Coating device

Abstract

The utility model relates to the technical field of battery manufacturing, and provides a coating device which comprises a slurry supply mechanism, a coating mechanism and a stirring mechanism, the slurry supply mechanism is used for supplying slurry; the coating mechanism is connected with the slurry supply mechanism through a slurry supply pipeline; the stirring mechanism is arranged at the upstream of the coating mechanism and is used for mixing and stirring slurry which is about to enter the coating mechanism; the coating mechanism comprises a scraper piece; a slurry storage bin and a slurry outlet communicated with the slurry storage bin are arranged in the scraper piece; the scraper piece is further provided with a backflow opening, and the slurry storage bin can make slurry flow back to the stirring mechanism in a one-way mode through the backflow opening. According to the coating device, slurry is fully stirred and mixed through the stirring mechanism, it is ensured that components and viscosity of the slurry are uniform, the printing quality is improved, a backflow opening is further formed in the scraper piece, the slurry in the scraper piece can flow back to the stirring mechanism in a one-way mode, circular flowing of the slurry is achieved, and the printing quality is improved. Slurry can be effectively prevented from being accumulated and dried in the scraper cavity, and the service life of the scraper is prolonged.

Description

Technical Field

[0001] This patent relates to the field of photovoltaic cell manufacturing equipment, and in particular to a slurry coating device. Background Technology

[0002] In the solar cell manufacturing process, uniform printing of the paste is a crucial step. Traditional paste coating equipment typically consists of a paste tank, a doctor blade, and a pneumatic system. The pneumatic system applies pressure to the paste tank, forcing the paste into the closed doctor blade chamber. Then, the linear motion of the doctor blade evenly prints the paste onto the corresponding film or silicon wafer. While this method improves printing efficiency, it still has some problems. For example, after the paste in the tank is used up, a new paste tank needs to be replaced, or paste needs to be added. Moreover, during the process of replacing the paste tank or adding paste, the paste coating equipment needs to be shut down. It can only be restarted after the new paste tank has been replaced or the paste has been added, which significantly affects the working efficiency of the coating equipment.

[0003] In view of this, there is an urgent need in the market for a new type of slurry coating device to solve the problem that the slurry tank of the slurry coating device needs to be shut down for replacement after it is used up, which greatly affects the working efficiency of the coating device. Utility Model Content

[0004] This disclosure provides a coating apparatus to address the problem in related technologies where the slurry tank of a slurry coating apparatus needs to be shut down for replacement after use, which significantly affects the working efficiency of the coating apparatus.

[0005] The coating apparatus provided in this embodiment includes a slurry supply mechanism and a coating mechanism;

[0006] The coating mechanism is connected to the slurry supply mechanism and is used to coat the workpiece with the slurry supplied by the slurry supply mechanism;

[0007] The slurry supply mechanism includes a slurry tank, a buffer tank, a first pressurizing device, and a second pressurizing device.

[0008] The first pressurizing device is electrically connected to the slurry tank and is used to pressurize and discharge the slurry from the slurry tank;

[0009] The inlet of the buffer tank is adjustablely connected to the slurry tank via a control valve, and the outlet of the buffer tank is connected to the coating mechanism via a slurry supply pipe.

[0010] The second pressurizing device is electrically connected to the buffer tank and is used to pressurize and discharge the slurry in the buffer tank;

[0011] When the control valve is open, the slurry in the slurry tank can enter the buffer tank in one direction, and the second pressurizing device is in standby mode.

[0012] When the control valve is closed, the slurry tank is blocked from the buffer tank, and the second pressurizing device is in a pressurizing state.

[0013] In one embodiment, the coating apparatus further includes a controller and a detector;

[0014] The detector is installed in the slurry tank and is used to detect the pressure or liquid level information in the slurry tank;

[0015] The controller is electrically connected to the detector, the control valve, and the second pressurizing device, and can switch the state of the control valve and the second pressurizing device according to the detection information of the detector.

[0016] In one embodiment, the coating apparatus further includes a stirring mechanism;

[0017] The stirring mechanism is located between the slurry supply mechanism and the coating mechanism, and is used to mix and stir the slurry that is about to enter the coating mechanism;

[0018] In one embodiment, the coating mechanism includes a scraper;

[0019] The scraper has a slurry storage chamber inside and a slurry outlet communicating with the slurry storage chamber;

[0020] The scraper is also provided with a return port, and the slurry storage tank can unidirectionally return the slurry to the stirring mechanism through the return port.

[0021] In one possible implementation, the coating mechanism further includes a transfer compartment;

[0022] One end of the transfer chamber is connected to the slurry supply mechanism via the slurry supply pipe, and the other end is connected to the scraper via the slurry supply pipe.

[0023] The stirring mechanism is used to mix and stir the slurry in the transfer bin;

[0024] The return port in the scraper component is in unidirectional communication with the transfer chamber.

[0025] In one embodiment, the stirring mechanism includes a circulating stirring pump;

[0026] One end of the circulating mixing pump is located at least partially in the transfer chamber and is capable of mixing the slurry in the transfer chamber.

[0027] In one embodiment, grouting chambers are respectively provided at both ends of the top side of the scraper;

[0028] The transfer chamber is connected to the two grouting chambers via two grout supply pipes.

[0029] In one embodiment, the transfer compartment is located at the center of the top side of the scraper.

[0030] Furthermore, the return port is located at the top center of the scraper and is unidirectionally connected to the bottom of the transfer compartment.

[0031] In one embodiment, the scraper further includes a first scraper blade and a second scraper blade;

[0032] The first scraper blade and the second scraper blade are disposed on the bottom side of the scraper component by means of a fixing member in a mutually inclined and close manner;

[0033] The first scraper blade and the second scraper blade are spaced apart to form the slurry outlet.

[0034] In one embodiment, the coating mechanism further includes a linear motion device;

[0035] The linear motion device is connected to the scraper component for driving the scraper component to move linearly along the surface of the film to be coated.

[0036] The technical solution provided in this disclosure has the following advantages compared with related technologies:

[0037] The coating apparatus provided in this embodiment of the present disclosure has a buffer tank located downstream of the slurry tank. A regulating valve provides one-way adjustable communication between the buffer tank and the buffer tank. An adjustable second pressurizing device is connected to the buffer tank. When a new slurry tank needs to be replaced or slurry needs to be added, the regulating valve can temporarily disconnect the slurry tank from the buffer tank, allowing the empty slurry tank to be removed directly or slurry to be added directly to the empty tank. Furthermore, the second pressurizing device can enter a pressurized working state, allowing the slurry buffered in the buffer tank to continue to be discharged and supplied to the coating mechanism, ensuring a continuous supply of slurry to the coating mechanism. This eliminates the need to stop the machine during slurry tank replacement or slurry addition, effectively solving the problem in related technologies where the coating apparatus requires machine shutdown for replacement after slurry tank use, significantly impacting coating efficiency.

[0038] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0039] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings. Several embodiments of this disclosure are illustrated in the drawings by way of example and not limitation, in which:

[0040] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0041] Figure 1 A schematic diagram of the coating apparatus provided in an embodiment of this disclosure is shown;

[0042] Figure 2 A schematic diagram of the slurry supply mechanism in the coating apparatus provided in an embodiment of this disclosure is shown;

[0043] Figure 3 A diagram showing the slurry flow direction of the coating apparatus provided in an embodiment of this disclosure is shown;

[0044] Figure 4 A schematic diagram of the coating mechanism in the coating apparatus provided in the embodiments of this disclosure is shown;

[0045] Figure 5 A cross-sectional view of the coating mechanism in the coating apparatus provided in an embodiment of this disclosure is shown;

[0046] Figure 6 A schematic diagram of the stirring mechanism in the coating apparatus provided in an embodiment of this disclosure is shown.

[0047] Explanation of the numbers in the diagram: 1. Slurry supply mechanism; 11. Slurry tank; 12. Buffer tank; 121. Control valve; 13. First pressurization device; 14. Second pressurization device;

[0048] 2. Coating mechanism; 21. Scraper blade; 211. Slurry storage bin; 212. Slurry outlet; 213. Return outlet; 214. Grouting bin; 215. First scraper blade; 216. Second scraper blade; 22. Transfer bin;

[0049] 3. Stirring mechanism. Detailed Implementation

[0050] To make the objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0051] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0052] Combination Figure 1 and Figure 2 As shown, this embodiment of the present disclosure provides a coating device, which includes a slurry supply mechanism 1 and a coating mechanism 2; the coating mechanism 2 is connected to the slurry supply mechanism 1 and is used to coat the workpiece with the slurry supplied by the slurry supply mechanism 1; wherein, the slurry supply mechanism 1 includes a slurry tank 11, a buffer tank 12, a first pressurizing device 13 and a second pressurizing device 14; the first pressurizing device 13 is electrically connected to the slurry tank 11 and is used to pressurize and discharge the slurry in the slurry tank 11; the inlet end of the buffer tank 12 is connected to the buffer tank 12 via a regulating valve 121. The slurry tank 11 is adjustable and conductive, and the outlet end of the buffer tank 12 is connected to the coating mechanism 2 through a slurry supply pipe; the second pressurizing device 14 is conductively connected to the buffer tank 12 and is used to pressurize and discharge the slurry in the buffer tank 12; when the control valve 121 is open, the slurry in the slurry tank 11 can enter the buffer tank 12 in one direction, and the second pressurizing device 14 is in standby mode; when the control valve 121 is closed, the slurry tank 11 and the buffer tank 12 are blocked, and the second pressurizing device 14 is in pressurizing mode.

[0053] The coating apparatus provided in this embodiment can be specifically applied to the brushing and coating of slurry in the battery cell manufacturing process, but is not limited to this application. The usage process will be described using this as an example.

[0054] In actual operation, the slurry tank 11 in the slurry supply mechanism 1 is pressurized by the first pressurizing device 13, and the slurry in the slurry tank 11 is first discharged to the buffer tank 12, and then the slurry is discharged to the coating mechanism 2 through the buffer tank 12. The coating of the slurry can be achieved by moving in a straight line along the battery cell.

[0055] Furthermore, when the slurry in the slurry tank 11 is completely drained and a new slurry tank 11 needs to be replaced or slurry needs to be added, the control valve 121 at the inlet of the buffer tank 12 can be temporarily closed to temporarily block the slurry tank 11 from the buffer tank 12. This allows the empty slurry tank 11 to be removed and replaced with a new one, or slurry to be added directly to the empty slurry tank 11. During this process, the second pressurizing device 14 can enter the pressurizing state, thereby ensuring that the slurry buffered in the buffer tank 12 can continue to be discharged and supplied to the coating mechanism 2. This ensures that the coating mechanism 2 still has slurry to coat normally during the replacement of the slurry tank 11 or the addition of slurry, thus avoiding coating interruption of the coating mechanism 2. Moreover, once the slurry tank 11 has been replaced or replenished, the control valve 121 can be switched to the open state, and the second pressurizing device 14 can be switched to the standby state. At this time, the slurry in the slurry tank 11 can continue to enter the buffer tank 12 in one direction and replenish the buffer tank 12. In addition to replenishing the slurry, the buffer tank 12 can also discharge the slurry to the coating mechanism 2 for normal coating.

[0056] In addition, it is worth noting that the first pressurizing device 13 and the second pressurizing device 14 mentioned above can both be configured as pressurizing air pumps. In this way, compressed air can be injected into the slurry tank 11 or the buffer tank 12 by the pressurizing air pumps to ensure that the slurry in the slurry tank 11 and the buffer tank 12 can be discharged efficiently. The control valve 121 mentioned above can be specifically configured as a one-way pressure valve or a one-way liquid level valve. When the pressure or liquid level of the slurry tank 11 is lower than the preset threshold, the control valve 121 can switch from the one-way open state to the closed state.

[0057] In summary, the coating apparatus provided in this embodiment of the present disclosure, by setting a buffer tank 12 downstream of the slurry tank 11 and connecting it to the buffer tank 12 via a regulating valve 121, and connecting the buffer tank 12 to an adjustable second pressurizing device 14, allows the regulating valve 121 to temporarily disconnect the slurry tank 11 from the buffer tank 12 when a new slurry tank 11 needs to be replaced or when slurry needs to be added. This allows the empty slurry tank 11 to be removed directly or slurry to be added directly to the empty slurry tank 11. Moreover, the second pressurizing device 14 can enter a working pressurizing state, allowing the slurry buffered in the buffer tank 12 to continue to be discharged and supplied to the coating mechanism 2, ensuring that the coating mechanism 2 continues to have a continuous supply of slurry. This eliminates the need to stop the machine when replacing the slurry tank 11 or adding slurry, thus effectively solving the problem in related technologies where the coating apparatus requires a shutdown for replacement after the slurry tank is used up, which significantly affects coating efficiency.

[0058] In one embodiment, the coating apparatus further includes a controller and a detector; the detector is disposed in the slurry tank 11 and is used to detect the pressure information or liquid level information in the slurry tank 11; the controller is electrically connected to the detector, the control valve 121 and the second pressurizing device 14 respectively, and can switch the state of the control valve 121 and the second pressurizing device 14 according to the detection information of the detector.

[0059] The aforementioned controller can be specifically, but not limited to, a PLC programmable logic controller, and the detector can be specifically, but not limited to, a level detector or a pressure detector. When the slurry in the slurry tank 11 is emptied, the level or pressure in the slurry tank 11 will rapidly drop to zero, triggering the detector. Based on the detector's trigger detection information, the controller can then quickly switch the control valve 121 to the closed state and switch the second pressurizing device 14 to the working pressurizing state.

[0060] The specific configuration of the controller and detector described above can significantly improve the response sensitivity of the control valve 121 and the second pressurizing device 14, so that when the coating device needs to replace the slurry tank 11 or add slurry, it can immediately disconnect the slurry tank 11 from the buffer tank 12 and promptly discharge the buffered slurry in the buffer tank 12.

[0061] In one embodiment, the coating apparatus further includes a stirring mechanism 3; the stirring mechanism 3 is disposed between the slurry supply mechanism 1 and the coating mechanism 2, and is used to mix and stir the slurry that is about to enter the coating mechanism 2.

[0062] Specifically, in combination Figure 3 and Figure 4 In further detail, a stirring mechanism 3 is provided between the slurry supply mechanism 1 and the coating mechanism 2. The stirring mechanism 3 can be located adjacent to the upstream of the coating mechanism 2, and can be configured as a spiral stirrer, stirring blade, stirring circulation pump, etc., to mix and stir the slurry before it enters the coating mechanism 2.

[0063] In this way, the paste can be fully mixed and stirred by the stirring mechanism 3 before entering the coating mechanism 2, so that the coating mechanism 2 can more evenly coat the paste onto the surface of the battery cell and improve the printing effect.

[0064] In one embodiment, the coating mechanism 2 includes a scraper 21, the scraper 21 having a slurry storage chamber 211 inside and a slurry outlet 212 communicating with the slurry storage chamber 211; the scraper 21 also has a return port 213, and the slurry storage chamber 211 can unidirectionally return the slurry to the mixing mechanism 3 through the return port 213.

[0065] Specifically, in combination Figure 3 , Figure 4 and Figure 5 In further detail, during operation, the slurry supply mechanism 1 pumps the slurry to the mixing mechanism 3. The mixing mechanism 3 thoroughly mixes the slurry before it enters the slurry storage chamber 211 of the doctor blade 21. The doctor blade 21 can move along the surface of the battery cell, thus uniformly coating and printing the slurry onto the corresponding battery cell. Moreover, since the doctor blade 21 is also provided with a return port 213, and the slurry storage chamber 211 can unidirectionally return the slurry to the mixing mechanism 3 through the return port 213, the slurry can be circulated, effectively preventing the slurry from accumulating and drying in the doctor blade chamber, thereby extending the service life of the doctor blade and improving the printing effect.

[0066] In one embodiment, the coating mechanism 2 further includes a transfer chamber 22; one end of the transfer chamber 22 is connected to the slurry supply mechanism 1 via a slurry supply pipe, and the other end is connected to the scraper 21 via a slurry supply pipe; the stirring mechanism 3 is used to mix and stir the slurry in the transfer chamber 22; the return port 213 in the scraper 21 is connected to the transfer chamber 22 in a one-way manner.

[0067] Specifically, in combination Figure 4In further detail, the coating mechanism 2 also includes a transfer chamber 22, which is located between the slurry supply mechanism 1 and the scraper 21, connected via a slurry supply pipe. The mixing mechanism 3 can be at least partially located inside the transfer chamber 22, for example, using a blade agitator or a circulating mixing pump, enabling the transfer chamber 22 to perform secondary mixing of the slurry. Furthermore, the return port 213 can be connected to the transfer chamber 22 via a one-way valve, allowing only slurry to flow back from the scraper 21 to the transfer chamber 22. This allows the transfer chamber 22 to balance fluctuations in the slurry supply pressure, ensuring stable slurry flow, and also to allow slurry from the scraper 21 to flow back and undergo secondary mixing, further optimizing slurry uniformity.

[0068] In one embodiment, the stirring mechanism 3 includes a circulating stirring pump; one end of the circulating stirring pump is at least partially located in the transfer chamber 22 and is capable of stirring the slurry in the transfer chamber 22.

[0069] Specifically, in combination Figure 6 In further detail, the mixing mechanism 3 is specifically configured to include a circulating mixing pump, with the inlet end of the pump extending into the top of the transfer chamber 22 and the outlet end connected to the top of the transfer chamber 22. Thus, when the circulating mixing pump is running, the slurry is drawn in from the bottom of the transfer chamber 22, mixed by the impeller inside the pump, and then reinjected into the slurry supply pipe, forming a mixing circuit. This allows for thorough and efficient mixing of the slurry in the transfer chamber 22.

[0070] In one embodiment, the top two ends of the scraper 21 are respectively provided with grouting chambers 214; the transfer chamber 22 is connected to the two grouting chambers 214 through two grout supply pipes.

[0071] Specifically, in combination Figure 4 and Figure 6 In further detail, a grouting chamber 214 is provided at each of the two ends of the top side of the scraper 21, and the transfer chamber 22 is connected to the two grouting chambers 214 through two independent grout supply pipes. In this way, the grout in the transfer chamber 22 can enter the two ends of the grout storage chamber 211 in the scraper 21 in two symmetrical ways, and after flowing towards each other in the grout storage chamber 211, it can be better returned to the transfer chamber 22 through the return port 213.

[0072] The specific arrangement of the grouting chamber 214 described above can symmetrically distribute the grout in the transfer chamber 22, thereby better balancing the internal pressure of the grout storage chamber 211 in the scraper component 21, and enabling the grout outlet 212 in the scraper component 21 to discharge grout more evenly.

[0073] In one embodiment, the transfer chamber 22 is disposed at the top center of the scraper 21; and the return port 213 is correspondingly opened at the top center of the scraper 21 and is unidirectionally connected to the bottom of the transfer chamber 22.

[0074] Specifically, in combination Figure 4 and Figure 5 In further detail, the transfer chamber 22 is located at the top center of the scraper 21, and the return port 213 is correspondingly located at the top center of the scraper 21, connected to the bottom of the transfer chamber 22 via a one-way valve. Thus, when slurry flows back, it can enter the transfer chamber 22 from top to bottom through the central return port 213, mix with new slurry, and then be pumped back into the grouting chamber 214.

[0075] The specific arrangement of the transfer chamber 22 and the return port 213 allows the slurry accumulated in the middle of the scraper 21 to flow back upward to the transfer chamber 22 for secondary and efficient mixing.

[0076] In one embodiment, the scraper component 21 further includes a first scraper blade 215 and a second scraper blade 216; the first scraper blade 215 and the second scraper blade 216 are disposed on the bottom side of the scraper component 21 by means of a fixing member in a mutually inclined and close manner; and the first scraper blade 215 and the second scraper blade 216 form a slurry outlet 212 at intervals.

[0077] Specifically, in combination Figure 4 and Figure 5 In further detail, a first scraper blade 215 and a second scraper blade 216 are provided in the scraper component 21. The first scraper blade 215 and the second scraper blade 216 are provided on the bottom side of the scraper component 21 by means of a fixing member, in a way that they are inclined and close to each other. In this way, when the scraper component 21 moves back and forth in a linear motion in one direction, the first scraper blade 215 and the second scraper blade 216 can respectively play the role of coating and smoothing in the direction of movement of the scraper component 21.

[0078] Furthermore, the first scraper blade 215 and the second scraper blade 216 can be arranged flush with each other to form a strip-shaped slurry outlet 212 for the slurry in the scraper 21 to flow out. The first scraper blade 215 and the second scraper blade 216 can also abut against the surface of the workpiece to be coated, forming a closed scraper structure.

[0079] In one embodiment, the coating mechanism 2 further includes a linear motion device; the linear motion device is connected to the scraper 21 for driving the scraper 21 to move linearly along the surface of the film to be coated.

[0080] The linear motion device in the coating mechanism 2 can be specifically configured as a servo motor and a linear guide rail. The servo motor is used to drive the scraper 21 to move horizontally along the guide rail, and the moving speed is adjustable. The linear guide rail is used to further guide and limit the movement trajectory of the scraper 21.

[0081] The aforementioned linear motion device can precisely control the moving speed of the scraper 21 to adapt to the coating requirements of different slurry viscosities.

[0082] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0083] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A coating device, characterized in that The coating device comprises a slurry supply mechanism (1) and a coating mechanism (2); The coating mechanism (2) is connected with the slurry supply mechanism (1) and is used for coating the slurry supplied by the slurry supply mechanism (1) on a workpiece; The slurry supply mechanism (1) comprises a slurry tank (11), a buffer tank (12), a first pressurizing device (13) and a second pressurizing device (14); The first pressurizing device (13) is in conductive connection with the slurry tank (11) and is used for pressurizing and discharging the slurry in the slurry tank (11); The inlet end of the buffer tank (12) is in adjustable conductive connection with the slurry tank (11) through a regulating valve (121), and the outlet end of the buffer tank (12) is connected with the coating mechanism (2) through a slurry supply pipeline; The second pressurizing device (14) is in conductive connection with the buffer tank (12) and is used for pressurizing and discharging the slurry in the buffer tank (12); When the regulating valve (121) is in an open state, the slurry in the slurry tank (11) can enter the buffer tank (12) in a unidirectional manner, and the second pressurizing device (14) is in a standby state; When the regulating valve (121) is in a closed state, the slurry tank (11) is blocked with the buffer tank (12), and the second pressurizing device (14) is in a pressurizing state.

2. The coating device of claim 1, wherein The coating device further comprises a controller and a detector; The detector is arranged in the slurry tank (11) and is used for detecting pressure information or liquid level information in the slurry tank (11); The controller is electrically connected with the detector, the regulating valve (121) and the second pressurizing device (14) respectively and can correspondingly switch the states of the regulating valve (121) and the second pressurizing device (14) according to the detection information of the detector.

3. The coating device according to claim 1 or 2, characterized in that The coating device further comprises a stirring mechanism (3); The stirring mechanism (3) is arranged between the slurry supply mechanism (1) and the coating mechanism (2) and is used for mixing and stirring the slurry about to enter the coating mechanism (2).

4. The coating device of claim 3, wherein The coating mechanism (2) comprises a scraper (21); The scraper (21) has a slurry storage bin (211) inside and a slurry outlet (212) in conductive connection with the slurry storage bin (211); The scraper (21) is further provided with a backflow port (213), and the slurry storage bin (211) can unidirectionally backflow the slurry to the stirring mechanism (3) through the backflow port (213).

5. The coating device of claim 4, wherein The coating mechanism (2) further comprises a transfer bin (22); One end of the transfer bin (22) is in conductive connection with the slurry supply mechanism (1) through the slurry supply pipeline, and the other end is in conductive connection with the scraper (21) through the slurry supply pipeline; The stirring mechanism (3) is used for mixing and stirring the slurry in the transfer bin (22); The backflow port (213) in the scraper (21) is in unidirectional conductive connection with the transfer bin (22).

6. The coating device of claim 5, wherein The stirring mechanism (3) comprises a circulating stirring pump; One end of the circulating stirring pump is at least partially located in the transfer bin (22) and can stir the slurry in the transfer bin (22).

7. The coating device of claim 5, wherein The top side of the scraper (21) is further provided with a slurry injection bin (214) at both ends respectively; The transfer bin (22) is connected with two grouting bins (214) through two grouting pipes respectively.

8. The coating device of claim 5, wherein The transfer bin (22) is arranged at the top middle part of the scraper (21). The return flow port (213) is arranged at the top middle part of the scraper (21) and is connected with the bottom of the transfer bin (22) in a one-way manner.

9. The coating device of claim 4, wherein The scraper (21) further comprises a first scraper blade (215) and a second scraper blade (216). The first scraper blade (215) and the second scraper blade (216) are arranged on the bottom side of the scraper (21) in a mutual inclined manner through a fixing member. The first scraper blade (215) and the second scraper blade (216) are spaced to form the grouting port (212).

10. The coating device of claim 4, wherein The coating mechanism (2) further comprises a linear motion device. The linear motion device is in transmission connection with the scraper (21) and is used for driving the scraper (21) to move linearly along the surface of the workpiece to be coated.

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