A transfer coating system, a coating control method thereof, and a coating apparatus

Abstract

The application relates to the coating technical field, in particular to a transfer coating system, a coating control method thereof and a coating equipment. The transfer coating system collects the edge thickness of a slurry coating layer on line, controls the rotation of an angle control mechanism to adjust the feeding angle according to the difference between the edge thickness of the slurry coating layer and a preset thickness range, accurately adjusts the shearing force at the outlet of a doctor blade by adjusting the feeding angle, adjusts the slurry viscosity by changing the shearing force, and further adjusts the coating thickness. The shearing force regulation mechanism effectively suppresses the problems of slurry accumulation, thinning and coating leakage at the coating edge, so as to improve the thickness uniformity of the coating edge. The shearing thinning characteristics of the non-Newtonian fluid make the slurry viscosity controllable in spatial distribution, improve the coating stability of the edge area, and through on-line closed-loop feedback real-time regulation of the edge thickness, the overall coating consistency is significantly improved, the rework and the defective rate are reduced, and the coating process is suitable for various slurry systems.

Description

Technical Field

[0001] This application relates to the field of coating technology, and in particular to a transfer coating system and its coating control method and coating equipment. Background Technology

[0002] In precision manufacturing fields such as lithium-ion batteries, sodium-ion batteries, and optical films, transfer coating is widely used. This process typically involves a comma-shaped doctor blade evenly distributing fluid from a feed trough onto the surface of a transfer roller, which then presses the coating material onto the substrate surface. To ensure the uniformity of the coating thickness, existing processes largely rely on the following methods for control:

[0003] Fixed doctor blade structure and coating gap control: Set the physical distance between the doctor blade and the transfer roller to control the slurry thickness; Die head discharge channel optimization: Control the flow distribution between the center and the edge through CFD simulation or actual debugging; Transfer roller or back roller coating hardness adjustment: Match different coating hardness or diameter differences at different positions to balance the contact pressure; Process tension and speed control: Affect the slurry distribution by adjusting parameters such as coating speed and unwinding tension.

[0004] Although the above technologies have achieved controllability of coating thickness to a certain extent, the slurry is significantly affected by shear force, and excessive flow or fluid accumulation is prone to occur at the edges, resulting in severe edge accumulation or thinning, which reduces the coating quality of the product. Summary of the Invention

[0005] The purpose of this application is to provide a transfer coating system and its coating control method and coating equipment to solve the problem that existing coating methods are prone to accumulation or thinning at the coating edge.

[0006] In a first aspect, this application provides a transfer coating system, comprising:

[0007] A coating roller, wherein a slurry trough is provided on one side of the coating roller, and during the rotation of the coating roller, the slurry in the slurry trough is coated on the surface of the coating roller to form a coating area on the surface of the coating roller;

[0008] A back roller, which is used to transport the substrate during its rotation, so that the coating in the coating area is transferred to the surface of the substrate and a slurry coating is formed on the surface of the substrate;

[0009] The scraper is an elliptical structure with a curved surface and is set on one side of the coating roller by an angle control mechanism. The angle between the arc of the scraper blade and the horizontal tangent of the coating roller is the feeding angle. The angle control mechanism is used to adjust the feeding angle.

[0010] A thickness detection component is disposed on one side of the back roller and is used to collect the thickness of the slurry coating edge.

[0011] The control unit is electrically connected to the angle control mechanism and the thickness detection component, respectively, and is used to control the angle control mechanism to rotate to adjust the feeding angle based on the difference between the thickness of the slurry coating edge obtained by the thickness detection component and a preset thickness range.

[0012] In one possible implementation, the control unit includes:

[0013] The data processing module is used to compare the thickness of the slurry coating collected by the thickness detection component with a preset thickness range and generate a deviation value.

[0014] The control algorithm module is used to generate an angular adjustment command based on the deviation value;

[0015] An execution module is used to convert the angle adjustment command into a drive signal for the angle control mechanism, thereby realizing real-time adjustment of the feeding angle.

[0016] In one possible implementation, the control algorithm module includes:

[0017] The first control module is used to control the corner control mechanism to rotate to increase the feeding angle when the detected slurry coating at the edge of the substrate is greater than the upper limit of the preset thickness range.

[0018] The second control module is used to control the corner control mechanism to rotate to reduce the feeding angle when the slurry coating at the edge of the substrate is detected to be less than the lower limit of a preset thickness range.

[0019] In one possible implementation, the short axis of the scraper is set to be parallel to the horizontal tangent of the coating roller in the initial state. When the scraper rotates counterclockwise, the instantaneous radius of curvature of the scraper's cutting edge gradually changes from a first radius of curvature to a second radius of curvature, and the feed angle gradually decreases from a first angle value to a second angle value; wherein, the first radius of curvature is smaller than the second radius of curvature, and the second angle value is smaller than the first angle value.

[0020] In one possible implementation, the curvature gradient of the scraper satisfies the following relationship:

[0021]

[0022] Where θ is the rotation angle, a is the minor axis radius of the scraper, b is the major axis radius of the scraper, and R(θ) is the instantaneous radius of curvature of the cutting edge.

[0023] In one possible implementation, the adjustment range Δα of the feed angle and the deviation Δh of the preset thickness range value satisfy a linear relationship:

[0024] Δα=k Δh;

[0025] Where k is the adjustment coefficient (0.5° / μm≤k≤2° / μm), which is pre-calibrated based on the rheological properties of the slurry.

[0026] In one possible implementation, the first radius of curvature is 5 cm, the second radius of curvature is 10 cm, the first angle is 30°, and the second angle is 15°.

[0027] In one possible implementation, the first control module is configured to control the angle control mechanism to rotate to increase the feed angle to 22° when it detects that the slurry coating at the edge of the substrate is greater than a preset thickness value. 30°;

[0028] The second control module is used to control the corner control mechanism to rotate to reduce the feeding angle to 15° when it detects that the slurry coating at the edge of the substrate is greater than a preset thickness value. 22°.

[0029] In one possible implementation, increasing or decreasing the feed angle by 5° results in a corresponding decrease or increase of 20% in the slurry viscosity through the gap between the doctor blade and the coating roller.

[0030] Secondly, this application also provides a coating apparatus, including the transfer coating system described in the first aspect.

[0031] Secondly, this application also provides a coating control method based on the transfer coating system as described in the first aspect, the coating control method comprising:

[0032] S100 controls the rotation of the coating roller and back roller to start the coating process, obtains the initial feed angle formed between the doctor blade and the coating roller, and collects the edge thickness of the slurry coating online.

[0033] S200, determine whether the edge thickness of the slurry coating exceeds a preset thickness range;

[0034] S300, if the thickness exceeds the limit, the angle control mechanism is controlled to rotate to adjust the feeding angle based on the difference between the thickness of the slurry coating edge and the preset thickness range, until the thickness of the slurry coating edge stabilizes within the preset thickness range.

[0035] In one possible implementation, S300 specifically includes:

[0036] S310, when the slurry coating at the edge of the substrate is detected to be greater than the upper limit of the preset thickness range, the corner control mechanism is controlled to rotate to increase the feeding angle;

[0037] S320, when it is detected that the slurry coating at the edge of the substrate is less than the lower limit of the preset thickness range, the corner control mechanism is controlled to rotate to reduce the feeding angle.

[0038] This application has at least the following technical effects:

[0039] The transfer coating system provided in this application acquires the thickness of the slurry coating edge online and controls the rotation of the angle control mechanism to adjust the feed angle based on the difference between the slurry coating edge thickness and a preset thickness range. This allows for precise adjustment of the shear force at the doctor blade exit by adjusting the feed angle, and by changing the shear force, the slurry viscosity is adjusted, thereby adjusting the coating thickness. This application effectively suppresses problems such as slurry accumulation, thinning, and missed coating at the coating edge through a shear force control mechanism, thereby improving the uniformity of coating thickness at the edge. Utilizing the shear-thinning characteristics of non-Newtonian fluids, the spatial distribution of slurry viscosity is controllable, improving the coating stability in the edge area. Furthermore, the online closed-loop feedback allows for real-time control of the edge thickness, significantly improving overall coating consistency, reducing rework and defect rates. It is applicable to coating processes of various slurry systems and has a wide range of applications. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the overall structure of a transfer coating system provided in an embodiment of this application;

[0042] Figure 2 A schematic diagram of the module connection of a control system for a transfer coating system provided in an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the internal module connections of the control unit provided in an embodiment of this application;

[0044] Figure 4 This is a schematic diagram of the internal module connections of the control algorithm module provided in the embodiments of this application;

[0045] Figure 5 A schematic flowchart of a coating control method provided in an embodiment of this application;

[0046] Figure 6 This is a flowchart illustrating step S300 in a coating control method provided in an embodiment of this application.

[0047] Icons: 1-Tangent line of coating roller in the horizontal direction; 2-Feed angle; 3-Scraper; 4-Material trough; 5-Slurry accumulation area; 6-Angle control mechanism; 7-Coating roller; 8-Back roller; 9-Thickness detection component; 10-Control unit; 11-Data processing module; 12-Control algorithm module; 13-Execution module; 14-First control module; 15-Second control module. Detailed Implementation

[0048] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0050] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in the specification of this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0051] Combination Figure 1 and Figure 2 As shown, this application provides a transfer coating system, including: a coating roller 7, a back roller 8, a doctor blade 3, a thickness detection component 9, and a control unit 10.

[0052] Specifically, a slurry trough 4 is provided on one side of the coating roller 7. During the rotation of the coating roller 7, the slurry in the slurry trough 4 is coated onto the surface of the coating roller 7 to form a coating area on the surface of the coating roller 7. During the rotation of the back roller 8, it is used to transport the substrate. During the transport process, the coating in the coating area is transferred to the surface of the substrate and forms a slurry coating on the surface of the substrate.

[0053] In this embodiment, the scraper 3 adopts an elliptical structure with a curved surface. The scraper 3 is set on one side of the coating roller 7 through an angle control mechanism. The angle between the blade arc of the scraper 3 and the tangent 1 of the coating roller along the horizontal direction is set as the feeding angle 2. The scraper 3 is rotated by controlling the rotating shaft of the angle control mechanism 6, thereby adjusting the feeding angle 2 to correspond to different slurry viscosities.

[0054] It is understandable that transfer coating is usually greatly affected by viscosity changes. If the slurry viscosity is too high, the coating edge will be thick; if the slurry viscosity is too low, the slurry will accumulate and overflow, and the edge will be thin. Since transfer coating is generally an open trough 4, the slurry is in direct contact with the environment, which will generally cause the slurry viscosity to gradually deviate from the viscosity required for normal coating. In this case, this embodiment can change the viscosity of the slurry passing through the gap by increasing or decreasing the feed angle 2.

[0055] To facilitate adjustment of the slurry coating edge thickness, this embodiment uses a thickness detection component 9 on one side of the back roller 8 to collect (or detect) the slurry coating edge thickness. It should be noted that the thickness detection component 9 is positioned after the back roller 8 discharges material. A corresponding drying device is generally provided between the thickness detection component 9 and the back roller 8 to improve coating stability and ensure more accurate coating thickness detection. Optionally, the thickness detection component 9 can use a beta-ray, laser, or infrared thickness gauge to detect the slurry thickness.

[0056] The control unit 10 is electrically connected to the angle control mechanism 6 and the thickness detection component 9, respectively. Based on the difference between the edge thickness of the slurry coating obtained by the thickness detection component 9 and a preset thickness range, the control unit 10 controls the angle control mechanism 6 to rotate, thereby adjusting the feed angle 2. This adjustment of the feed angle 2 regulates the shear force at the exit of the scraper 3, and changes the slurry viscosity through the shear force, ultimately adjusting the coating thickness by reducing the viscosity. The preset thickness range can be considered the normal thickness range of the slurry coating; thicknesses within this range do not require adjustment of the feed angle 2.

[0057] This embodiment uses an online real-time edge thickness detection component to detect the coating thickness and feeds the detection data back to the control unit 10. The control unit 10 adjusts the angle control mechanism 6, thereby adjusting the angle between the blade arc of the scraper 3 and the tangent of the coating roller 7, thus changing the shear force distribution of the slurry at the exit of the scraper 3. Specifically, according to the pressure formula P = F / S, where P is the pressure, F is the pressure applied by the scraper 3 (usually kept stable within a certain range), and S is the fluid force-bearing area, when the feed angle 2 changes, causing the force-bearing area S to decrease, the pressure P per unit area increases, resulting in an increase in the shear force of the slurry in that area. Due to the shear thinning effect, the slurry viscosity decreases, and the fluidity increases, making edge overflow more likely. Figure 1 The amount of slurry accumulated in slurry accumulation area 5, as shown in the diagram, is related to the viscosity of the slurry. The lower the viscosity, the less slurry is accumulated in slurry accumulation area 5, and the higher the viscosity, the more slurry is accumulated in slurry accumulation area 5.

[0058] The transfer coating system provided in this application collects the thickness of the slurry coating edge online and controls the rotation of the angle control mechanism 6 to adjust the feed angle 2 based on the difference between the slurry coating edge thickness and the preset thickness range. This allows for precise adjustment of the shear force at the exit of the doctor blade 3 by adjusting the feed angle 2, and by changing the shear force, the viscosity of the slurry is adjusted, thereby adjusting the coating thickness. This application effectively suppresses problems such as coating edge accumulation, thinning, and missed coating through the shear force control mechanism, thereby improving the uniformity of coating edge thickness. By utilizing the shear thinning characteristics of non-Newtonian fluids, the spatial distribution of slurry viscosity is controllable, improving the coating stability in the edge area. Through online closed-loop feedback, the edge thickness is adjusted in real time, significantly improving the overall coating consistency, reducing rework and defect rates, and is applicable to coating processes of various slurry systems, with a wide range of applications.

[0059] In some embodiments, such as Figure 3 As shown, the control unit 10 includes: a data processing module 11, a control algorithm module 12, and an execution module 13.

[0060] Specifically, the data processing module 11 compares the slurry coating thickness collected by the thickness detection component 9 with a preset thickness range to generate a deviation value Δh. The control algorithm module 12 generates an angle adjustment command based on the deviation value Δh using a PID control algorithm. The execution module 13 converts the angle adjustment command into a drive signal for the angle control mechanism, thereby realizing real-time adjustment of the feeding angle 2.

[0061] Optionally, the adjustment range Δα of the feed angle 2 and the deviation Δh of the preset thickness range value satisfy a linear relationship: Δα=k Δh;

[0062] Where k is the adjustment coefficient (0.5° / μm≤k≤2° / μm), which is pre-calibrated based on the rheological properties of the slurry.

[0063] Optionally, such as Figure 4 As shown, the control algorithm module 12 includes: a first control module 14 and a second control module 15; the first control module 14 is used to control the corner control mechanism 6 to rotate to increase the feeding angle 2 when the slurry coating at the edge of the substrate is detected to be greater than the upper limit of the preset thickness range.

[0064] The second control module 15 is used to control the corner control mechanism 6 to rotate to reduce the feeding angle 2 when it is detected that the slurry coating at the edge of the substrate is less than the lower limit of the preset thickness range.

[0065] It should be noted that this embodiment is based on the shear-thinning characteristics of non-Newtonian fluids. By adjusting the feed angle 2, the shear force distribution of the slurry at the exit of the scraper 3 is changed. That is, this application achieves the adjustment of the coating layer edge thickness by changing the shear force to change the slurry viscosity, and thus changing the coating thickness through the fluid dynamics inherent control mechanism.

[0066] To describe the adjustment process of the feed angle 2 in detail, in the initial state, the short axis of the scraper 3 is parallel to the horizontal tangent 1 of the coating roller. When the scraper 3 rotates counterclockwise, the instantaneous radius of curvature of the scraper 3's cutting edge gradually changes from the first radius of curvature to the second radius of curvature, and the feed angle 2 gradually decreases from the first angle value to the second angle value. Wherein, the first radius of curvature is smaller than the second radius of curvature, and the second angle value is smaller than the first angle value. That is, the smaller the radius of curvature, the greater the degree of bending, and the larger the corresponding angle value.

[0067] Optionally, the curvature gradient of the scraper 3 satisfies the following relationship:

[0068]

[0069] Where θ is the rotation angle, a is the minor axis radius of scraper 3 (ellipse), b is the major axis radius of scraper 3 (ellipse), and R(θ) is the instantaneous radius of curvature of the cutting edge.

[0070] Optionally, the first radius of curvature is 5cm, the second radius of curvature is 10cm, the first angle is 30°, and the second angle is 15°. That is, when R(θ) is the instantaneous radius of curvature of the cutting edge is 5cm, the corresponding feed angle 2 is 30°, and when R(θ) is the instantaneous radius of curvature of the cutting edge is 10cm, the corresponding feed angle 2 is 15°. During the rotation of the scraper 3, the radius of curvature of its blade arc surface fluctuates in the range of 5cm to 10cm, and the corresponding feed angle 2 fluctuates in the range of 30° to 15°. By determining the correspondence of the above parameters, the corresponding adjustment can be achieved through the PID control algorithm, thereby enabling more precise adjustment of the thickness of the slurry coating edge.

[0071] Optionally, the first control module 14 is used to control the angle control mechanism 6 to rotate to increase the feeding angle 2 to 22° when it detects that the slurry coating at the edge of the substrate is greater than a preset thickness value. 30° reduces the shear force of the slurry, increases its viscosity, and reduces its fluidity to prevent overflow.

[0072] Optionally, the second control module 15 is used to control the angle control mechanism 6 to rotate to reduce the feeding angle by 2 to 15° when the slurry coating at the edge of the substrate is detected to be greater than a preset thickness value. 22° increases the pressure per unit area P (P=F / S, where S is the area of ​​the fluid subjected to force), enhances the shear force of the slurry, reduces the viscosity, and improves fluidity to suppress accumulation.

[0073] Optionally, for every 5° increase in the feed angle 2, the viscosity of the slurry passing through the gap between the doctor blade 3 and the coating roller 7 will decrease by 20%; or, for every 5° decrease in the feed angle 2, the viscosity of the slurry passing through the gap between the doctor blade 3 and the coating roller 7 will increase by 20%. This allows for the coating of high-viscosity and low-viscosity slurries. For example, for high-viscosity coating, the elliptical doctor blade 3 can be rotated counterclockwise to reduce the included angle, thereby reducing the viscosity and improving the edge thickness.

[0074] Secondly, this application also provides a coating apparatus, including the transfer coating system described in the foregoing embodiments. Furthermore, the coating apparatus also includes other components such as a support, a transmission mechanism, and a paint supply assembly. The specific installation methods of these structures can be found in existing coating apparatuses, and will not be described in detail in this embodiment.

[0075] The coating equipment provided in this application includes the transfer coating system of the aforementioned embodiment. This transfer coating system collects the thickness of the slurry coating edge online and controls the rotation of the angle control mechanism 6 to adjust the feed angle 2 based on the difference between the slurry coating edge thickness and the preset thickness range. By adjusting the feed angle 2, the shear force at the exit of the doctor blade 3 is precisely adjusted, and the slurry viscosity is adjusted by changing the shear force, thereby adjusting the coating thickness. This application effectively suppresses problems such as coating edge accumulation, thinning, and missed coating through the shear force control mechanism, thereby improving the thickness uniformity of the coating edge. By utilizing the shear thinning characteristics of non-Newtonian fluids, the slurry viscosity can be controlled in spatial distribution, improving the coating stability of the edge area. Through online closed-loop feedback to control the edge thickness in real time, the overall coating consistency is significantly improved, rework and defect rate are reduced, and it is applicable to coating processes of various slurry systems, with a wide range of applications.

[0076] The third aspect, such as Figure 5 As shown, this application also provides a coating control method based on the transfer coating system described in any of the foregoing embodiments. The coating control method includes:

[0077] S100 controls the rotation of coating roller 7 and back roller 8 to start the coating process, obtains the initial feed angle formed between doctor blade 3 and coating roller 7, and collects the edge thickness of slurry coating online.

[0078] Specifically, the initial feed angle can be obtained through the control unit 10 when the coating process is started, which makes it easy to adjust the feed angle 2 in a timely manner based on the collected thickness data, thereby improving the control efficiency.

[0079] S200, determine whether the edge thickness of the slurry coating exceeds the preset thickness range.

[0080] Specifically, the data processing module 11 inside the control unit 10 compares the thickness of the slurry coating edge with the preset thickness range and generates a specific deviation value.

[0081] S300, if the thickness exceeds the limit, the angle control mechanism 6 is controlled to rotate to adjust the feeding angle 2 according to the difference between the thickness of the slurry coating edge and the preset thickness range, until the thickness of the slurry coating edge is stable within the preset thickness range.

[0082] Specifically, when the thickness of the slurry coating edge exceeds the preset thickness range, it is considered to be out of tolerance. When the thickness exceeds the limit, the feed angle 2 needs to be adjusted according to the specific deviation value until the detected thickness meets the preset thickness range requirement.

[0083] Optionally, such as Figure 6 As shown, S300 specifically includes:

[0084] S310, when the slurry coating at the edge of the substrate is detected to be greater than the upper limit of the preset thickness range, the corner control mechanism 6 is controlled to rotate to increase the feeding angle 2.

[0085] S320, when the slurry coating at the edge of the substrate is detected to be less than the lower limit of the preset thickness range, the corner control mechanism 6 is rotated to reduce the feed angle 2.

[0086] It should be noted that when the control unit adjusts the feeding angle by rotating the angular control mechanism, the specific adjustment can be made according to the linear relationship between the adjustment range Δα of the feeding angle and the deviation value Δh of the preset thickness range value in the aforementioned embodiment. This will not be elaborated further here. Furthermore, steps S310 and S320 only represent two different control methods and do not indicate the order of the steps.

[0087] The coating control method provided in this application collects the thickness of the slurry coating edge online and controls the rotation of the angle control mechanism to adjust the feeding angle based on the difference between the slurry coating edge thickness and a preset thickness range. This allows for precise adjustment of the shear force at the doctor blade exit by adjusting the feeding angle, and by changing the shear force, the slurry viscosity is adjusted, thereby adjusting the coating thickness. Through the shear force control mechanism, problems such as coating edge accumulation, thinning, and missed coating are effectively suppressed, thereby improving the uniformity of coating edge thickness. By utilizing the shear thinning characteristics of non-Newtonian fluids, the spatial distribution of slurry viscosity is controllable, improving the coating stability in the edge area. Furthermore, by controlling the edge thickness in real time through online closed-loop feedback, the overall coating consistency is significantly improved, and rework and defect rates are reduced.

[0088] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0089] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0090] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. In the description of this specification, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A transfer coating system, characterized in that, include: A coating roller, wherein a slurry trough is provided on one side of the coating roller, and during the rotation of the coating roller, the slurry in the slurry trough is coated on the surface of the coating roller to form a coating area on the surface of the coating roller; A back roller, which is used to transport the substrate during its rotation, so that the coating in the coating area is transferred to the surface of the substrate and a slurry coating is formed on the surface of the substrate; The scraper is an elliptical structure with a curved surface and is set on one side of the coating roller by an angle control mechanism. The angle between the arc of the scraper blade and the horizontal tangent of the coating roller is the feeding angle. The angle control mechanism is used to adjust the feeding angle. A thickness detection component is disposed on one side of the back roller and is used to collect the thickness of the slurry coating edge. A control unit, electrically connected to both the angle control mechanism and the thickness detection component, is used to control the angle control mechanism to rotate and adjust the feed angle based on the difference between the slurry coating edge thickness obtained by the thickness detection component and a preset thickness range. This adjustment of the feed angle regulates the shear force at the scraper exit, and the shear force changes the slurry viscosity, thereby adjusting the coating thickness. The preset thickness range represents the normal thickness range of the slurry coating; if the thickness falls within this range, no adjustment of the feed angle is required. The control unit includes: The data processing module is used to compare the thickness of the slurry coating collected by the thickness detection component with a preset thickness range and generate a deviation value. The control algorithm module is used to generate angular adjustment commands based on the deviation value; An execution module is used to convert the angle adjustment command into a drive signal for the angle control mechanism, thereby realizing real-time adjustment of the feeding angle; The control algorithm module includes: The first control module is used to control the corner control mechanism to rotate to increase the feeding angle when the slurry coating at the edge of the substrate is detected to be greater than the upper limit of the preset thickness range, until the thickness of the slurry coating edge is stable within the preset thickness range. The second control module is used to control the corner control mechanism to rotate to reduce the feeding angle when the slurry coating at the edge of the substrate is detected to be less than the lower limit of the preset thickness range, until the thickness of the slurry coating edge is stable within the preset thickness range. In the initial state, the short axis of the scraper is parallel to the tangent of the coating roller in the horizontal direction. When the scraper rotates counterclockwise, the instantaneous radius of curvature of the scraper's cutting edge gradually changes from a first radius of curvature to a second radius of curvature, and the feed angle gradually decreases from a first angle value to a second angle value; wherein, the first radius of curvature is smaller than the second radius of curvature, and the second angle value is smaller than the first angle value; The first radius of curvature is 5cm and the first angle is 30°; the second radius of curvature is 10cm and the second angle is 15°. That is, during the rotation of the scraper, the instantaneous radius of curvature of its cutting edge fluctuates in the range of 5cm to 10cm, and the corresponding feeding angle fluctuates in the range of 30° to 15°.

2. The transfer coating system according to claim 1, characterized in that, The curvature gradient of the scraper satisfies the following relationship: Where θ is the rotation angle, a is the minor axis radius of the scraper, b is the major axis radius of the scraper, and R(θ) is the instantaneous radius of curvature of the cutting edge.

3. The transfer coating system according to claim 2, characterized in that, The adjustment range Δα of the feed angle and the deviation Δh of the preset thickness range value satisfy a linear relationship: Δα=k Δh; Where k is the adjustment coefficient (0.5° / μm≤k≤2° / μm), which is pre-calibrated based on the rheological properties of the slurry.

4. The transfer coating system according to claim 3, characterized in that, The first control module is used to control the corner control mechanism to rotate to increase the feeding angle to 22° when it detects that the slurry coating at the edge of the substrate is greater than a preset thickness value. 30°; The second control module is used to control the corner control mechanism to rotate to reduce the feeding angle to 15° when it detects that the slurry coating at the edge of the substrate is greater than a preset thickness value. 22°.

5. The transfer coating system according to claim 1, characterized in that, Increasing or decreasing the feed angle by 5° will correspondingly decrease or increase the viscosity of the slurry through the gap between the scraper and the coating roller by 20%.

6. A coating apparatus, characterized in that, Includes the transfer coating system as described in any one of claims 1 to 5.

7. A coating control method, characterized in that, Based on the transfer coating system as described in any one of claims 1 to 5, the coating control method includes: S100 controls the rotation of the coating roller and back roller to start the coating process, obtains the initial feed angle formed between the doctor blade and the coating roller, and collects the edge thickness of the slurry coating online. S200, determine whether the edge thickness of the slurry coating exceeds a preset thickness range; S300, if the thickness exceeds the limit, the angle control mechanism is controlled to rotate to adjust the feeding angle according to the difference between the thickness of the slurry coating edge and the preset thickness range, until the thickness of the slurry coating edge is stable within the preset thickness range; Specifically, S300 includes: S310, when the slurry coating at the edge of the substrate is detected to be greater than the upper limit of the preset thickness range, the corner control mechanism is controlled to rotate to increase the feeding angle; S320, when it is detected that the slurry coating at the edge of the substrate is less than the lower limit of the preset thickness range, the corner control mechanism is controlled to rotate to reduce the feeding angle.

Images