 360 selected from a plurality of nozzles 311 based on the maximum vibration frequency component f with the largest vibration amplitude among a plurality of vibration frequency components included in the vibrations generated in at least one of the head 1 and the variable mechanism 2 when the liquid discharge device 100 performs a painting operation, and the predetermined relative movement speed v of the head 1 by the variable mechanism 2, to form a correction pattern E on the surface to be painted S.

[0106] The control unit 3 acquires information regarding the rotation of the head 1 with respect to the rotation axis RC, which is aligned with the normal N of the nozzle plate 321, based on a correction pattern E formed on the surface S to be painted. Based on the rotation information, the control unit 3 corrects the rotation of the head 1, which is moved relative to the variable mechanism 2, and controls the head 1 to discharge liquid. By selecting the nozzle group 360, the effect of vibration of the head 1 can be reduced, and the rotation of the head 1 can be corrected with high precision. As a result, the painting accuracy can be improved in this embodiment.

[0107] The liquid dispensing device 100 has a vibration detection unit 5. The control unit 3 selects a group of nozzles 360 based on the maximum vibration frequency component f with the largest vibration amplitude among the multiple vibration frequency components included in the vibration detected by the vibration detection unit 5, and a predetermined relative movement speed v of the head 1 by the variable mechanism 2. By using the detection results from the vibration detection unit 5, a group of nozzles 360 can be appropriately selected to reduce the influence of vibrations from at least one of the head 1 and the variable mechanism 2.

[0108] The control unit 3 selects a group of nozzles 360 in which the phase of the displacement of the correction pattern E in the sub-scanning direction B, corresponding to the relative movement of the head 1 in the main scanning direction A, is aligned. As a result, the liquid discharge device 100 can reduce the influence of vibrations from at least one of the head 1 and the variable mechanism 2, and accurately correct the rotation of the head 1 in response to its relative movement in the main scanning direction A.

[0109] For example, the control unit 3 uses a group of nozzles 360 selected such that the distance between the nozzles 311 in the main scanning direction A is (n / 2) × (v / f) to form a correction pattern E on the surface to be painted S. Based on the correction pattern E, the control unit 3 changes the posture of the head 1 using the variable mechanism 2 at each predetermined teaching position in the main scanning direction A. As a result, the liquid discharge device 100 can reduce the influence of vibrations of at least one of the head 1 and the variable mechanism 2, and accurately correct the rotation of the head 1 in response to its relative movement in the main scanning direction A.

[0110] [Second Embodiment] Next, a liquid dispensing device according to the second embodiment will be described. Note that names and reference numerals identical to those used in the previously described embodiments indicate the same or identical components or configurations, and detailed explanations will be omitted as appropriate. This also applies to the embodiments described later.

[0111] <Configuration of the liquid dispensing device according to the second embodiment> Figure 17 is a block diagram showing the configuration of the liquid dispensing device 100a according to the second embodiment.

[0112] As shown in Figure 17A, in this embodiment, the liquid dispensing device 100a has a bending detection unit 7 that detects the amount of bending of the liquid discharged from the head 1. The control unit 3 corrects the rotation of the head 1, which is moved relative to it by the variable mechanism 2, based on the amount of bending detected by the bending detection unit 7. This point differs from the liquid dispensing device 100 according to the first embodiment.

[0113] For the method of detecting discharge curvature by the curvature detection unit 7, for example, the method described in Japanese Patent Application Publication No. 2024-92320 can be used. In the method described in Japanese Patent Application Publication No. 2024-92320, a liquid is discharged onto a predetermined medium, the liquid applied to the medium is imaged with a camera, and discharge curvature is detected based on the position and size of the liquid. The contents disclosed in Japanese Patent Application Publication No. 2024-92320 are incorporated into this specification by reference. Hereinafter, the coating system 10000 will be described as an example of a liquid discharge device according to the second embodiment, in accordance with the contents described in Japanese Patent Application Publication No. 2024-92320.

[0114] Figure 17B is a schematic diagram showing the configuration of the painting system 10000. The painting system 10000 includes a maintenance station 2000 within reach of the painting robot 1000. The maintenance station 2000 includes a maintenance and cleaning unit 2001, and the head 100 is moved to the maintenance and cleaning unit 2001 by the painting robot 1000 before painting, at the end of painting, or when a specified time has elapsed for painting.

[0115] The maintenance and cleaning unit 2001 is equipped with maintenance devices such as a cleaning mechanism that performs wiping cleaning on the nozzle surface of the head 100, and a storage unit (empty discharge receiver) for receiving paint discharged from the nozzle when the head 100 is subjected to empty discharge.

[0116] Furthermore, the maintenance and cleaning unit 2001 is equipped with a media plate that holds a test pattern formed by the discharge operation of all nozzles of the head 100 before painting or when the painting time has elapsed. The media plate will be described later.

[0117] Furthermore, the maintenance and cleaning unit 2001 is equipped with a cleaning device that sprays cleaning fluid or cleaning air onto the nozzle surface of the head 100 to clean the nozzle surface, and a cleaning device that sprays cleaning fluid or cleaning air onto the media plate to remove test patterns from the media plate.

[0118] In this embodiment, the painting system 10000 is configured with one painting robot 1000 installed on each side of the vehicle body U, but it is not limited to this configuration. The number of painting robots can be determined appropriately based on the painting area of ​​the vehicle body U, work efficiency, etc., and there may be one painting robot or three or more painting robots in the painting system 10000.

[0119] Furthermore, if there are multiple painting robots 1000, the maintenance station 2000 may be shared by multiple painting robots, or one may be installed for each painting robot. The maintenance station 2000 is installed at a distance from the vehicle body U to prevent paint discharged from the nozzle by the aforementioned dry discharge, as well as cleaning fluid used when cleaning the nozzle surface and media plate, from adhering to the vehicle body U.

[0120] <Example of media board configuration> Figure 17C shows the configuration of the media board. The maintenance and cleaning section 2001 of the maintenance station 2000 is equipped with a media board 2002 that holds a test pattern formed by the discharge operation of all nozzles before painting or when the painting time has elapsed.

[0121] The media board 2002 is fixed to the media board support member 2003 with screws or the like. A base plate 2005 is fixed to the frame 2004 of the maintenance station 2000, and a cover member 2006 is attached via this base plate 2005. The media board support member 2003, on which the media board 2002 rests, can reciprocate in the direction of arrow B, and the media board support member 2003 can pass through the inside of the cover member 2006 and exit to the rear side of the base plate 2005. The rear side of the base plate 2005 is equipped with a cleaning mechanism for removing the test pattern formed on the surface of the media board 2002.

[0122] The media plate support member 2003, on which the media plate 2002 has been removed after the test pattern has been removed, moves through the inside of the cover member 2006 and to the front of the base plate 2005 in accordance with the formation of the next test pattern. When forming the test pattern on the media plate 2002, the heads 100 (700, 700A, 700B) are positioned directly above the media plate 2002 as shown by the dashed lines, and in this state, the dispensing operation is performed for all nozzles.

[0123] In the above explanation, the media board 2002 is assumed to be located within the maintenance station 2000, but the media board 2002 may be installed in a location other than the maintenance station 2000.

[0124] <Overview of Test Patterns> Figures 17D and 17E are explanatory diagrams showing examples of test patterns. Figure 17D is a plan view showing an example of a media board on which a test pattern has been formed. Figure 17E is an enlarged view of section P in Figure 17D.

[0125] Figure 17D shows a test pattern formed on a media plate 2002 by multiple nozzle heads. To obtain this test pattern, the heads are moved by a painting robot so that the nozzle surfaces of the multiple nozzle heads face the media plate 2002, and the dispensing operation is performed on all nozzles of the multiple nozzle heads. If all nozzles of the multiple nozzle heads are functioning correctly, a test pattern TPA as shown in Figure 17D is obtained.

[0126] Next, the painting robot rotates the head holding member by 90 degrees so that the nozzle surfaces of the multiple nozzle heads face the area of ​​the media board 2002 where the test pattern TPA is not formed. Then, the dispensing operation is performed on all the nozzles of the multiple nozzle heads. If all the nozzles of the multiple nozzle heads are functioning correctly, the test pattern TPB shown in Figures 17D and 17E is obtained.

[0127] <Operation of liquid dispensing device 100a> Figure 18 is a flowchart showing the operation of the liquid dispensing device 100a. Parts similar to the liquid dispensing device 100 according to the first embodiment shown in Figure 15 are omitted for brevity, and only the differences are explained.

[0128] As shown in Figure 18, in step S23, the liquid dispensing device 100a detects the amount of bending of the liquid discharged from the head 1 using the bending detection unit 7. The bending detection unit 7 outputs the result of the bending amount detection to the control unit 3.

[0129] In step S27, the liquid dispensing device 100a uses the correction data creation unit 304 to create correction data that changes the posture of the head 1 so as to reduce the rotation of the head 1, which is moved relative to the variable mechanism 2, based on the amount of bending detected by the bending detection unit 7. By changing the posture of the head 1 using the created correction data, the liquid dispensing device 100a can reduce the rotation of the head 1 in accordance with the relative movement in the main scanning direction A.

[0130] The timing of the operation of the liquid dispensing device 100 shown in Figure 18, that is, what triggers the operation of the liquid dispensing device 100 shown in Figure 18, is the same as the operation of the liquid dispensing device 100 shown in Figure 15.

[0131] <Effects and Effects of Liquid Dispensing Device 100a> For example, if the discharge direction of the liquid discharged from head 1 deviates from a predetermined direction, the correction pattern E cannot be accurately formed, and appropriate correction data cannot be created. In this embodiment, the bending detection unit 7 detects the amount of bending of the liquid discharged from head 1, and correction data is created taking the detected amount of bending into account. This reduces the effect of bending in the liquid discharge and makes it possible to create appropriate correction data. In this embodiment, the painting accuracy can be improved by correcting the rotation of head 1 using appropriate correction data. The effects and advantages of this embodiment other than those described above are the same as those of the first embodiment.

[0132] [Third Embodiment] Next, a liquid dispensing device according to the third embodiment will be described with reference to Figures 19 and 20. Figure 19 is a block diagram showing the functional configuration of the control unit 3 in the liquid dispensing device 100b according to the third embodiment. Figure 20 is a diagram illustrating how the liquid dispensing device 100b detects vibration amplitude. Note that the head 1 shown in Figure 20 is the head 1 as seen from the nozzle surface 350 side.

[0133] As shown in Figure 19, the liquid dispensing device 100b according to this embodiment differs from the liquid dispensing device 100 according to the first embodiment in that the control unit 3 has an amplitude information acquisition unit 309. The amplitude information acquisition unit 309 detects the amplitude of the displacement of the correction pattern E in the sub-scanning direction B in accordance with the relative movement of the head 1 in the main scanning direction A by the variable mechanism 2.

[0134] The amplitude information acquisition unit 309 acquires information regarding the amplitude of the displacement of the correction pattern E in the sub-scanning direction B, based on the correction pattern E formed by the liquid discharged from each of the two nozzles 311 included in the nozzle group 360.

[0135] The control unit 3 forms a correction pattern E on the surface to be painted S using a group of nozzles 360 selected such that the distance between nozzles 311 in the main scanning direction A is {(2n-1) / 2} × (v / f). For each predetermined teaching position in the main scanning direction A, the control unit 3 creates correction data based on the interval d of the correction pattern E in the sub-scanning direction B.

[0136] For example, the liquid dispensing device 100 selects the nozzle group 360 such that the distance between the nozzles 311 in the main scanning direction A, where the displacement of the correction pattern E in the sub-scanning direction B is in phase, is closest to (n / 2) × (v / f). As a result, the displacement of the correction pattern E in the sub-scanning direction B is in phase or out of phase between the correction pattern E1 and the correction pattern E2.

[0137] As shown in Figure 20, the correction pattern E includes correction pattern E1 and correction pattern E2 formed by two nozzles 311 included in the nozzle group 360. In the example shown in Figure 20, the phase of the displacement in the sub-scanning direction B in correction pattern E1 and the phase of the displacement in the sub-scanning direction B in correction pattern E2 are shifted by half a cycle and are in opposite phases.

[0138] The minimum interval between correction pattern E1 and correction pattern E2 in the sub-scanning direction B is defined as the minimum interval dmin, and the maximum interval is defined as the maximum interval dmax. The amplitude information acquisition unit 309 can acquire the amplitude G of the displacement of correction pattern E in the sub-scanning direction B by calculation using the following equation. G = (dmax - dmin) / 4

[0139] <Effects and Effects of Liquid Dispensing Device 100b> In this embodiment, the amplitude G acquired by the amplitude information acquisition unit 309 can be used, for example, to verify the vibration reduction effect in the liquid dispensing device 100b. Specifically, the smaller the amplitude G, the greater the vibration reduction effect in the liquid dispensing device 100b. Therefore, in the liquid dispensing device 100b, the vibration reduction effect can be verified, for example, by determining whether the amplitude G acquired by the amplitude information acquisition unit 309 is smaller than a predetermined amplitude threshold.

[0140] Furthermore, the control unit 3 can also calculate the displacement of the nozzle 311 due to the rotation of the head 1 by calculating (dmax + dmin) / 2. The effects and advantages of this embodiment other than those described above are the same as those of the first embodiment.

[0141] [Fourth Embodiment] Next, a liquid dispensing device according to the fourth embodiment will be described.

[0142] In this embodiment, the liquid dispensing device differs from the liquid dispensing device 100b in the third embodiment in that the control unit 3 acquires information regarding the shift of the head 1 in the sub-scanning direction B corresponding to the relative movement in the main scanning direction A, based on a correction pattern E formed by the liquid dispensed from each of the two nozzles 311 included in the nozzle group 360.

[0143] Figure 21 illustrates the shift of head 1 in the sub-scanning direction B. In Figure 21, the ideal path IP represents the ideal relative movement path of head 1 in the main scanning direction A. The teaching position TP represents the point for teaching the position that head 1 will pass through in the main scanning direction A to the variable mechanism 2. Note that the head 1 shown in Figure 21 is shown as viewed from the nozzle surface 350 side.

[0144] In the example shown in Figure 21, head 1 shifts in the sub-scanning direction B while moving in the main scanning direction A. Also, head 1 is not rotating around the rotation axis RC as its center of rotation. By shifting in the sub-scanning direction B in response to its relative movement in the main scanning direction A, head 1 meanders during its relative movement in the main scanning direction A. The meandering path SP represents the path that head 1 takes as it meanders during its relative movement due to its shift in the sub-scanning direction B.

[0145] Here, we will explain the difference between the case where head 1 vibrates as described with reference to Figure 12 when moving relative to the main scanning direction A, and the case where it meanders as shown in the meandering path SP in Figure 21. Vibration when head 1 moves relative to the main scanning direction A refers to the repeated periodic displacement of head 1 in the sub-scanning direction multiple times from the start to the end of a single relative movement in the main scanning direction A. On the other hand, meandering when head 1 moves relative to the main scanning direction A refers to the aperiodic displacement of head 1 approximately once in the sub-scanning direction from the start to the end of a single relative movement in the main scanning direction A.

[0146] Figure 22 is a block diagram showing the functional configuration of the control unit 3 in the liquid dispensing device according to the fourth embodiment. The control unit 3 differs from the control unit 3 in the liquid dispensing device 100 according to the first embodiment in that it has a shift information acquisition unit 310.

[0147] The shift information acquisition unit 310 acquires information regarding the shift of the head 1 in the sub-scanning direction B corresponding to the relative movement in the main scanning direction A, based on a correction pattern E formed by the liquid discharged from each of the two nozzles 311 included in the nozzle group 360. The shift information acquisition unit 310 passes the acquired shift information to the correction data creation unit 304.

[0148] Figure 23 shows an image Im of the correction pattern E in a liquid dispensing device according to the fourth embodiment. Figure 23 shows an image Im of the correction pattern E formed on a surface to be painted, captured by the imaging unit 6 shown in Figure 2. The shift information acquisition unit 310 can, for example, acquire the image Im as information about the shift and pass it to the correction data creation unit 304.

[0149] In the example shown in Figure 23, the correction pattern E includes a correction pattern E1 formed from liquid discharged from one of the two nozzles 311 included in the nozzle group 360, and a correction pattern E2 formed from liquid discharged from the other nozzle.

[0150] The procedure involves first printing the detection pattern through a continuous operation as usual. Next, a step operation is performed, stopping sequentially at each teaching point. When the head 1 reaches each teaching point, the position of the detection pattern is measured using the imaging unit 6 attached to the head 1 or various sensors. Figure 24 is a schematic diagram illustrating the configuration and arrangement of the imaging unit 6. Figure 24 shows the configuration of the imaging unit 6 and its arrangement during painting and measurement.

[0151] It is desirable to measure at the position of head 1 during stepping at the same teaching point as the painting operation. If it is difficult to capture the detection pattern with the same operation due to the shooting range of the sensor and imaging unit 6, or mounting constraints, a method such as moving the head to the teaching point during measurement, which is shifted by a fixed amount (same direction and amount) from the teaching point during painting, as shown in Figure 24, and taking a photograph can be selected.

[0152] In this embodiment, the distance between two nozzles 311 included in the nozzle group 360 in the main scanning direction A is (2n-1) / 2) × (v / f). As a result, in correction pattern E1 and correction pattern E2, the phase of the displacement in the sub-scanning direction B corresponding to the relative movement of head 1 in the main scanning direction A is in opposite phase. The maximum interval dmax is the maximum interval between correction pattern E1 and correction pattern E2 in the sub-scanning direction B. The minimum interval dmin is the minimum interval between correction pattern E1 and correction pattern E2 in the sub-scanning direction B. The center line CL is the line passing through the center of the above displacement in correction pattern E1.

[0153] The correction data creation unit 304 can create correction data to correct the shift of the head 1 in the sub-scanning direction B corresponding to the relative movement in the main scanning direction A. For example, for each teaching position TP, the correction data creation unit 304 creates correction data to move the head 1 in the opposite direction to the shift by approximately the same relative movement amount as the shift, so as to reduce the shift of the head 1. Based on the correction data, the liquid discharge device of the fourth embodiment moves the head 1 in the opposite direction to the shift by approximately the same relative movement amount as the shift for each teaching position TP. This corrects the shift of the head 1 and allows the head 1 to move relatively along a path close to the ideal path IP shown in Figure 21. As a result, in this embodiment, uneven coating can be reduced and coating accuracy can be improved. Other effects and advantages in this embodiment are the same as those in the first embodiment.

[0154] <Simulation methods using big data> By analyzing big data, which is an enormous amount of data that cannot be handled by conventional databases, it becomes possible to create new value in various fields. The benefits of utilizing big data include more accurate decision-making, discovery of new business opportunities, improved operational efficiency, and increased customer satisfaction. By performing simulations using big data, it becomes possible to more accurately predict phenomena that were previously difficult to predict and to analyze the behavior of complex systems in detail. The painting operation and performance of the liquid discharge device according to each of the first to fourth embodiments can be simulated using big data. Below is an example of how to perform simulations from big data such as shape data and correction data in each embodiment.

[0155] (1) Data collection and preprocessing Identify data sources from which the necessary data can be collected and then collect the data. As a preprocessing step for the collected data, perform data cleaning (remove missing values, outliers, noise, etc.). Data cleaning improves the quality of the data, standardizes the data format to make it easier to analyze, and allows for the extraction and creation of effective features for analysis. At this stage, artificial intelligence (AI) techniques such as machine learning or deep learning can also be used to extract deeper features from the data.

[0156] (2) Model selection Select an appropriate model according to the purpose of the simulation, set the parameters of the selected model appropriately, and verify the accuracy of the model using historical data.

[0157] (3) Running the simulation We will build an environment for running simulations and execute simulations using the built model. The simulation results will then be visualized using graphs, diagrams, etc. By applying simulations using big data such as shape data and correction data in each embodiment, high-precision correction can be achieved for the rotation of head 1.

[0158] <Digital Twin> A digital twin, which connects the real world and virtual space, is a technology that reproduces real-world objects in a virtual space and simulates their behavior, enabling prediction or optimization of the real world. Simulation is the heart of a digital twin and is a crucial tool for conducting various experiments and analyses in the virtual space based on real-world data. Simulation data quantifies and models complex phenomena in the real world, bringing benefits such as improved prediction accuracy, optimization, risk reduction, and cost reduction. Digital twins are expected to become even more sophisticated through integration with AI or IoT (Internet of Things). For example, machine learning can be used to improve simulation accuracy, or edge computing can be utilized to realize real-time simulations.

[0159] An example of how to apply simulation data from each embodiment to a digital twin is shown below.

[0160] (1) Preprocessing of simulation data Data cleaning is performed to improve the quality of the collected simulation data by processing noise or missing values. Data conversion is performed to convert the cleaned simulation data into a format that can be used by the simulation model.

[0161] (2) Construction of a simulation model Construct a model that describes the physical properties of the object being simulated. Construct a mathematical model that expresses the constructed physical model using mathematical equations. Develop an algorithm to numerically solve the constructed mathematical model.

[0162] (3) Integration into a digital twin The simulation results are displayed in a visually easy-to-understand format, such as a 3D model or graph, to visualize the simulation results. The visualized simulation results are compared with real-world measurement data, sensor data, and other data to verify the accuracy of the model. Based on the simulation results, the accuracy of the verified model is improved by adjusting the real-world control parameters.

[0163] By applying the simulation data from each embodiment to a digital twin, it becomes possible to simulate the correction for the rotation of head 1 used when painting a surface to be painted. Furthermore, this principle can be applied to simulate heads installed in various printers.

[0164] Although preferred embodiments have been described in detail above, the invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the claims.

[0165] The ordinal numbers, quantities, and other figures used in the description of the embodiments are all illustrative to specifically illustrate the technology of the present invention, and the present invention is not limited to these illustrative figures. Furthermore, the connection relationships between the components are illustrative to specifically illustrate the technology of the present invention, and do not limit the connection relationships that realize the functions of the present invention.

[0166] The division of blocks in the functional block diagram is just one example; multiple blocks may be implemented as a single block, one block may be divided into multiple parts, or some functions may be moved to other blocks. Furthermore, the functions of multiple blocks with similar functions may be processed in parallel or time-sharing by a single piece of hardware or software. Also, some or all of the functions may be distributed across multiple computers.

[0167] In the embodiment, the liquid discharged from head 1 may be a solution, suspension, emulsion, etc., containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a functional material such as a surfactant, a biocompatible material such as DNA, amino acids or proteins, calcium, or an edible material such as a natural pigment. These can be used, for example, as inkjet inks, coatings, surface treatment liquids, components for electronic elements and light-emitting elements, liquids for forming electronic circuit resist patterns, and material liquids for 3D modeling.

[0168] The surface to be painted S refers to anything to which liquid adheres and solidifies, or adheres and penetrates. Specific examples include car bodies, building materials, paper, recording paper, film, cloth and other recording media, electronic components such as electronic circuit boards and piezoelectric elements, powder layers, organ models, inspection cells, and other media. Unless otherwise specified, it includes everything to which liquid adheres.

[0169] Each function of the embodiment can be realized by one or more processing circuits. Hereinafter, "processing circuit" as used herein includes processors programmed to execute each function by software, such as processors implemented by electronic circuits, as well as devices such as ASICs (Application Specific Integrated Circuits), DSPs (Digital Signal Processors), FPGAs (Field Programmable Gate Arrays), and conventional circuit modules designed to execute the functions described above.

[0170] Examples of the present invention are as follows: <1> A liquid dispensing device for dispensing liquid to paint a surface to be painted, comprising: a head including a nozzle plate, which individually dispenses liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate; a variable mechanism for changing the relative position and relative orientation of the head with respect to the surface to be painted; and a control unit for controlling the operation of the head and the variable mechanism, respectively, wherein the control unit uses a group of nozzles selected from the plurality of nozzles based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and a predetermined relative movement speed of the head by the variable mechanism to form a correction pattern on the surface to be painted, and based on the correction pattern formed on the surface to be painted, information regarding the rotation of the head with a rotation axis along the normal to the nozzle plate as the center of rotation, and based on the rotation information, corrects the rotation of the head which is moved relative to the variable mechanism, and controls the dispensing of the liquid from the head. <2> The liquid dispensing device has a vibration detection unit that detects vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and the control unit selects the nozzle group based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibration detected by the vibration detection unit and a predetermined relative movement speed of the head by the variable mechanism, <1> This is the liquid dispensing device described in [reference]. <3> The control unit selects from the plurality of nozzles a group of nozzles in which the phase of the displacement of the correction pattern in the sub-scanning direction perpendicular to the main scanning direction, corresponding to the relative movement of the head in the main scanning direction by the variable mechanism, is aligned. <1> or the above <2> This is the liquid dispensing device described in [reference]. <4> The control unit has a bending detection unit that detects the amount of bending of the liquid discharged from the head, and the control unit further corrects the rotation of the head which is moved relative to the variable mechanism based on the amount of bending detected by the bending detection unit. <1> from the above <3> It is a liquid dispensing device as described in any one of the following. <5> The control unit, with n being an integer, f being the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid discharge device performs a painting operation, and v being a predetermined relative movement speed of the head by the variable mechanism, uses a group of nozzles selected such that the distance between the plurality of nozzles in the main scanning direction is (n / 2) × (v / f) to form the correction pattern on the surface to be painted, and creates the correction data based on the correction pattern for each predetermined teaching position in the main scanning direction where the variable mechanism changes the posture of the head. <1> from the above <4> It is a liquid dispensing device as described in any one of the following. <6> The control unit uses a group of nozzles selected such that the distance between the multiple nozzles in the main scanning direction is {(2n-1) / 2}×(v / f), where n is an integer, f is the maximum vibration frequency component with the largest vibration amplitude among the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid discharge device performs a painting operation, and v is a predetermined relative movement speed of the head by the variable mechanism, to form the correction pattern on the surface to be painted, and creates the correction data based on the correction pattern for each predetermined teaching position in the main scanning direction where the variable mechanism changes the posture of the head. <1> from the above <5> It is a liquid dispensing device as described in any one of the following. <7> The control unit acquires information regarding the amplitude of the displacement of the correction pattern in the sub-scanning direction perpendicular to the main scanning direction, based on the correction pattern formed by the liquid discharged from each of the two nozzles included in the nozzle group. <6> This is the liquid dispensing device described in [reference]. <8> The control unit acquires information regarding the shift of the head in a sub-scanning direction perpendicular to the main scanning direction, corresponding to the relative movement in the main scanning direction, based on the correction pattern formed by the liquid discharged from each of the two nozzles included in the nozzle group. <6> This is the liquid dispensing device described in [reference]. <9> A liquid dispensing method using a liquid dispensing device for coating a surface to be painted by dispensing liquid, wherein the liquid dispensing device uses a head including a nozzle plate to individually dispensing liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate, a variable mechanism to change the relative position and orientation of the head with respect to the surface to be painted, a control unit to control the operation of the head and the variable mechanism respectively, the control unit uses a group of nozzles selected from the plurality of nozzles based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibration generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and a predetermined relative movement speed of the head by the variable mechanism to form a correction pattern on the surface to be painted, obtains information on the rotation of the head with a rotation axis along the normal of the nozzle plate as the center of rotation based on the correction pattern formed on the surface to be painted, corrects the rotation of the head which is moved relative to the variable mechanism based on the rotation information, and controls the dispensing of the liquid from the head. <10> A program that operates in a liquid dispensing device that dispenses liquid to paint a surface to be painted, wherein a head including a nozzle plate dispenses liquid individually from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate, a variable mechanism changes the relative position and orientation of the head with respect to the surface to be painted, a control unit controls the operation of the head and the variable mechanism respectively, the control unit uses a group of nozzles selected from the plurality of nozzles based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, and a predetermined relative movement speed of the head by the variable mechanism to form a correction pattern on the surface to be painted, obtains information on the rotation of the head with a rotation axis along the normal of the nozzle plate as the center of rotation based on the correction pattern formed on the surface to be painted, and corrects the rotation of the head which is moved relative to the head by the variable mechanism based on the rotation information to control the dispensing of the liquid from the head. [Explanation of Symbols]

[0171] 1, 1Y, 1M, 1C, 1K, 1W Head 2 Variable mechanism 3. Control Unit 4 Supply mechanism 5. Vibration detection unit 6. Imaging Unit 7. Bending detection unit 31 CPU 32 ROM 33 RAM 34 HDD / SSD 35. Device Connection Interface 36 Communication I / F 100, 100a, 100b liquid dispensing device 110 Housing 111 supply ports 112 Recovery Port 113 Connector 230 Compressor 301 Input section 302 Nozzle group selection unit 303 Rotation Information Acquisition Unit 304 Correction Data Creation Section 305 Head Control Unit 306 Variable Mechanism Control Unit 307 Supply Control Unit 308 Output section 309 Amplitude information acquisition section 310 Shift Information Acquisition Unit 311, 311-1, 311-2, 311-3, 311-4 nozzles 321 Nozzle Plate 322 Flow Channel 324 Piezoelectric element 325 Liquid 330, 330Y, 330M, 330C, 330K liquid tanks 331 Pipe 332 Air Regulator 333 Tube 340 Discharge Module 350 nozzle surface 351 nozzle rows 360 nozzle group A Main scanning direction B Sub-scanning direction CL center line d, d1, d2, d3 spacing dmax maximum interval dmin minimum interval E, E1, E2 Correction Patterns f is the maximum vibration frequency component. G amplitude IP Ideal Path L, L1, L2, L3, L4 Linear Patterns N normal P position signal RC rotation axis SB System Bus SD Shape Data SP meandering path T1 Synchronization signal T2 Interval Signal T3 discharge signal Td delay time Tout Dispensing time TP teaching position v Relative movement speed θ1, θ2 Rotation angle [Prior art documents] [Patent Documents]

[0172] [Patent Document 1] Patent No. 7521360

Claims

1. A liquid dispensing device that dispenses liquid to paint a surface to be painted, A head including a nozzle plate, which individually discharges liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate, A variable mechanism for changing the relative position and relative orientation of the head with respect to the surface to be painted, It includes a control unit that controls the operation of the head and the variable mechanism, respectively. The control unit, Of the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, the maximum vibration frequency component with the largest vibration amplitude, Based on the predetermined relative movement speed of the head by the variable mechanism, a group of nozzles selected from the plurality of nozzles is used to form a correction pattern on the surface to be painted. Based on the correction pattern formed on the surface to be painted, information regarding the rotation of the head is obtained with the rotation axis along the normal of the nozzle plate as the center of rotation. A liquid dispensing device that controls the dispensing of the liquid from the head by correcting the rotation of the head, which is moved relative to the head by the variable mechanism, based on information regarding the rotation of the head.

2. The liquid dispensing device has a vibration detection unit that detects vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation. The liquid dispensing device according to claim 1, wherein the control unit selects the nozzle group based on the maximum vibration frequency component with the largest vibration amplitude among a plurality of vibration frequency components included in the vibration detected by the vibration detection unit, and a predetermined relative movement speed of the head by the variable mechanism.

3. The liquid dispensing apparatus according to claim 1 or 2, wherein the control unit selects from among the plurality of nozzles a group of nozzles in which the phase of the displacement of the correction pattern in the sub-scanning direction perpendicular to the main scanning direction, corresponding to the relative movement of the head in the main scanning direction by the variable mechanism, is aligned.

4. It has a bending detection unit that detects the amount of bending of the liquid discharged from the head, The control unit, The liquid dispensing device according to claim 1, further correcting the rotation of the head, which is moved relative to the bend by the variable mechanism, based on the amount of bend detected by the bend detection unit.

5. The control unit, Let n be an integer, When the liquid dispensing device performs a painting operation, let f be the maximum vibration frequency component with the largest vibration amplitude among the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism. If the predetermined relative movement speed v of the head due to the variable mechanism is as follows, Using the group of nozzles selected such that the distance between the nozzles in the main scanning direction is (n / 2) × (v / f), the correction pattern is formed on the surface to be painted. The liquid dispensing device according to claim 1, wherein the attitude of the head is changed by the variable mechanism at each predetermined teaching position in the main scanning direction based on the correction pattern.

6. The control unit, Let n be an integer, When the liquid dispensing device performs a painting operation, let f be the maximum vibration frequency component with the largest vibration amplitude among the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism. If the predetermined relative movement speed v of the head due to the variable mechanism is as follows, Using the group of nozzles selected such that the distance between the nozzles in the main scanning direction is {(2n-1) / 2} × (v / f), the correction pattern is formed on the surface to be painted. The liquid dispensing device according to claim 1, wherein the attitude of the head is changed by the variable mechanism at each predetermined teaching position in the main scanning direction based on the correction pattern.

7. The liquid dispensing apparatus according to claim 6, wherein the control unit acquires information regarding the amplitude of the displacement of the correction pattern in a sub-scanning direction perpendicular to the main scanning direction, based on the correction pattern formed by the liquid discharged from each of the two nozzles included in the nozzle group.

8. The liquid dispensing apparatus according to claim 6, wherein the control unit acquires information regarding the shift of the head in a sub-scanning direction perpendicular to the main scanning direction, corresponding to the relative movement in the main scanning direction, based on the correction pattern formed by the liquid discharged from each of the two nozzles included in the nozzle group.

9. A liquid dispensing method using a liquid dispensing device that dispenses liquid to paint a surface to be painted, The aforementioned liquid dispensing device, The head, including the nozzle plate, individually discharges liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate. The variable mechanism changes the relative position and orientation of the head with respect to the surface to be painted. The control unit controls the operation of the head and the variable mechanism, respectively. The control unit, Of the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, the maximum vibration frequency component with the largest vibration amplitude, Based on the predetermined relative movement speed of the head by the variable mechanism, a group of nozzles selected from the plurality of nozzles is used to form a correction pattern on the surface to be painted. Based on the correction pattern formed on the surface to be painted, information regarding the rotation of the head is obtained with the rotation axis along the normal of the nozzle plate as the center of rotation. A liquid dispensing method that controls the dispensing of the liquid from the head by correcting the rotation of the head, which is moved relative to the head by the variable mechanism, based on information regarding the rotation of the head.

10. A program that operates in a liquid dispensing device that dispenses liquid to paint a surface to be painted, The head, including the nozzle plate, individually discharges liquid from a plurality of nozzles arranged in the main scanning direction formed on the nozzle plate. The variable mechanism changes the relative position and orientation of the head with respect to the surface to be painted. The control unit controls the operation of the head and the variable mechanism, respectively. The control unit, Of the multiple vibration frequency components included in the vibrations generated in at least one of the head and the variable mechanism when the liquid dispensing device performs a painting operation, the maximum vibration frequency component with the largest vibration amplitude, Based on the predetermined relative movement speed of the head by the variable mechanism, a group of nozzles selected from the plurality of nozzles is used to form a correction pattern on the surface to be painted. Based on the correction pattern formed on the surface to be painted, information regarding the rotation of the head is obtained with the rotation axis along the normal of the nozzle plate as the center of rotation. Based on information regarding the rotation of the head, the rotation of the head, which is moved relative to the head by the variable mechanism, is corrected and controlled to discharge the liquid from the head. A program that causes the liquid dispensing device to perform the processing.

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