Inkjet head cleaning device and inkjet head cleaning method

Abstract

The present application relates to an inkjet head cleaning device and an inkjet head cleaning method. The inkjet head cleaning device includes: a first bath receiving a cleaning liquid from a supply tank, the first bath including a first bath bottom surface and a plurality of side walls connected to the first bath bottom surface, and the first bath having an open top; a second bath in contact with a first side wall among the plurality of side walls of the first bath, the second bath including a second bath bottom surface; a water level detection sensor configured to detect a water level in the second bath; and a controller configured to control an amount of the cleaning liquid supplied to the first bath according to the detected water level in the second bath; wherein a machined groove is provided on the first side wall of the first bath, and the cleaning liquid in the first bath overflows through the machined groove and is transported along the first side wall to the second bath.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0177074, filed on December 3, 2024, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure relates to an inkjet head cleaning apparatus and an inkjet head cleaning method for cleaning inkjet heads. Background Technology

[0004] Typically, substrate processing systems are used to perform predetermined processes (such as treating a substrate with a chemical liquid (also known as droplets or ink)) in order to manufacture semiconductors, displays, etc. For example, a substrate processing system can perform a printing process on a transparent substrate to manufacture display devices such as liquid crystal displays (LCDs), and for this purpose, an inkjet head can be provided. The inkjet head can eject ink onto the substrate to print the substrate.

[0005] However, when chemical liquids are applied to the inkjet head, these liquids may remain on the nozzle surface, causing defects. Therefore, the nozzle surface of the inkjet head needs to be cleaned periodically.

[0006] Therefore, maintenance has traditionally been performed repeatedly by simply cleaning the chemical liquid until the landing point of the chemical liquid discharged from the nozzle section of the inkjet head is maintained, or by draining the residual chemical liquid through a previous landing point operation before the main process, and replacing the inkjet head when the above measures fail to improve the situation. However, this leads to delays in inkjet processing equipment and results in high consumption costs for expensive inkjet heads.

[0007] Another method for cleaning inkjet heads is to immerse the nozzle surface of the inkjet head in a cleaning solution. The problem with this method is that it requires an extremely large amount of cleaning solution, as the solution must be continuously supplied during the cleaning process. Summary of the Invention

[0008] The purpose of this disclosure is to provide an apparatus and method for cleaning inkjet heads while reducing the amount of cleaning fluid used.

[0009] Another object of this disclosure is to provide an inkjet head cleaning apparatus and method, wherein cleaning fluid can overflow from a first bath having machined grooves into another bath, and a water level detection sensor disposed in the other bath can be used to control the supply of cleaning fluid to the first bath.

[0010] The purposes of this disclosure are not limited to those mentioned above, and other purposes not expressly stated will be clearly understood by those skilled in the art based on the following description.

[0011] According to one aspect of this disclosure, an inkjet head cleaning device includes: a first bath receiving cleaning fluid from a supply tank, the first bath including a first bath bottom surface and a plurality of sidewalls connected to the first bath bottom surface, and the first bath having an open top; a second bath configured to contact a first sidewall among the plurality of sidewalls of the first bath, the second bath including a second bath bottom surface; a water level detection sensor configured to detect a water level in the second bath; and a controller configured to control the amount of cleaning fluid supplied to the first bath based on the detected water level in the second bath; wherein a machined groove is provided on the first sidewall of the first bath, and the cleaning fluid in the first bath overflows through the machined groove and is conveyed along the first sidewall to the second bath.

[0012] According to one aspect of this disclosure, an inkjet head cleaning device includes: a supply tank; a first bath for receiving cleaning fluid from the supply tank, the first bath including a first bath bottom surface and a plurality of sidewalls connected to the first bath bottom surface, and the first bath having an open top; a supply line connecting the first bath and the supply tank; a first control valve disposed in the supply line and configured to control the supply of the cleaning fluid from the supply tank to the first bath; a second bath disposed in contact with a first sidewall of the plurality of sidewalls of the first bath, the second bath including a second bath bottom surface; a water level detection sensor configured to detect a water level in the second bath; a recovery tank configured to discharge the cleaning fluid from the second bath; and a recovery line connected to the second bath. The first bath includes: a recycling tank; a second control valve disposed in the recycling line and configured to control the cleaning fluid discharged from the second bath to the recycling tank; and a controller configured to control the amount of cleaning fluid supplied to the first bath based on a detected water level in the second bath; wherein a machined groove is disposed on the first sidewall of the first bath, through which the cleaning fluid in the first bath overflows and is transported along the first sidewall to the second bath; and the water level detection sensor includes: a first water level detection sensor positioned on the outside of one sidewall of the second bath; and a second water level detection sensor positioned on the outside of the one sidewall of the second bath and spaced apart from the first water level detection sensor in a first direction.

[0013] According to one aspect of this disclosure, an inkjet head cleaning method includes: supplying cleaning fluid to a first bath; overflowing the cleaning fluid in the first bath into a second bath through a machined groove; detecting the water level of the cleaning fluid using a water level detection sensor in the second bath; stopping the supply of the cleaning fluid to the first bath; and cleaning the nozzle surface by lowering the head.

[0014] It should be noted that the effects of this disclosure are not limited to those described above, and other effects of this disclosure will be apparent from the following description. Attached Figure Description

[0015] The above and other aspects and features of this disclosure will become more apparent from the detailed description of exemplary embodiments thereof with reference to the accompanying drawings, in which: Figure 1 This is a schematic configuration diagram showing an inkjet head cleaning apparatus according to an embodiment of the present disclosure; Figure 2 This is a cross-sectional view used to explain the machined groove provided in the first bath according to an embodiment of the present disclosure; Figure 3 yes Figure 2 An enlarged perspective view of region A is provided to explain the machined groove provided in the first bath according to an embodiment of the present disclosure. Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 This is a diagram used to explain the intermediate steps of the inkjet head cleaning method according to embodiments of the present disclosure; Figure 9 , Figure 10 , Figure 11 , Figure 12 and Figure 13 This is a diagram used to explain the intermediate steps of the inkjet head cleaning method according to embodiments of the present disclosure; Figure 14 This is a bottom view of the inkjet head, used to explain the nozzle surface having a chemical liquid discharge portion according to an embodiment of the present disclosure; Figure 15 This is a block diagram of an inkjet head cleaning apparatus according to an embodiment of the present disclosure; Figure 16 This is a block diagram of an inkjet head cleaning apparatus according to an embodiment of the present disclosure; Figure 17 This is a flowchart explaining the inkjet head cleaning method according to embodiments of the present disclosure; and Figure 18 This is a flowchart for explaining the inkjet head cleaning method according to embodiments of the present disclosure. Detailed Implementation

[0016] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The advantages and features of the present disclosure, as well as the methods for implementing them, will become apparent from the following detailed description of the embodiments and the accompanying drawings. However, the present disclosure is not limited to the embodiments set forth below, but may be implemented in various other forms. These embodiments are provided only to ensure a complete description of the present disclosure and to fully communicate the scope of the disclosure to those skilled in the art. The present disclosure is defined only by the scope of the claims. Throughout the specification, the same reference numerals denote the same elements.

[0017] Although terms such as "first," "second," etc., are used to describe various elements, components, and / or parts, it should be understood that these elements, components, and / or parts are not limited by these terms. These terms are used only to distinguish one element, component, or part from another element, component, or part. Therefore, within the scope of this disclosure, the first element, first component, or first region mentioned below may also be a second element, second component, or second region.

[0018] The terminology used herein is for descriptive purposes only and is not intended to limit this disclosure. In this specification, the singular form includes the plural form as well as the singular form, unless the context clearly indicates otherwise. The terms “comprises” and / or “comprising” as used herein specify the presence of the said components, steps, operations, and / or elements, but do not exclude the presence or addition of one or more other components, steps, operations, and / or elements.

[0019] In this specification, the term "chemical liquid" may be used interchangeably with "ink," "substrate liquid," or "processing liquid," which have the same meaning.

[0020] Figure 1 This is a schematic configuration diagram showing an inkjet head cleaning apparatus according to an embodiment of the present disclosure. Figure 2 This is a cross-sectional view used to explain the machined groove provided in the first bath according to an embodiment of the present disclosure.

[0021] Reference Figure 1 , Figure 2 and Figure 3 The inkjet head cleaning device 1000 may include a first bath 100, a first control valve 110, a machined groove 120, a second bath 200, a second control valve 210, a first water level detection sensor 220, a second water level detection sensor 230, a supply tank 300, a supply line 310, a recovery tank 400, a recovery line 410, and a controller 500.

[0022] The inkjet head cleaning device 1000 is an apparatus for cleaning a head 10, which can be used to perform printing processes on a substrate to manufacture display devices such as liquid crystal displays (LCDs). Typically, the head 10 can be cleaned by simply rinsing off any remaining chemical liquid in the chemical liquid discharge portion 12 of the head 10, or by using a filament cleaner to clean the chemical liquid discharge portion 12 of the nozzle surface 11. Conversely, the inkjet head cleaning device 1000 cleans the chemical liquid discharge portion 12 of the head 10 by immersing the nozzle surface 11 in a cleaning solution 20.

[0023] The first bath 100 may include a first bath bottom surface 100LS. The first bath 100 may include a plurality of sidewalls connected to the first bath bottom surface 100LS. Among the plurality of sidewalls, a first sidewall 100SW may be installed to contact the second bath 200. The first bath 100 is open at its top.

[0024] The head 10 can be cleaned in the first bath 100. Specifically, the head 10 may include a nozzle. The nozzle surface 11 of the nozzle may include a chemical liquid discharge portion 12. The chemical liquid discharge portion 12 of the nozzle surface 11 can be immersed in the cleaning liquid 20 in the first bath 100, thereby enabling cleaning. The supply tank 300 can supply the cleaning liquid 20 to the first bath 100. The cleaning liquid 20 can be supplied to the first bath 100 through the bottom surface 100LS of the first bath. The supply line 310 can connect the first bath 100 and the supply tank 300. A first control valve 110 can be arranged in the supply line 310 to control the supply of the cleaning liquid 20 from the supply tank 300 to the first bath 100.

[0025] Reference Figure 2 and Figure 3 The first bath 100 may have a machined groove 120 formed in its first sidewall 100SW. The machined groove 120 may be located on the uppermost surface of the first sidewall 100SW of the first bath 100. The machined groove 120 may include a V-shaped cut. The machined groove 120 may allow cleaning fluid 20 to overflow from the first bath 100 into the second bath 200. The overflowed cleaning fluid 20 may be conveyed along the first sidewall 100SW of the first bath 100 to the second bath 200. Figure 2 and Figure 3As shown, a single machined groove 120 can be provided, but this is merely exemplary. That is, there is no particular limitation on the number of machined grooves 120. Optionally, multiple machined grooves 120 can be provided on the uppermost surface of the first sidewall 100SW of the first bath 100. The machined grooves 120 can allow the cleaning fluid 20 in the first bath 100 to overflow in one direction. The shape of the machined groove 120 may include a V-shaped cut, but the shape of the machined groove 120 is not limited to this. For example, although not shown, the shape of the machined groove 120 may include a U-shaped cut.

[0026] The second bath 200 can be arranged to connect to the first bath 100. Specifically, the second bath 200 can be installed to contact the first sidewall 100SW of the first bath 100. The second bath 200 can contain cleaning fluid 20 overflowing through the machined groove 120 of the first bath 100.

[0027] The capacity of the second bath 200 can be smaller than that of the first bath 100. The bottom surface 100LS of the first bath and the bottom surface 200LS of the second bath can be located on the same plane. Being on the same plane can mean having the same height in the first direction D1. The height h100 of the first bath 100 can be greater than the height h200 of the second bath 200. The first direction D1 can be a height direction, and the second direction D2 and the third direction D3 can be perpendicular to the first direction D1.

[0028] The cleaning solution 20 in the second bath 200 can be discharged to the recovery tank 400 through the bottom surface 200LS of the second bath. The recovery line 410 can connect the second bath 200 and the recovery tank 400. A second control valve 210 can be arranged in the recovery line 410 to control the discharge of the cleaning solution 20 from the second bath 200 to the recovery tank 400.

[0029] The second bath 200 may include at least one water level detection sensor for detecting the water level of the cleaning solution 20. (See reference...) Figure 1 The second bath tub 200 may include a first water level detection sensor 220 and a second water level detection sensor 230. The first water level detection sensor 220 may be disposed on the outer side of one sidewall of the second bath tub 200. The second water level detection sensor 230 may be disposed on the inner or outer side of the sidewall of the second bath tub 200, spaced apart from the first water level detection sensor 220 in a first direction D1. When the first water level detection sensor 220 and the second water level detection sensor 230 are positioned on the outer side of the sidewall of the second bath tub 200, they can detect the water level of the cleaning solution 20 in a non-contact manner. The first water level detection sensor 220 and the second water level detection sensor 230 can input the detected water level to the controller 500.

[0030] When the water level of the cleaning solution 20 in the second bath 200 rises above the first water level h1, the first water level detection sensor 220 can input detection information to the controller 500. When the water level of the cleaning solution 20 in the second bath 200 rises above the second water level h2, the second water level detection sensor 230 can input detection information to the controller 500. The controller 500, having received the detection information, can control the opening and closing of the first control valve 110. When the water level of the cleaning solution 20 in the second bath 200 exceeds the first water level h1, the controller 500 can control the first control valve 110 to close. When the first control valve 110 is closed, the supply of cleaning solution 20 from the supply tank 300 to the first bath 100 can be stopped. When the water level of the cleaning solution 20 in the second bath 200 exceeds the second water level h2, the second water level detection sensor 230 can input detection information to the controller 500. The controller 500, having received the detection information, can control the opening and closing of the first control valve 110. When the first control valve 110 is closed, the supply of cleaning fluid 20 from the supply tank 300 to the first bath 100 can be stopped. That is, the detection information input to the controller 500 from the first water level detection sensor 220 and the second water level detection sensor 230 can be used to control the opening and closing of the first control valve 110.

[0031] The first control valve 110 and the second control valve 210 are in Figure 1 The text shows that all of them are in the open state.

[0032] The recovery tank 400 can recover the cleaning fluid 20 discharged from the second bath 200. Although not shown, the cleaning fluid 20 in the recovery tank 400 can be reused. Although not shown, the cleaning fluid 20 in the recovery tank 400 can be transported to a waste liquid tank. The destination of the cleaning fluid 20 in the recovery tank 400 can be determined by considering factors such as contamination of the cleaning fluid 20.

[0033] The controller 500 can be electrically connected to the first water level detection sensor 220 and the second water level detection sensor 230. The controller 500 can receive detection information from the first and second water level detection sensors 220 and 230 based on the water level in the second bath 200. The controller 500 can control the opening and closing of the first control valve 110 based on the received detection information. That is, the controller 500 can control the amount of cleaning fluid 20 supplied to the first bath 100 based on the detected water level in the second bath 200.

[0034] Although not shown, the controller 500 can be electrically connected to the first control valve 110 and the second control valve 210. When the water level in the second bath 200 exceeds the first water level h1, the controller 500 can control the first control valve 110 to close. When the water level in the second bath 200 exceeds the second water level h2, the controller 500 can control the first control valve 110 to close. After cleaning the nozzle surface 11 is completed, the controller 500 can control the cleaning fluid 20 in the second bath 200 to drain into the recovery tank 400. To drain the fluid, the controller 500 can control the second control valve 210 to open.

[0035] Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 This is a diagram used to explain the intermediate steps of the inkjet head cleaning method according to embodiments of the present disclosure.

[0036] Specifically, Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 This diagram illustrates the process by which the controller 500 controls the supply of cleaning fluid 20 to the first bath 100 based on detection information from the first water level detection sensor 220.

[0037] Reference Figure 4 Cleaning solution 20 can be supplied from supply tank 300 to first bath 100. Cleaning solution 20 can be supplied to first bath 100 through bottom surface 100LS. First bath 100 can be filled with cleaning solution 20, and due to surface tension, the uppermost surface 20US of cleaning solution 20 can protrude above first bath 100. (Refer to...) Figure 4 The first control valve 110 is opened, and the second control valve 210 is closed.

[0038] Reference Figure 5 The cleaning fluid 20 overflowing from the first bath 100 can pass through the machined groove 120 provided on the uppermost surface of the first sidewall 100SW of the first bath 100 (in Figure 2 The cleaning solution 20 overflowing from the first bath 100 can be conveyed to the second bath 200 along the first sidewall 100SW of the first bath 100.

[0039] The first water level sensor 220 can detect whether the water level of the cleaning fluid 20 in the second bath 200 has reached the first water level h1. When the water level of the cleaning fluid 20 overflowing from the first bath 100 into the second bath 200 reaches the first water level h1, the first water level sensor 220 can input detection information to the controller 500. The controller 500 can control the first control valve 110 to close based on the detection information from the first water level sensor 220. When the first control valve 110 is closed, the supply of cleaning fluid 20 from the supply tank 300 to the first bath 100 can be stopped. (Refer to...) Figure 5 and Figure 6 The first control valve 110 and the second control valve 210 are closed.

[0040] Reference Figure 6 When the supply of cleaning fluid 20 to the first bath 100 is stopped, the cleaning fluid 20 filled in the first bath 100 can be used to clean the nozzle surface 11 of the head 10. The head 10 can move downward in the direction opposite to the first direction D1. The nozzle surface 11 of the head 10 can be cleaned by the cleaning fluid 20 filled in the first bath 100. Specifically, when the uppermost surface 20US of the cleaning fluid 20 in the first bath 100 protrudes above the first bath 100 due to surface tension, the nozzle surface 11 can be immersed in the cleaning fluid 20 for cleaning. Cleaning the nozzle surface 11 may include cleaning the chemical liquid discharge portion 12 provided on the nozzle surface 11. Chemical liquid adhering to the chemical liquid discharge portion 12 can be removed by the cleaning fluid 20. The cleaning fluid 20 can be used to clean any blocked chemical liquid discharge portion 12.

[0041] Reference Figure 7 and Figure 8 After cleaning the nozzle surface 11, the head 10 can move upward in the first direction D1. After cleaning the nozzle surface 11, the cleaning fluid 20 in the second bath 200 can be discharged into the recovery tank 400. Specifically, the cleaning fluid 20 can be discharged into the recovery tank 400 through the bottom surface 200LS of the second bath. The controller 500 can command the second control valve 210 to open, so that the cleaning fluid 20 in the second bath 200 is discharged into the recovery tank 400. The second control valve 210, provided in the recovery line 410, can be used to control the amount of cleaning fluid 20 discharged from the second bath 200 to the recovery tank 400 by opening and closing operations. The cleaning fluid 20 in the second bath 200 can be completely discharged into the recovery tank 400. After the discharge into the recovery tank 400 is completed, the controller 500 can command the second control valve 210 to close.

[0042] After the cleaning solution 20 is discharged from the second bath 200, the controller 500 can resume supplying the cleaning solution 20 to the first bath 100. The controller 500 can control the resumption of the supply of cleaning solution 20 from the supply tank 300 to the first bath 100. The controller 500 can control the first control valve 110 to open, thereby resuming the supply of cleaning solution 20 to the first bath 100. When the first control valve 110 is open, cleaning solution 20 can be supplied until the first water level detection sensor 220 detects that the water level in the second bath 200 has reached the first water level h1. (Refer to...) Figure 7 and Figure 8 The first control valve 110 is opened, and the second control valve 210 is closed.

[0043] Figure 9 , Figure 10 , Figure 11 , Figure 12 and Figure 13 This is a diagram used to explain the intermediate steps of the inkjet head cleaning method according to embodiments of the present disclosure.

[0044] Figure 9 , Figure 10 , Figure 11 , Figure 12 and Figure 13 This is a diagram used to explain the process by which the controller 500 controls the supply of cleaning fluid 20 to the first bath 100 based on detection information from the second water level detection sensor 230.

[0045] Reference Figure 9 and Figure 10 The cleaning solution 20 can be supplied from the supply tank 300 to the first bath 100 through the bottom surface 100LS of the first bath. The first bath 100 can be filled with the cleaning solution 20, and due to surface tension, the uppermost surface 20US of the cleaning solution 20 can protrude above the first bath 100.

[0046] The first water level sensor 220 may malfunction or fail. In this case, even when the water level in the second bath 200 reaches the first water level h1, the first water level sensor 220 cannot detect the water level of the cleaning fluid 20. The first water level sensor 220 cannot input detection information to the controller 500. When the first water level sensor 220 malfunctions or fails, the cleaning fluid 20 can continue to be supplied to the first bath 100 even when the water level in the second bath 200 reaches the first water level h1. Therefore, the water level in the second bath 200 can become higher than the first water level h1. When the water level of the cleaning fluid 20 overflowing from the first bath 100 into the second bath 200 reaches the second water level h2, the second water level sensor 230 can input detection information to the controller 500. The controller 500 can control the first control valve 110 to close based on the detection information from the second water level sensor 230. When the first control valve 110 is closed, the supply of cleaning fluid 20 from the supply tank 300 to the first bath 100 can be stopped. Reference Figure 9 The first control valve 110 opens, and the second control valve 210 closes. (Refer to...) Figure 10 The first control valve 110 and the second control valve 210 are closed.

[0047] Reference Figure 11 When the supply of cleaning fluid 20 to the first bath 100 is stopped, the cleaning fluid 20 filled in the first bath 100 can be used to clean the nozzle surface 11 of the head 10. The head 10 can move downward in the direction opposite to the first direction D1. The nozzle surface 11 of the head 10 can be cleaned by the cleaning fluid 20 filled in the first bath 100. Specifically, when the uppermost surface 20US of the cleaning fluid in the first bath 100 protrudes above the first bath 100 due to surface tension, the nozzle surface 11 can be immersed in the cleaning fluid 20 for cleaning. Cleaning the nozzle surface 11 may include cleaning the chemical liquid discharge portion 12 provided on the nozzle surface 11. Chemical liquid adhering to the chemical liquid discharge portion 12 can be removed by the cleaning fluid 20. The cleaning fluid 20 can be used to clean the blocked chemical liquid discharge portion 12. See reference. Figure 11 The first control valve 110 and the second control valve 210 are closed.

[0048] Reference Figure 12 and Figure 13After cleaning the nozzle surface 11, the head 10 can move upward in the first direction D1. The cleaning fluid 20 in the second bath 200 can then be discharged into the recovery tank 400. Specifically, the cleaning fluid 20 can be discharged into the recovery tank 400 through the bottom surface 200LS of the second bath. The controller 500 can command the second control valve 210 to open, causing the cleaning fluid 20 in the second bath 200 to be discharged into the recovery tank 400. The second control valve 210, located in the recovery line 410, can be used to control the amount of cleaning fluid 20 discharged from the second bath 200 to the recovery tank 400 by opening and closing operations. The cleaning fluid 20 in the second bath 200 can be completely discharged into the recovery tank 400. After the discharge into the recovery tank 400 is completed, the controller 500 can command the second control valve 210 to close.

[0049] After the cleaning solution 20 is discharged from the second bath 200, the controller 500 can resume supplying the cleaning solution 20 to the first bath 100. The controller 500 can control the resumption of the supply of cleaning solution 20 from the supply tank 300 to the first bath 100. The controller 500 can control the first control valve 110 to open, thereby resuming the supply of cleaning solution 20 to the first bath 100. When the first control valve 110 is open, cleaning solution 20 can be supplied until the second water level detection sensor 230 detects that the water level in the second bath 200 has reached the second water level h2. (Refer to...) Figure 12 and Figure 13 The first control valve 110 is opened, and the second control valve 210 is closed.

[0050] Figure 14 This is a bottom view for explaining an inkjet head with a nozzle surface having a chemical liquid discharge portion according to an embodiment of the present disclosure.

[0051] Reference Figure 14 The head 10 may include a nozzle. The nozzle may include a nozzle surface 11. Multiple chemical liquid discharge portions 12 may be disposed on the nozzle surface 11. Figure 14 As shown, ten chemical liquid discharge sections 12 can be provided, but the number of chemical liquid discharge sections 12 is not limited to this. Chemical liquids used for various processes and substrate treatments can be discharged from the chemical liquid discharge sections 12. The chemical liquids may include ink. The chemical liquids may include substrate liquids. The chemical liquids may include processing liquids. When the chemical liquids are repeatedly discharged from the chemical liquid discharge sections 12, the chemical liquids may be dispersed on the nozzle surface 11. When the chemical liquids are repeatedly discharged from the chemical liquid discharge sections 12, there may be residual chemical liquids on the chemical liquid discharge sections 12. Here, the inkjet head cleaning device 1000 is a device that uses a cleaning solution to clean the nozzle surface 11 and the chemical liquid discharge sections 12 provided on the nozzle surface 11.

[0052] Figure 15 This is a block diagram of an inkjet head cleaning apparatus according to an embodiment of the present disclosure. Figure 16 This is a block diagram of an inkjet head cleaning apparatus according to an embodiment of the present disclosure.

[0053] The controller 500 can be electrically connected to the first water level detection sensor 220 and the second water level detection sensor 230.

[0054] The controller 500 can receive the detection results sensed by the first water level detection sensor 220. When the water level of the cleaning liquid 20 in the second bath 200 reaches the first water level h1, the first water level detection sensor 220 can input the detection results to the controller 500.

[0055] The controller 500 can receive the detection results sensed by the second water level detection sensor 230. When the water level of the cleaning liquid 20 in the second bath 200 reaches the second water level h2, the second water level detection sensor 230 can input the detection result to the controller 500.

[0056] The controller 500 can be electrically connected to the first control valve 110 and the second control valve 210.

[0057] The controller 500 can receive detection information from the first water level detection sensor 220 and the second water level detection sensor 230, and can control the opening and closing of the first control valve 110.

[0058] When the water level of the cleaning solution 20 in the second bath 200 reaches the first water level h1, the first water level detection sensor 220 can input the detection result to the controller 500. The controller 500 can receive the detection information from the first water level detection sensor 220 and can control the first control valve 110 to close.

[0059] When the water level of the cleaning solution 20 in the second bath 200 reaches the second water level h2, the second water level detection sensor 230 can input the detection result to the controller 500. The controller 500 can receive the detection information from the second water level detection sensor 230 and can control the first control valve 110 to close.

[0060] After the first 10 cleaning is completed, the controller 500 can control the second control valve 210 to open. When the second control valve 210 is opened, the cleaning solution 20 in the second bath 200 can be discharged into the recovery tank 400 along the recovery line 410.

[0061] After the first 10 cleaning is completed, the controller 500 can control the first control valve 110 to open. When the first control valve 110 is open, the first bath 100 can receive cleaning fluid 20 from the supply tank 300 along the supply line 310.

[0062] Figure 17 This is a flowchart for explaining the inkjet head cleaning method according to embodiments of the present disclosure.

[0063] Cleaning solution 20 can be supplied from supply tank 300 to first bath 100 (S110).

[0064] The cleaning fluid 20 in the first bath 100 can overflow into the second bath 200 through the machined groove 120 (S120). The cleaning fluid 20 overflowing from the first bath 100 can be transported to the second bath 200 along the first side wall 100SW of the first bath 100.

[0065] The water level of the cleaning solution 20 in the second bath 200 can be raised to the first water level h1 (S130). When the water level of the cleaning solution 20 in the second bath 200 rises to the first water level h1, the first water level detection sensor 220 can input detection information to the controller 500.

[0066] The controller 500 can close the first control valve 110 to stop the supply of cleaning fluid 20 to the first bath 100 (S140). The controller 500 can control the first control valve 110 to close based on detection information input from the first water level detection sensor 220.

[0067] The head 10 can move downwards, causing the nozzle surface 11 to immerse in the first bath 100 and perform cleaning (S150). The head 10 may include a nozzle. In this disclosure, the expression for the head 10 moving downwards can be used interchangeably with the expression for the nozzle moving downwards. During cleaning, due to surface tension, the uppermost surface 20US of the cleaning fluid 20 in the first bath 100 may protrude beyond the first bath 100 in the first direction D1. After cleaning is completed, the head 10 can move upwards in the first direction D1.

[0068] After cleaning is completed, the second control valve 210 can be opened to drain the cleaning solution 20 in the second bath 200 to the recovery tank 400 (S160). The controller 500 can control the opening and closing of the second control valve 210.

[0069] Figure 18 This is a flowchart for explaining the inkjet head cleaning method according to embodiments of the present disclosure.

[0070] Cleaning solution 20 can be supplied from supply tank 300 to first bath 100 (S210).

[0071] The cleaning fluid 20 in the first bath 100 can overflow into the second bath 200 through the machined groove 120 (S220). The cleaning fluid 20 overflowing from the first bath 100 can be transported to the second bath 200 along the first side wall 100SW of the first bath 100.

[0072] The water level of the cleaning solution 20 in the second bath 200 can be raised to the first water level h1 (S230).

[0073] When the first water level detection sensor 220 malfunctions, sensing cannot be performed even if the cleaning fluid 20 reaches the first water level h1 (S240). When the first water level detection sensor 220 malfunctions, it cannot input detection information to the controller 500.

[0074] The water level of the cleaning solution 20 in the second bath 200 can be raised to the second water level h2 (S250). When the water level of the cleaning solution 20 in the second bath 200 rises to the second water level h2, the second water level detection sensor 230 can input detection information to the controller 500.

[0075] The controller 500 can close the first control valve 110 to stop the supply of cleaning fluid 20 to the first bath 100 (S260). The controller 500 can control the first control valve 110 to close based on detection information input from the second water level detection sensor 230.

[0076] The head 10 can move downwards, causing the nozzle surface 11 to be immersed in the first bath 100 and performing cleaning (S270). The head 10 may include a nozzle. In this disclosure, the expression for the head 10 moving downwards can be used interchangeably with the expression for the nozzle moving downwards. During cleaning, due to surface tension, the uppermost surface 20US of the cleaning fluid 20 in the first bath 100 may protrude beyond the first bath 100 in the first direction D1. After cleaning is completed, the head 10 may move upwards in the first direction D1.

[0077] After cleaning is completed, the second control valve 210 can be opened to drain the cleaning solution 20 in the second bath 200 into the recovery tank 400 (S280). The controller 500 can control the opening and closing of the second control valve 210.

[0078] Although embodiments based on the technical concept of this disclosure have been described with reference to the accompanying drawings, this disclosure is not limited to these embodiments, but can be made in various different forms, and those skilled in the art will understand that this disclosure can be implemented in other specific forms without changing the technical concept or essential characteristics of this disclosure. Therefore, the above embodiments should be understood as illustrative in all respects and not restrictive.

Claims

1. An inkjet head cleaning device, comprising: A first bath receives cleaning fluid from a supply tank. The first bath includes a bottom surface and a plurality of sidewalls connected to the bottom surface, and the first bath has an open top. The second bath is in contact with a first sidewall among the plurality of sidewalls of the first bath, and the second bath includes a bottom surface of the second bath. A water level detection sensor is configured to detect the water level in the second bath. as well as The controller is configured to control the amount of cleaning liquid supplied to the first bath based on the detected water level in the second bath. in, The machined groove is provided on the first side wall of the first bath, and The cleaning fluid in the first bath overflows through the machined groove and is transported along the first sidewall to the second bath.

2. The inkjet head cleaning device according to claim 1, wherein, The machined groove includes a V-shaped cut on the uppermost surface of the first sidewall.

3. The inkjet head cleaning device according to claim 1, wherein, The cleaning solution is supplied to the first bath tub through the bottom surface of the first bath tub.

4. The inkjet head cleaning device according to claim 3 further includes: A supply line connects the first bath and the supply tank.

5. The inkjet head cleaning device according to claim 4, further comprising: A first control valve is disposed in the supply line and configured to control the cleaning fluid supplied from the supply tank to the first bath.

6. The inkjet head cleaning device according to claim 1, further comprising: A recovery tank is configured to allow the cleaning solution in the second bath to drain through the bottom surface of the second bath.

7. The inkjet head cleaning device according to claim 6, further comprising: A recovery pipeline connects the second bath and the recovery tank.

8. The inkjet head cleaning device according to claim 7, further comprising: A second control valve is disposed in the recovery pipeline and configured to control the discharge of the cleaning fluid from the second bath into the recovery tank.

9. The inkjet head cleaning device according to claim 1, wherein, The bottom surfaces of the first and second bathtubs are located on the same plane, and The height of the first bath tub is greater than the height of the second bath tub.

10. The inkjet head cleaning device according to claim 1, wherein, The water level detection sensor includes: The first water level detection sensor is positioned on the outer side of one side wall of the second bath; and The second water level sensor is positioned on the outside of one sidewall of the second bath and spaced apart from the first water level sensor in a first direction.

11. The inkjet head cleaning device according to claim 10, wherein, The first water level detection sensor detects whether the water level in the second bath has reached the first water level, and The second water level detection sensor detects whether the water level in the second bath has reached a second water level that is higher than the first water level.

12. The inkjet head cleaning device according to claim 1, wherein, The water level detection sensor detects that the water level in the second bath has reached the first water level. Then, based on the detection result from the water level detection sensor, the controller stops supplying the cleaning solution to the first bath. Then, the nozzle surface is cleaned using the cleaning solution filled in the first bath. Then, the cleaning solution in the second bath is drained.

13. The inkjet head cleaning device according to claim 12, wherein, After the cleaning fluid is drained from the second bath, the controller resumes supplying the cleaning fluid to the first bath, and the cleaning fluid is supplied to the first bath until the water level detection sensor detects that the water level in the second bath has reached the first water level.

14. The inkjet head cleaning device according to claim 1, wherein, With the first bath filled with the cleaning liquid and the uppermost surface of the cleaning liquid protruding beyond the first bath due to surface tension, the nozzle surface is immersed in the cleaning liquid and cleaned.

15. An inkjet head cleaning device, comprising: Supply tank; A first bath receives cleaning fluid from the supply tank. The first bath includes a bottom surface and a plurality of sidewalls connected to the bottom surface, and the first bath has an open top. A supply pipeline connects the first bath tub and the supply tank; A first control valve is disposed in the supply line and configured to control the cleaning fluid supplied from the supply tank to the first bath. The second bath is configured to contact a first sidewall among the plurality of sidewalls of the first bath, and the second bath includes a bottom surface of the second bath. A water level detection sensor is configured to detect the water level in the second bath. A recovery tank is configured to discharge the cleaning solution from the second bath. A recovery pipeline connects the second bath and the recovery tank; A second control valve is disposed in the recovery pipeline and configured to control the cleaning fluid discharged from the second bath into the recovery tank; as well as The controller is configured to control the amount of cleaning liquid supplied to the first bath based on the detected water level in the second bath. in, The machined groove is provided on the first side wall of the first bath. The cleaning solution in the first bath overflows through the machined groove and is conveyed along the first sidewall to the second bath. The water level detection sensor includes: a first water level detection sensor located on the outer side of one side wall of the second bath; and a second water level detection sensor located on the outer side of the one side wall of the second bath and spaced apart from the first water level detection sensor in a first direction.

16. The inkjet head cleaning device according to claim 15, wherein, The controller is configured to control the opening and closing of the first control valve based on detection information input from the water level detection sensor.

17. A method for cleaning an inkjet head, comprising: Supply the cleaning solution to the first bath; The cleaning solution in the first bath overflows into the second bath through a machined groove; The water level of the cleaning solution is detected by the water level detection sensor in the second bath. Stop supplying the cleaning solution to the first bath; as well as Clean the nozzle surface by lowering the head.

18. The inkjet head cleaning method according to claim 17, further comprising: After cleaning the nozzle surface, the cleaning solution in the second bath is drained into a recovery tank.

19. The inkjet head cleaning method according to claim 17, wherein, Cleaning the nozzle surface includes immersing the nozzle surface in the cleaning solution in the first bath.

20. The inkjet head cleaning method according to claim 17, further comprising: After cleaning the nozzle surface, raise the head.

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