Coating device

Abstract

The utility model provides a coating device, which comprises a die head main body provided with an upper die head, a lower die head and a discharge slit formed between the upper die head and the lower die head; the plurality of coating runners are independently arranged in the upper die head or the lower die head and are communicated with the discharging slit; the coating runner is obliquely arranged relative to the plane where the discharging slit is located; and the plurality of metering pumps are communicated with the plurality of coating runners in a one-to-one manner and can be used for metering and adjusting the material passing amount, so that the flow of each coating runner is consistent. Therefore, due to the inclined design of the coating runner, cleaning is facilitated, dead corners are fewer, slurry is not prone to deposition, and discharging uniformity is guaranteed. And moreover, closed-loop adjustment can be carried out on the material passing amount of each coating runner through the metering pump, the coating uniformity can be improved, and the coating quality is improved.

Description

Technical Field

[0001] This application relates to the technical field of coating equipment, and particularly to a coating device. Background Art

[0002] Currently, the extrusion coating technology in the market is the main technical means for coating lithium battery electrodes. However, since the design of the extrusion coating die head is closely related to the flow properties of the lithium battery slurry, its design technology is complex, time-consuming and laborious. Moreover, due to the different properties of the battery slurry in different batches, it often causes the slurry to be mismatched with the coating die head, exceeding the adjustment ability of the die head.

[0003] In the prior art, in order to make the slurry thickness consistent at the die head lip, an adjustment mechanism is provided at a position close to the lip of the extrusion coating die head. After the slurry enters the die head, it is ejected through the die head lip, and the outlet size at different discharge positions is adjusted by a plurality of adjustment mechanisms at the lip. However, the adjustment range of this adjustment method is limited, and the manufacturing precision requirements for parts are high. If the cooperation is not good, it will affect the coating quality. When the adjustment ranges of different adjustment mechanisms are different, they will affect each other, resulting in an increase or decrease in the discharge pressure in adjacent areas, or an increase or decrease in the discharge flow rate in adjacent areas, resulting in uneven coating thickness. Moreover, due to the setting of the adjustment mechanism, corresponding flow channels need to be provided inside the coating die head, which is easy to generate dead corners of residual materials during the slurry flow process, difficult to clean, and prone to congestion, affecting the uniformity of the discharge. Summary of the Utility Model

[0004] In view of this, this application provides a coating device, which can ensure consistent coating thickness and improve coating quality.

[0005] In order to achieve the above object, this application provides the following technical solutions:

[0006] A coating device, comprising:

[0007] A die head main body, having an upper die head and a lower die head, and a discharge slit formed between the upper die head and the lower die head;

[0008] A plurality of coating flow channels, independently arranged in the upper die head or the lower die head, and all communicating with the discharge slit; and the coating flow channels are inclined with respect to the plane where the discharge slit is located;

[0009] A plurality of metering pumps, connected to the plurality of coating flow channels one-to-one, and capable of measuring and adjusting the material passing amount to make the flow rate of each coating flow channel consistent.

[0010] Optionally, each metering pump is provided with a driving component, and the material passing amount of the metering pump is adjustable by controlling the driving component.

[0011] Optionally, the multiple metering pumps are arranged outside the die head body and are connected to the multiple coating channels one by one through pipelines.

[0012] Optionally, the angle formed by the plane where the discharge slit is located and the coating channel is 20 - 45 degrees.

[0013] Optionally, the coating channel is arranged on the side of the discharge slit away from the lip.

[0014] Optionally, the metering pump is set as a positive displacement pump, a gear pump or a screw pump.

[0015] Optionally, the metering pump is set as a screw pump, including:

[0016] A stator component, which is connected to the coating channel;

[0017] A rotor component, which is rotatably arranged inside the stator component;

[0018] Wherein, the driving component is in transmission connection with the rotor component and can drive the rotor component to rotate relative to the stator component so as to drive the slurry to pass through the stator component.

[0019] Optionally, it includes:

[0020] A total feed channel, which has a feed port and a return port;

[0021] Multiple feed branch channels, which are connected to the total feed channel and are connected to the multiple coating channels one by one;

[0022] Wherein, the feed branch channels and the total feed channel are arranged outside the die head body.

[0023] Optionally, the multiple metering pumps are arranged on the multiple feed branch channels one by one; or, the multiple metering pumps are arranged inside the multiple coating channels one by one.

[0024] Optionally, a flow equalizing cavity is arranged between the upper die head and the lower die head, and the multiple coating channels are connected to the discharge slit through the flow equalizing cavity.

[0025] Optionally, the coating channel is arranged in the upper die head, and a flow equalizing groove is arranged on the lower die head, and the flow equalizing groove is opposite to the outlet of the coating channel to form the flow equalizing cavity between the upper die head and the lower die head.

[0026] Optionally, it includes:

[0027] A control module, which is in communication connection with the multiple metering pumps and can adjust the working parameters of the metering pumps.

[0028] The coating device provided by this application has a coating flow channel inclined relative to the plane where the discharge slit is located, so that the slurry in the coating flow channel enters the discharge slit obliquely. In this way, different from the vertical entry method, the inclined design of the coating flow channel is convenient for cleaning, has fewer dead corners, and the slurry is not easily deposited, which is beneficial to ensuring the uniformity of the discharge. Moreover, through the metering pump, the material passing through each coating flow channel can be adjusted in a closed loop, ensuring that the slurry reaching the lip position of the die head body for each coating flow channel is certain and the same, thereby ensuring that the coating thickness in each area of the lip of the die head body is consistent, achieving coating uniformity and improving the coating quality. Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0030] Figure 1 Working principle diagram of the coating device shown in some embodiments;

[0031] Figure 2 Stereogram of the coating device shown in the first embodiment;

[0032] Figure 3 Cross-sectional view of the coating device shown in the first embodiment;

[0033] Figure 4 Stereogram of the coating device shown in the second embodiment;

[0034] Figure 5 Cross-sectional view of the coating device shown in the second embodiment;

[0035] Figure 6 Stereogram of the coating device shown in some embodiments;

[0036] Figure 7 Stereogram of the upper die head shown in some embodiments.

[0037] In the figure: 1. Upper die head; 2. Lower die head; 3. Gasket; 4. Discharge slit; 5. Coating flow channel; 6. Metering pump; 7. Feed branch channel; 8. Feed main channel; 9. Flow equalizing tank; 10. Coating roller; 11. Polar plate; 12. Coating tank; 13. Driving component. Detailed Embodiments

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0039] As Figures 1-7 shown, the embodiment of the present application provides a coating device, including a die head body, a plurality of coating channels 5 and a plurality of metering pumps 6.

[0040] The die head body has an upper die head 1 and a lower die head 2. A gasket 3 is arranged between the upper die head 1 and the lower die head 2. Through the arrangement of the gasket 3, a discharge slit 4 is formed between the upper die head 1 and the lower die head 2. A lip for coating the electrode sheet is formed on one side of the discharge slit 4, and the other side of the discharge slit 4 is communicated with a plurality of coating channels 5 to form a channel for the slurry to flow out.

[0041] The plurality of coating channels 5 are arranged independently of each other and are arranged in the die head body. Specifically, the coating channels 5 can be arranged in the upper die head 1 or in the lower die head 2. The outlets of the plurality of coating channels 5 are arranged along the width direction of the lip and are communicated with the lip position through the discharge slit 4. During operation, the lip of the die head body faces the electrode sheet 11 on the coating roller 10, and the electrode sheet 11 is coated through the discharge of the plurality of coating channels 5.

[0042] Among them, the coating channel 5 is inclined with respect to the plane where the discharge slit 4 is located (this plane is the contact surface between the upper die head 1 and the lower die head 2, and is also equivalent to the plane where the gasket 3 is located), so that the slurry in the coating channel 5 enters the discharge slit 4 obliquely. In this way, different from the vertical entry method (that is, the case where the coating channel 5 is perpendicular to the plane where the discharge slit 4 is located), the inclination of the coating channel 5 is convenient for cleaning, has fewer dead corners, the slurry is not easy to deposit, and is beneficial to ensuring the uniformity of the discharge.

[0043] Specifically, the included angle formed by the plane where the discharge slit 4 is located and the coating channel 5 is 20 - 45 degrees, and preferably 30 degrees here. In this way, it is beneficial to the flow of the slurry and can avoid the generation of dead corners.

[0044] Moreover, multiple metering pumps 6 are correspondingly connected to multiple coating channels 5. Specifically, the multiple metering pumps 6 and the multiple coating channels 5 are arranged in a one-to-one manner, so that each metering pump 6 can measure and adjust the material passing amount in one coating channel 5, and then the material passing amount in each coating channel 5 can be independently controlled. In this way, through the metering pump 6, the material passing amount in each coating channel 5 can be adjusted in a closed loop, ensuring that the slurry reaching the lip position of the die body in each coating channel 5 is constant and the same, thereby ensuring that the coating thickness in each area of the lip of the die body is consistent, achieving coating uniformity and improving coating quality.

[0045] It should be noted that the above-mentioned metering pump 6 corresponding to and connected to the coating channel 5 can be arranged outside the die body (for example, as Figures 2-5 shown, the metering pump 6 is arranged on the outer wall of the die body and is connected to the coating channel 5 through a pipeline, so that the slurry enters the coating channel 5 after passing through the metering pump 6), or the metering pump 6 can be arranged inside the die body (for example, the metering pump 6 is arranged in the coating channel 5), so that the multiple metering pumps 6 can measure and adjust the material passing amount in the multiple coating channels 5 in a one-to-one manner.

[0046] In some preferred embodiments, the coating channel 5 is arranged on the side of the discharge slit 4 away from the lip, that is, the outlet of the coating channel 5 is connected to the discharge slit 4, and the inlet of the coating channel 5 is farther from the lip position of the coating die than the outlet. By avoiding the position of the lip, the interference of the feed pipeline on the coating work can be reduced.

[0047] A flow equalizing cavity is arranged between the upper die head 1 and the lower die head 2, and this flow equalizing cavity is arranged between the coating channel 5 and the discharge slit 4, so that the multiple coating channels 5 are connected to the discharge slit 4 through the flow equalizing cavity. In this way, through the flow equalizing cavity, the slurry flowing out of the multiple coating channels 5 can be equalized in flow, so that the slurry pressure in the flow equalizing cavity is equal, ensuring better consistency of the slurry thickness flowing out of the discharge slit 4 and the lip.

[0048] In a specific embodiment, the coating channel 5 is arranged in the upper die head 1, so that the inlet of the coating channel 5 is higher than the outlet, facilitating the outflow of the slurry in the coating channel 5. A flow equalizing groove 9 is arranged on the lower die head 2, and the above-mentioned flow equalizing cavity is formed between the flow equalizing groove 9 and the upper die head 1. Among them, the flow equalizing groove 9 is opposite to the position of the outlet of the coating channel 5, which can improve the reliability of the connection between the discharge slit 4 and the flow equalizing cavity, so that after the slurry in the flow equalizing cavity is equalized in flow, it passes through the discharge slit 4 and flows out from the lip.

[0049] In this solution, the coating device includes a main feed channel 8 and a plurality of branch feed channels 7. Among them, the plurality of branch feed channels 7 are all connected to the main feed channel 8, and the plurality of branch feed channels 7 are connected to the plurality of coating channels 5 one-to-one to achieve the diversion of the slurry. The main feed channel 8 has a feed inlet and a return port. When the die head body starts coating, the return port is closed and the feed inlet is opened. The slurry passes through the main feed channel 8, the branch feed channels 7, the coating channels 5, the discharge slit 4 and the lip in sequence. When the die head body stops coating, the return port is opened and the slurry completes the reflux through the return port.

[0050] In some embodiments, as Figures 2-5 shown, the main feed channel 8 and the branch feed channels 7 are arranged as pipeline structures and are arranged outside the coating die head. In this way, the internal structure of the coating die head can be simplified and made smaller, which is convenient for processing and maintenance. Here, the metering pump 6 is preferably arranged on the branch feed channel 7. Under the action of the metering pump 6, the slurry in the branch feed channel 7 is driven to flow, and then the metering pump 6 is connected to the coating channel 5 through a part of the branch feed channels 7. Of course, in other solutions, the metering pump 6 can be arranged on the coating channel 5, or the metering pump 6 can be arranged at the connection position between the coating channel 5 and the branch feed channels 7.

[0051] In other embodiments, the main feed channel 8 and the branch feed channels 7 are arranged as channel structures and are arranged inside the coating die head. In this way, the coating device can have a compact structure, reduce the occupied space, be conducive to reasonable layout, and ensure the integrity of the structure.

[0052] As Figure 1 shown, the main feed channel 8 is connected to the coating tank 12 so that the slurry in the coating tank 12 passes through the main feed channel 8 and the branch feed channels 7 in sequence. Among them, the air pressure is increased in the coating tank 12 so that the coating tank 12 is set as a pressure tank with positive pressure. The positive pressure in the coating tank 12 pushes the slurry to flow, so that there is positive pressure in the main feed channel 8 and each branch feed channel 7 to ensure the fluidity of the slurry supply in each branch feed channel 7. Furthermore, it can be ensured that the feed port of the metering pump 6 will not cause inaccurate flow due to the entry of air bubbles, and the metering pump 6 can be prevented from sucking air.

[0053] In some embodiments, the metering pump 6 is set as a positive displacement pump, a gear pump or a screw pump. Here, the screw pump is preferably used.

[0054] Next, in combination with Figures 2-3A specific description is given for the solution of the screw pump. The metering pump 6 includes a stator component, a rotor component, and a driving component 13. Among them, the stator component has a hollow channel. The stator component is fixed at the middle position of the feed branch channel 7. One end of the stator component is connected to the feed main channel 8 through a part of the pipeline of the feed branch channel 7. The other end of the stator component is connected to the coating flow channel 5 through another part of the feed branch channel 7, so that the slurry can flow through the hollow channel of the stator component, thereby realizing the connection of the feed branch channel 7, the stator component, and the coating flow channel 5. The rotor component is arranged in the hollow channel of the stator component and can rotate relative to the stator component. By the rotation of the rotor component, the slurry can be driven to pass through the hollow channel of the stator component. And when the rotor component does not rotate, the slurry cannot pass through the hollow channel of the stator component. The driving component 13 is fixed to the stator component and is in transmission connection with the rotor component, and is used to drive the rotor component to rotate relative to the stator component, so as to drive the slurry to pass through the hollow channel of the stator component. In this way, through the driving component 13, the material passing amount of the hollow channel of the stator component can be measured and adjusted, and further, it can be ensured that the slurry reaching the lip position of the die head body in each coating flow channel 5 is certain and the same, achieving coating uniformity and improving coating quality.

[0055] Among them, the driving component 13 is set as a servo motor, a variable frequency motor, a proportional motor or a stepping motor. In this way, through the selection of the driving component 13, high-precision pump material control of the metering pump can be realized, and further, the accuracy of coating control can be improved. Preferably, the driving component 13 is set as a servo motor, and the operation of the metering pump is controlled by the servo motor to realize adjustable flow rate.

[0056] In some embodiments, the coating device is provided with a control module. The control module is communicatively connected to a plurality of metering pumps 6 and can adjust the working parameters of the metering pumps 6. Specifically, the control module can be communicatively connected to the driving components 13 of the plurality of metering pumps 6, and can control the working parameters of the plurality of metering pumps 6 according to the obtained working states of the plurality of metering pumps 6, so as to facilitate the closed-loop control and system allocation of the plurality of metering pumps 6.

[0057] Among them, the control module is communicatively connected to the surface density meter, and the control module can adjust the material passing amount of the metering pump 6 according to the coating quality detected by the surface density meter. In this way, a closed-loop control is achieved between the metering pump 6 on each coating channel 5 and the detection element (surface density meter) of the coating system to accurately control the coating quality. During operation, a closed-loop control is achieved between the metering pump 6 and the surface density meter. The quality of the coating is detected by the surface density meter, and then the result is fed back to the metering pump 6 to adjust the material passing amount of the coating channel 5. Alternatively, the slurry can be manually or automatically detected first to measure the solid content of each batch of slurry, and the detection result is sent to the metering pump 6. The metering pump 6 adjusts the material passing amount of the feed branch channel according to the process requirements to adjust the subsequent material passing amount, and then the result after coating is verified and fed back by the surface density meter to further verify the detection result or accurately calibrate the metering pump 6.

[0058] The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, benefits, effects, etc. mentioned in the present application are only examples and not limitations. It cannot be considered that these advantages, benefits, effects, etc. are essential for each embodiment of the present application. Additionally, the specific details disclosed above are only for illustrative and easy-to-understand purposes and not for limitation. These details do not limit the present application to necessarily adopt the above specific details for implementation.

[0059] The block diagrams of the devices, apparatuses, equipment, and systems involved in the present application are only illustrative examples and do not intend to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open-ended terms meaning "including but not limited to" and can be used interchangeably with each other. The word "or" and "and" used herein refer to the word "and / or" and can be used interchangeably with each other unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to" and can be used interchangeably with each other.

[0060] It should also be noted that in the devices, equipment, and methods of the present application, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent solutions of the present application.

[0061] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

[0062] It should be understood that the qualifiers "first", "second", "third", "fourth", "fifth" and "sixth" used in the description of the embodiments of the present application are only for more clearly elaborating the technical solutions and cannot be used to limit the protection scope of the present application.

[0063] The above description has been given for purposes of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A coating device, characterized in that: include: A die body, comprising an upper die and a lower die, and a discharge slit formed between the upper die and the lower die; A plurality of coating flow channels are independently arranged in the upper die head or the lower die head and are all connected to the discharge slit; and the coating flow channels are arranged obliquely relative to the plane where the discharge slit is located; A plurality of metering pumps are connected to the plurality of coating flow channels one by one and can measure and adjust the amount of material flowing so that the flow rate of each coating flow channel is consistent.

2. The coating device according to claim 1, characterized in that: Each metering pump is provided with a driving component, and the material flow rate of the metering pump can be adjusted by controlling the driving component.

3. The coating device according to claim 1, characterized in that: The multiple metering pumps are arranged outside the die body and are connected to the multiple coating flow channels one by one through pipelines.

4. The coating device according to claim 1, characterized in that: The angle formed by the plane where the discharge slit is located and the coating flow channel is 20-45 degrees.

5. The coating device according to claim 1, characterized in that: The coating flow channel is arranged on a side of the discharge slit away from the lip.

6. The coating device according to claim 2, characterized in that: The metering pump is configured as a positive displacement pump, a gear pump or a screw pump.

7. The coating device according to claim 6, characterized in that: The metering pump is configured as a screw pump, comprising: A stator component connected to the coating flow channel; a rotor component rotatably disposed in the stator component; Wherein, the driving component is drivingly connected to the rotor component and can drive the rotor component to rotate relative to the stator component, so as to drive the slurry to pass through the stator component.

8. The coating device according to claim 1, characterized in that: include: A main feed channel, having a feed inlet and a return inlet; A plurality of feed branch channels, connected to the feed main channel and connected one-to-one with the plurality of coating flow channels; Wherein, the feed branch channel and the feed main channel are arranged outside the die body.

9. The coating device according to claim 8, characterized in that: The multiple metering pumps are arranged one by one on the multiple feed branch channels; Alternatively, the plurality of metering pumps are arranged one-to-one in the plurality of coating flow channels.

10. The coating device according to claim 1, characterized in that: A flow-uniform cavity is provided between the upper die head and the lower die head, and the plurality of coating flow channels are connected with the discharge slit through the flow-uniform cavity.

11. The coating device according to claim 10, characterized in that: The coating flow channel is arranged in the upper die head, and the lower die head is provided with a uniform flow groove, and the uniform flow groove is opposite to the outlet of the coating flow channel to form the uniform flow cavity between the upper die head and the lower die head.

12. The coating device according to claim 1, characterized in that: include: The control module is in communication with the plurality of metering pumps and is capable of adjusting working parameters of the metering pumps.

Images