Surface-coating application method, coating apparatus and coating production line for aerogel felt

Abstract

The present patent relates to a surface-coating application method, coating apparatus and coating production line for an aerogel felt. The surface-coating application method for an aerogel felt comprises the following steps: dip-coating, which comprises immersing an aerogel felt into a dip-coating bath, such that the surface of the aerogel felt is infiltrated with paint to form a coating; and coating scraping, which comprises scraping the coating flat. Compared with existing spray-coating and roller-coating methods, the application method, the coating apparatus and the coating production line disclosed in the present embodiment use a dip-then-scrape method, such that an excessive coating is formed on the surface of an aerogel felt, and a coating having uniform thickness and better surface flatness is then obtained after the coating-scraping step. In this way, the thickness of the coating can be adjusted within a larger range. The coating formed by the application method has a strong adhesion capability with the aerogel felt, and does not easily detach from the aerogel felt; in addition, the coating can cover the whole aerogel felt completely, thus effectively preventing the aerogel felt from shedding powder.

Description

Surface coating method, coating equipment and coating production line for aerogel felt Technical Field

[0001] This patent belongs to the field of electric vehicle technology, and particularly relates to a surface coating method for aerogel felt, corresponding coating equipment and coating production line. Background Art

[0002] Electric vehicles are a new type of transportation that uses electric motors instead of traditional engines and power batteries instead of fuel tanks. Compared to traditional fuel vehicles, electric vehicles offer the advantages of reduced carbon emissions, energy conservation, and environmental benefits. However, because electric vehicles use power batteries as their energy source, and power batteries are high-voltage energy storage components, they pose a risk of spontaneous combustion and explosion under the influence of high temperatures or other unstable factors, making electric vehicle safety a persistent concern.

[0003] To address power battery safety issues, existing technologies have developed a series of structural improvements. For example, existing technologies often utilize aerogel's fireproof and heat-insulating properties, using aerogel insulation materials such as aerogel felt to wrap and separate power battery cells.

[0004] Because aerogel felt suffers from powder shedding, it is necessary to perform surface treatment on the aerogel felt before installing it. In the prior art, people often use roller coating or spraying techniques to coat the aerogel surface with an encapsulating coating. However, the inventors of this patent discovered that the aerogel felt obtained using the prior art still suffers from powder shedding. Summary of the Invention

[0005] In order to solve the shortcomings of the prior art, the first aspect of this patent provides a method for applying a surface coating of an aerogel felt, comprising the following steps:

[0006] Dipping step: immersing the aerogel felt into a dipping tank so that its surface is soaked with the coating to form a coating;

[0007] Scraping step: Scraping the coating.

[0008] Preferably, in the dipping step, the single-side coating amount of the aerogel felt is greater than or equal to 0.5 Kg / m2;

[0009] In the scraping step, the coating amount of the coating after scraping is in the range of 0.2 Kg / m2 to 0.8 Kg / m2.

[0010] Preferably, after the dipping step and before the scraping step, the method further comprises:

[0011] Steering step: using a steering roller to transform the movement direction of the aerogel felt from a direction of 30° to 150° to a direction horizontal to the ground;

[0012] After the scraping step, the method further comprises:

[0013] a recovery step of recovering the coating material dripped during the scraping step;

[0014] A filtering step is performed to filter the coating recovered in the recovery step and then return it to the dipping tank.

[0015] Preferably, the aerogel felt is coated via a continuous coating line;

[0016] Before the dipping step, the method further comprises:

[0017] a pulling step of pulling the aerogel felt out of the unloader using a powered roller;

[0018] Flattening step: passing the aerogel felt through a tension roller to keep it flat;

[0019] After the scraping step, the method further comprises:

[0020] Drying step: drying the aerogel felt with the coating;

[0021] After the drying step, the method further comprises:

[0022] Cutting step: cutting the dried aerogel felt into sheets.

[0023] Preferably, before the dipping step, the method further comprises:

[0024] In the hot pressing step, the aerogel felt is hot pressed by a hot pressing device.

[0025] The second aspect of this patent provides an aerogel felt coating device, comprising:

[0026] A dipping tank, used to wet the surface of the aerogel felt immersed in the dipping tank with paint to form a coating;

[0027] The scraping device is arranged at the station after the dipping tank and is used to scrape the coating on the surface of the aerogel felt.

[0028] Preferably, the dipping tank has a dipping station and a recovery station, and the scraping device is arranged above the recovery station to recover the paint dripping from the scraping device;

[0029] The bottom height of the recovery station is greater than the bottom height of the dipping station.

[0030] Preferably, the dipping tank has a dipping station and a recovery station, and the scraping device is arranged above the recovery station to recover the paint dripping from the scraping device;

[0031] The coating equipment also includes:

[0032] A filter screen is arranged in the dipping tank and is used for filtering the coating.

[0033] Preferably, it also includes:

[0034] a partition, disposed in the dipping tank and separating the dipping station from the recovery station;

[0035] A pump is provided in the recovery station and connected to the filter screen. The pump is used to transport the coating filtered by the filter screen back to the dipping station.

[0036] Preferably, the coating device further comprises:

[0037] a channel connecting the dipping station and the recovery station;

[0038] A one-way valve is provided in the passage to limit the flow direction of the coating to a single direction from the dipping station to the recovery station.

[0039] Preferably, it also includes:

[0040] The dipping rollers are arranged in the dipping tank and immersed in the liquid level of the coating. There are at least three dipping rollers in an odd number, so as to guide the aerogel felt into and out of the dipping tank.

[0041] Preferably, the scraping device comprises:

[0042] A scraping assembly and a flat coating assembly are arranged in series, wherein the scraping assembly includes two scraping rods and the flat coating assembly includes two flattening rods;

[0043] The scraping rod is provided with a notch, and the coating thickness of the notch ranges from 40 μm to 150 μm;

[0044] The leveling rod is used to flatten the coating on the surface of the aerogel felt.

[0045] The third aspect of this patent provides an aerogel felt coating production line, comprising:

[0046] The aforementioned coating equipment; and

[0047] A feeding machine is used to place the wound aerogel felt;

[0048] A powered roller, used for pulling the aerogel felt out of the unloader;

[0049] A tension roller, which is arranged between the unloader and the dipping tank and is used to keep the aerogel felt passing through the tension roller in a flat state;

[0050] A steering roller is provided after the dipping roller to change the movement direction of the aerogel felt from a direction of 30° to 150° to a horizontal direction with the ground;

[0051] A drying device, disposed between the doctor blade device and the power roller, for drying the aerogel felt having a coating after doctor blade coating;

[0052] The cutting device is used to cut the dried aerogel felt into sheets.

[0053] Preferably, it also includes:

[0054] The hot pressing equipment is arranged before the coating device and is used for hot pressing the aerogel felt.

[0055] Compared with existing spraying and roller coating methods, the coating method, coating equipment, and coating production line disclosed in this embodiment adopt a dipping-then-scraping method to form an excess coating on the surface of the aerogel felt, and after the scraping step, a coating with uniform thickness and good surface flatness is obtained. In this way, the adjustable range of the coating thickness is larger. The coating formed by this coating method has a strong adhesion ability with the aerogel felt, is not easy to fall off from the aerogel felt, and can completely cover the aerogel felt as a whole, thereby effectively preventing the aerogel felt from falling off. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the existing technical solutions, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0057] FIG1 is a schematic flow chart of a method for coating a surface coating of an aerogel felt in an embodiment of the present invention;

[0058] Figure 2 is a schematic diagram of the structure of the coating production line in the embodiment of this patent;

[0059] Figure 3 is a schematic structural diagram of a dipping tank in an embodiment of the present invention;

[0060] FIG4 is a schematic structural diagram of a wire scraping rod according to an embodiment of the present invention;

[0061] Figure 5 is a schematic diagram of the structure of the dipping tank in another embodiment of this patent

[0062] FIG6 is a schematic structural diagram of a dipping tank in another embodiment of the present invention;

[0063] FIG7 is a schematic structural diagram of a dipping tank in another embodiment of the present invention;

[0064] FIG8 is a schematic structural diagram of a dipping tank in another embodiment of the present invention;

[0065] FIG9 is a schematic structural diagram of a coating production line in another embodiment of the present patent.

[0066] Figure numerals: 1. aerogel felt; 2. dipping tank; 21. dipping station; 22. recovery station; 23. filter screen; 24. pump; 25. dipping roller; 26. channel; 27. one-way valve; 3. scraping device; 31. scraping assembly; 311. scraping rod; 312. notch; 32. flat coating assembly; 4. unloader; 41. material roller; 5. power roller; 6. tension roller; 7. drying equipment; 8. cutting equipment; 9. steering roller; 10. hot pressing equipment. DETAILED DESCRIPTION

[0067] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0068] The inventors of this patent found that in the prior art, people often use roller coating or spraying techniques to coat the surface of aerogel with an encapsulation coating.

[0069] For example, in the prior art patent with publication number CN112079618B and titled "A method for preparing a modified silica aerogel insulation sheet", it is mentioned: "The obtained fiber-reinforced silica wet gel is subjected to aging, solvent replacement and supercritical drying to obtain a silica aerogel insulation sheet. A layer of encapsulation coating is prepared on the surface of the silica aerogel insulation sheet by roller coating, brushing or spraying, and the coating is cured to obtain a modified silica aerogel insulation sheet." For another example, in the prior art patent with publication number CN117071292A and titled "A method for preparing a low-cost fireproof and heat-insulating aerogel felt", it is mentioned: "First, the aerogel powder and glass fiber felt are directly compounded into an aerogel felt, and a roller coating process is used to roll-coat a dense fire-retardant layer on the aerogel layer, and a spraying process is used to spray a hydrophobic modification agent on the fire-retardant layer."

[0070] However, the inventors of this patent found that the aerogel felt obtained by the prior art still suffers from powder shedding.

[0071] In order to solve this technical problem, the inventors of this patent have proposed a new surface coating method for aerogel felt and an aerogel felt coating device. Various non-limiting embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0072] Implementation Method 1

[0073] The first embodiment of this patent discloses a method for applying a surface coating to an aerogel felt, as shown in FIG1 , comprising the following steps:

[0074] Dipping step: immersing the aerogel felt into a dipping tank so that its surface is soaked with the coating to form a coating;

[0075] Scraping step: Scrape the coating flat.

[0076] Correspondingly, the first embodiment of this patent further discloses an aerogel felt coating device, which is applied to the coating production line of the aerogel felt 1, as shown in FIG3 , and includes:

[0077] The dipping tank 2 is used to wet the surface of the aerogel felt 1 immersed in the dipping tank 2 with paint to form a coating;

[0078] The scraping device 3 is arranged at the station after the dipping tank 2 and is used to scrape the coating on the surface of the aerogel felt 1.

[0079] The coating tank 2 is filled with coating, and the aerogel felt 1 is immersed in the coating tank 2 and passes under the liquid surface of the coating in the coating tank 2 so that the aerogel felt 1 can be completely immersed in the coating and form a coating on the surface of the aerogel felt 1 after leaving the liquid surface of the coating.

[0080] After many experiments, the inventors of this patent found that the reason why the powder falling problem always exists in the existing technology is relatively complicated: the thickness of the encapsulation coating is insufficient, the thickness uniformity of the encapsulation coating in various parts, the density of the coating after compaction, and whether there are cavitations in the coating. These may all lead to powder falling of the aerogel felt after encapsulation.

[0081] The inventors have analyzed that the roller coating method used in the prior art often fails to achieve a sufficient coating amount for the encapsulation coating, while the spray coating method can result in poor thickness uniformity and the presence of cavitation. These are likely the reasons for the powder shedding phenomenon in the prior art methods. It is worth mentioning that the aerogel felt itself has a low surface energy, making it difficult for the coating to adhere to the surface of the aerogel felt. This is also one of the objective factors that cause the aerogel felt to shed powder.

[0082] Compared with the existing technology, the technical solution of dip coating combined with scraping coating adopted in this patent has the following advantages:

[0083] 1. In the dipping step, by placing the aerogel felt 1 as a whole into the dipping tank 2, on the one hand, the aerogel felt 1 can be completely immersed in the coating, so that the aerogel felt 1 is wrapped in the coating as a whole, and a coating exceeding the required coating amount is formed on the surface of the aerogel felt 1; on the other hand, the coating formed after the aerogel felt 1 is completely immersed in the coating has a strong adhesion ability with the aerogel felt 1, making it less likely for the coating to fall off from the surface of the aerogel felt 1.

[0084] 2. Compared with the spraying technical solution, the dip coating method can form a coating on both the upper and lower surfaces of the aerogel felt 1 at the same time, and can form an edge seal on the side of the aerogel, thereby effectively improving production efficiency.

[0085] 3. In the scraping step, this patent can effectively eliminate the cavitation formed on the surface of the aerogel by scraping off the excess coating on the aerogel felt 1, so that the coating has a more uniform thickness on the surface of the aerogel felt, that is, better surface flatness, which ensures the consistency of the encapsulation coating on the surface of the aerogel felt.

[0086] 4. Furthermore, during the scraping step, the thickness of the coating formed during the dipping step can be reduced according to actual needs, thereby enabling free adjustment of the coating thickness without requiring large-scale changes to equipment and parameter conditions. Because the aerogel felt 1 is coated with a sufficient amount of coating during the dipping step, the coating thickness can be adjusted over a wide range, providing greater adaptability.

[0087] After testing, the encapsulation coating of the aerogel felt formed by the coating method of this patent has a thicker thickness under simpler process conditions, lower cost and higher production efficiency, and has strong adhesion ability with the encapsulation coating aerogel felt 1, good uniformity, and is not easy to fall off from the surface of the aerogel felt 1, which can better prevent powder loss.

[0088] As a preferred improvement of this embodiment, the dipping equipment may further include:

[0089] The dipping rollers 25 are arranged in the dipping tank 2 and immersed in the liquid level of the coating. There are at least three dipping rollers 25 and they are odd in number, so as to guide the aerogel felt 1 into and out of the dipping tank 2 .

[0090] Specifically, during the dipping process, the aerogel felt enters the dipping tank 2 below the coating liquid level from top to bottom under the guidance of the first dipping roller 25, passes under the first dipping roller 25, and then passes under the last dipping roller 25 and leaves the dipping tank 2 from bottom to top.

[0091] It should be noted that, in addition to the first dipping roller 25 used to guide the aerogel felt 1 into the dipping tank 2 and the last dipping roller 25 used to guide the aerogel felt 1 out of the dipping tank 2, the other dipping rollers 25 located between the two can increase the movement distance of the aerogel felt 1 below the coating liquid level in the dipping tank 2, so as to prolong the time that the aerogel felt 1 is immersed in the coating in the dipping tank 2 and squeeze out the gas inside the aerogel felt 1, thereby ensuring that the aerogel felt 1 can be fully infiltrated by the coating. In the actual production process, the conditions required for the aerogel felt 1 to be fully infiltrated can be determined based on the performance parameters of the aerogel felt 1 itself and the choice of coating. In combination with the movement rate of the aerogel felt 1 in the dipping production line, the number, spacing and other parameters of the dipping rollers 25 can be adjusted.

[0092] Obviously, only one dipping roller 25 may be provided, and the dipping roller 25 is used to guide the aerogel felt 1 into and out of the dipping tank 2. This does not affect the realization of the purpose of the present patent technology.

[0093] As a further preferred improvement to this embodiment, in the dipping step, the coating amount on one side of the aerogel felt 1 is greater than or equal to 0.5 Kg / m2;

[0094] In the blade coating step, the coating amount of the coating after blade coating is in the range of 0.2 kg / m2 to 0.8 kg / m2.

[0095] Experimental data:

[0096] Experimental conclusion:

[0097] It can be seen from the above experimental results that the technical solution of this patent can significantly increase the coating amount of the aerogel felt 1, and due to the increase in the coating amount, the coating surface effect is better and the powder loss is less.

[0098] Implementation Method 2

[0099] The second embodiment of this patent provides a method for applying a surface coating to an aerogel felt, and a coating device suitable for the method. The second embodiment is a further improvement of the first embodiment. The main improvement is that, as shown in Figures 3 and 4, the scraping device 3 includes two structures: a scraping component 31 and a flat coating component 32.

[0100] Specifically, the scraping device 3 includes:

[0101] The scraping assembly 31 and the flat coating assembly 32 are arranged in series. The scraping assembly 31 includes two scraping rods 311 and the flat coating assembly 32 includes two flattening rods. The scraping rods 311 are provided with slots 312. The coating thickness of the slots 312 ranges from 40 μm to 150 μm.

[0102] The leveling rod has a smooth surface and can be used to flatten the coating on the surface of the aerogel felt.

[0103] Specifically, the two scraping rods 311 in the scraping assembly 31 are respectively located on the upper and lower sides of the aerogel felt 1, and are used to scrape the paint on the upper and lower sides of the aerogel felt 1. The two leveling rods in the flat coating assembly 32 are respectively located on the upper and lower sides of the aerogel felt 1, and are used to level the paint on the upper and lower sides of the aerogel felt 1.

[0104] When the aerogel felt 1 passes through the scraping assembly 31, the portion of the coating on the aerogel felt 1 located within the slot 312 is retained, while the portion located outside the slot 312 is squeezed out and dripped by the scraping rod 311, so that after the aerogel felt 1 passes through the scraping assembly 31, the coating on the aerogel felt 1 forms long strips that are evenly spaced along its forward direction. When the aerogel felt 1 passes through the flat coating assembly 32, the long strips of coating that are evenly spaced on the aerogel felt 1 are rolled over by the flat coating rod to be evenly spread to both sides so that the coating forms a coating of uniform thickness on the aerogel felt 1. Since the flat coating rod has a smooth surface, the coating on the aerogel felt 1 has better surface flatness after passing through the flat coating assembly 32, and cavitations that may exist during the dipping process are squeezed out.

[0105] Obviously, by adjusting the depth of the notch 312 and the distance between the two leveling rods, the thickness and coating amount of the coating formed on the surface of the aerogel felt 1 can be simply and conveniently controlled.

[0106] Compared with a simple roller coating solution, since the aerogel felt 1 has been completely soaked in the dipping tank 2, the coating can always maintain good adhesion to the aerogel felt 1 during the scraping process.

[0107] It should be noted that the scraping rod 311 is used to scrape off excess paint on the aerogel felt 1 on the one hand, and on the other hand, the amount of paint per unit area on the aerogel felt 1 can be controlled by adjusting the mesh number of the notch 312, that is, the mesh number of the notch 312 and the amount of paint per unit area on the aerogel felt 1 have a corresponding relationship. In practical applications, since the coating requirements of aerogel felts of different specifications may be different, a variety of scraping rods 311 with different mesh numbers of notches 312 can be prepared according to actual production conditions, and the corresponding scraping rod 311 can be selected according to the required coating amount per unit area of ​​the aerogel felt 1. Accordingly, the interval between the two leveling rods can also be adjusted to accommodate scraping rods 311 with different mesh numbers of notches 312, thereby achieving precise control of the coating thickness.

[0108] Implementation Method 3

[0109] The third embodiment of this patent provides a method for applying a surface coating to an aerogel felt, and a coating device suitable for the method. The third embodiment is a further improvement of the first or second embodiment, the main improvement being that, as shown in FIG5 , a structure is provided that can recover the coating dripping from the scraping device 3 .

[0110] Specifically, the dipping tank 2 has a dipping station 21 and a recovery station 22, and the scraping device 3 is arranged above the recovery station 22 to recover the paint dripping from the scraping device 3;

[0111] The bottom height of the recovery station 22 is greater than the bottom height of the dipping station 21 .

[0112] Correspondingly, the coating coating method may further include:

[0113] The recovery step is to recover the coating material dripped during the scraping step.

[0114] Among them, the dipping station 21 is used to perform the dipping step, that is, to wet the aerogel felt 1. The recovery station 22 is used to recover the paint dripped from the scraping device 3 during the scraping. Moreover, since the bottom height of the trough of the recovery station 22 is greater than the bottom height of the trough of the dipping station 21, the paint recovered in the recovery station 22 can flow from top to bottom into the dipping station 21. In this way, by setting up the recovery station 22, the paint dripped from the scraping device 3 can be recycled and reused, which can not only significantly reduce production costs, but also improve the production environment, reduce waste emissions, and be more environmentally friendly.

[0115] It is worth mentioning that, in order to prevent the coating from coagulating, a stirring device may be provided in the dipping station 21 and / or the recovery station 22 so as to maintain the fluidity of the coating.

[0116] Implementation Method 4

[0117] Since the aerogel felt 1 itself has the characteristic of shedding powder, during the scraping step, when the aerogel felt 1 is scraped flat by the scraping device 3, the powder chips that fall from the aerogel felt 1 will drip into the recovery station 22 together with the scraped paint. These powder chips enter the dipping station 21 through the recycling station and affect the purity of the paint in the dipping station 21. In the short term, this impact is very small and can be ignored, but in the long term, it may lead to a shortened replacement cycle of the paint in the dipping station 21 and may increase costs. Obviously, these powder chips may also affect the quality of the aerogel felt 1 coating.

[0118] The fourth embodiment of this patent provides a method for applying a surface coating to an aerogel felt, and a coating device suitable for the method. The fourth embodiment is a further improvement of the third embodiment, and the main improvement is that, as shown in FIG6 , a filtering device is added.

[0119] Specifically, coating equipment also includes:

[0120] The filter screen 23 is disposed in the dipping tank 2 and separates the dipping station 21 from the recovery station 22 .

[0121] Correspondingly, the coating coating method may further include:

[0122] In the filtration step, the coating recovered in the recovery step is filtered and then returned to the dipping tank 2.

[0123] With this arrangement, the filter 23 can be used to separate the dipping station 21 and the recovery station 22. The paint in the recovery station 22 is filtered through the filter 23 before entering the dipping station 21. The filter 23 is used to filter the paint dust in the recovery station 22 to prevent it from contaminating the paint in the dipping station 21, thereby ensuring the quality of the dipping. In some embodiments, the filter 23 can have a mesh size of 50.

[0124] In other embodiments, the coating apparatus may further include a separator 28, described below, disposed within the dipping tank 2 and separating the dipping station 21 from the recovery station 22. The filter 23 may be disposed on the separator 28. Alternatively, the filter 23 may be detachably mounted on the separator 28. Thus, in practical applications, filters 23 of varying mesh sizes may be selected and replaced depending on the type of aerogel felt 1 and the type of coating.

[0125] It should be noted that, in this embodiment, the power for coating filtration is mainly provided by the liquid level difference between the dipping station 21 and the recovery station 22. However, this method has a low filtration efficiency. Therefore, in order to further improve the filtration efficiency, in other preferred embodiments, as shown in FIG7 , the coating equipment may further include:

[0126] The partition 28 is provided in the dipping tank 2 and separates the dipping station 21 from the recovery station 22:

[0127] The pump 24 is arranged in the recovery station 22 and is connected to the filter 23. The pump 24 is used to transport the paint in the recovery station 22 back to the dipping station 21 through the filter 23. In this embodiment, the dipping tank 2 is separated by a partition 28 to form the dipping station 21 and the recovery station 22; the pump 24 is arranged in the recovery station 22 to extract the paint in the recovery station 22 and is connected to the dipping station 21 through a pipeline; the filter 23 can be arranged at the inlet, outlet or pipeline of the pump 24. Compared with the above embodiment, this embodiment can ensure that the paint can still pass smoothly and return to the dipping station 21 under the selective pressure of the filter, especially the high-mesh HEPA filter, through the arrangement of the pump 24. On the other hand, the pump 24 promotes the continuous exchange and communication of the paint in the recovery station 22 and the dipping station 21, plays a stirring role, and can prevent the paint from solidifying.

[0128] It is worth mentioning that when a pump is provided, since the pump itself can provide the power to drive the paint, the bottom height of the tank of the recovery station 22 does not necessarily need to be set to be greater than the bottom height of the tank of the dipping station 21. This is a major difference between this embodiment and the third embodiment.

[0129] In addition, it should be noted that the aerogel felt 1 not only sheds powder during the process of being scraped by the scraping device 3, but also sheds powder during the dipping process in the dipping station 21. Therefore, the powder shed by the aerogel felt 1 will also affect the purity of the coating in the dipping station 21. Therefore, in some preferred embodiments, as shown in FIG8 , the coating equipment further includes:

[0130] a channel 26 connecting the dipping station 21 and the recovery station 22;

[0131] A one-way valve 27 is provided in the passage 26 to limit the flow direction of the coating to a single direction from the dipping station 21 to the recovery station 22 .

[0132] Through the provision of the channel 26 and the one-way valve 27, the paint in the dipping station 21 can flow unidirectionally from the dipping station 21 to the recovery station 22, which enables the powder falling from the dipping station 21 to flow continuously and unidirectionally with the paint to the recovery station 22, and the paint in the recovery station 22 can use the filter 23 to filter out the powder in the paint, and transport the filtered paint to the dipping station 21. After such a cycle, the paint in the dipping station 21 can be gradually purified, and the content of powder in the paint is maintained at a low level to ensure the quality of the dipping. In some embodiments, as shown in Figure 8, the channel 26 can be directly provided on the partition 28. In other embodiments, one side of the dipping station 21 is also provided with a horizontally extending pipe connected to one side of the recovery station 22 to form the channel 26.

[0133] In some embodiments, as shown in FIG1 , the coating method may further include:

[0134] Steering step: using a steering roller to transform the movement direction of the aerogel felt 1 from a direction of 30° to 150° to a direction horizontal to the ground.

[0135] Accordingly, as shown in FIG3 , the coating production line further includes:

[0136] The steering roller 9 is arranged behind the dipping roller 25 to change the moving direction of the aerogel felt from a direction of 30° to 150° to the ground to a direction horizontal to the ground.

[0137] By setting the steering roller 9, the movement direction of the aerogel felt 1 is changed from bottom to top to a direction horizontal to the ground. On the one hand, in the horizontally moving aerogel felt 1, the gravity direction of the paint thereon is perpendicular to the extension direction of the aerogel felt 1, so that the paint can stay relatively still and stick to the aerogel, so as to ensure that the amount of paint on the aerogel felt 1 is sufficient; on the other hand, it can also prepare the aerogel felt 1 for entering the drying equipment 7.

[0138] It should be noted that, in some embodiments, the steering roller 9 can be arranged after the doctor blade device 3, that is, the aerogel felt 1 is first scraped flat by the doctor blade device 3 and then turned by the rotating roller 9. In this way, since the aerogel felt 1 is scraped flat by the doctor blade device 3, the coating thickness on both sides of the aerogel felt 1 is relatively consistent, but one side of the aerogel felt 1 needs to contact the steering roller 9, which affects the coating thickness on the side of the aerogel felt 1 in contact with the steering roller 9, thereby making the coating thickness on both sides of the aerogel felt 1 inconsistent, which may affect the quality of the coating on the aerogel felt 1.

[0139] Therefore, in some preferred embodiments, as shown in FIG3 , a turning roller 9 can be provided between the scraping device 3 and the dipping roller 25. This allows the aerogel felt 1 to be turned before being scraped flat. On the one hand, this prevents the turning step from affecting the coating thickness on the scraped aerogel felt 1; on the other hand, the aerogel felt 1 can be directly dried in the drying device 7 after passing through the scraping device 3, thereby ensuring that the coating thickness on both sides of the aerogel felt 1 is consistent.

[0140] Implementation Method Five

[0141] The fifth embodiment of this patent provides a method for applying a surface coating to an aerogel felt, and a coating production line suitable for this method. Based on this, as shown in FIG2 , the aerogel felt 1 can be subjected to a series of operations such as coating, drying, and cutting through a continuous coating production line;

[0142] Specifically, as shown in FIG1 , before the dipping step, the following steps are also included:

[0143] A pulling step, using a powered roller to pull the aerogel felt 1 out of the unloading machine;

[0144] Flattening step: passing the aerogel felt 1 through a tension roller to keep it flat;

[0145] After the scraping step, it also includes:

[0146] Drying step: drying the coated aerogel felt 1;

[0147] After the drying step, it also includes:

[0148] Cutting step: cutting the dried aerogel felt 1 into sheets.

[0149] It should be noted that the aerogel mat 1 used in this coating method is a wound aerogel mat 1, that is, a certain length of aerogel mat 1 is wound on a material roller 41. The material roller 41 is placed in a material unloader 4, and the aerogel mat 1 on the material roller 41 can be pulled out for continuous coating. This arrangement realizes continuous supply and unloading, which can effectively improve efficiency.

[0150] Correspondingly, as shown in FIG2 , this embodiment further discloses an aerogel felt coating production line, comprising:

[0151] The aforementioned coating equipment; and

[0152] A discharger 4 is used to place the wound aerogel felt 1;

[0153] A power roller 5 is used to pull the aerogel felt 1 out of the unloader 4;

[0154] Tension roller 6, which is arranged between the unloader 4 and the dipping tank 2, and is used to keep the aerogel felt 1 passing through the tension roller 6 in a flat state;

[0155] The drying device 7 is provided between the doctor blade device 3 and the power roller 5 and is used to dry the aerogel felt 1 having the coating after the doctor blade coating;

[0156] The cutting device 8 is used to cut the dried aerogel felt 1 into sheets.

[0157] It should be noted that in this embodiment, a powered roller 5 is positioned after the drying device 7 to pull the aerogel mat 1. On the one hand, the placement of the powered roller 5 after the drying device 7 does not affect the preceding dipping and doctoring steps. On the other hand, after drying in the drying device 7, the coating on the surface of the aerogel mat 1 has already solidified. At this point, the aerogel mat 1 is pulled by the powered roller 5, and the coating is not easily damaged.

[0158] Implementation Method 6

[0159] The sixth embodiment of this patent provides a method for applying a surface coating to an aerogel felt, and a coating production line suitable for the method. The sixth embodiment is a further improvement of the fifth embodiment, with the main improvement being that, as shown in FIG9 , a hot pressing step is added.

[0160] /

[0161] Specifically, before the dipping step, it also includes:

[0162] In the hot pressing step, the aerogel felt 1 is hot pressed by a hot pressing device 10 .

[0163] Accordingly, the coating production line also includes:

[0164] The hot pressing device 10 is arranged before the doctor blade device 3 and is used to hot press the aerogel felt 1 .

[0165] Specifically, the hot pressing device 10 can be arranged before the tension roller 6 .

[0166] Through the hot pressing step, the aerogel felt 1 is hot pressed by the hot pressing device 10, and the surface of the aerogel felt 1 can be flattened before dipping. On the one hand, this can flatten the surface of the aerogel felt 1 and reduce cavities and bubbles that may be generated during the dipping step. On the other hand, the pre-hot pressing step can reduce the falling of powder chips on the surface of the aerogel felt 1 during the dipping process and reduce impurities in the coating in the dipping tank 2. This not only saves the cost of replacing the coating, but also improves the coating quality.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention rather than to limit them. Although the embodiments of the present invention are described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the embodiments of the present invention can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for coating the surface of an aerogel felt, characterized in that, It includes the following steps: Dip coating step: Immerse the aerogel felt into the dip coating tank to make its surface infiltrated with the coating to form a coating layer; Doctor blade coating step: Level the said coating layer.

2. The method for coating the surface of the aerogel felt according to claim 1, wherein In the said dip coating step, the single-sided coating amount of the aerogel felt is greater than or equal to 0.5 Kg / m2; In the said doctor blade coating step, the coating amount of the coating layer after leveling is in the range of 0.2 Kg / m2 to 0.8 Kg / m2.

3. The method for coating the surface of the aerogel felt according to claim 1, characterized in that, It further includes: Steering step: Use a turning roller to convert the moving direction of the aerogel felt from a direction of 30° to 150° with respect to the ground to a horizontal direction with respect to the ground; And, After the said doctor blade coating step, it further includes: Recovery step: Recover the coating that drips during the doctor blade coating step; Filtration step: Filter the coating recovered in the said recovery step and send it back to the dip coating tank.

4. The method for coating the surface of the aerogel felt according to claim 1, characterized in that The aerogel felt is coated with a coating layer through a continuous coating production line; Before the said dip coating step, it further includes: Traction step: Use a power roller to pull out the aerogel felt from a feeder; Flattening step: Pass the aerogel felt through a tension roller to keep it in a flattened state; After the said doctor blade coating step, it further includes: Drying step: Dry the aerogel felt with a coating layer; After the said drying step, it further includes: Cutting step: Cut the dried aerogel felt to form sheets.

5. The method for coating the surface of the aerogel felt according to claim 1, characterized in that, Before the said dip coating step, it further includes: Hot pressing step: Hot press the aerogel felt through a hot pressing device.

6. A coating device for aerogel felt, characterized in that, It includes: Dip coating tank, which is used to make the surface of the aerogel felt immersed in the dip coating tank infiltrated with the coating to form a coating layer; Doctor blade coating device, which is arranged at the working station after the dip coating tank and is used to level the coating layer on the surface of the aerogel felt.

7. The coating device according to claim 6, characterized in that, The dip coating tank has a dip coating working station and a recovery working station, and the doctor blade coating device is arranged above the recovery working station so as to recover the coating that drips from the doctor blade coating device; The bottom height of the recovery working station is greater than the bottom height of the dip coating working station.

8. The coating device according to claim 6, wherein, The dip coating tank has a dip coating working station and a recovery working station, and the doctor blade coating device is arranged above the recovery working station so as to recover the coating that drips from the doctor blade coating device; The coating equipment further includes: Filter screen, which is arranged in the dip coating tank and is used to filter the coating.

9. The coating device according to claim 8, characterized in that, It further includes: Partition member, which is arranged in the dip coating tank and separates the dip coating working station and the recovery working station; Pump, which is arranged in the recovery working station and is connected to the filter screen, and the pump is used to transport the coating filtered by the filter screen back into the dip coating working station.

10. The coating device according to claim 9, wherein, The coating equipment further includes: Channel, which connects the dip coating working station and the recovery working station; Check valve, which is arranged in the channel and is used to limit the flow direction of the coating to a single direction from the dip coating working station towards the recovery working station.

11. The coating device according to claim 6, wherein, It further includes: Dip coating roller, which is arranged in the dip coating tank and is immersed below the liquid level of the coating, and there are at least three dip coating rollers and the number is odd, and it is used to guide the aerogel felt into and out of the dip coating tank.

12. The coating device according to claim 11, wherein, The doctor blade coating device includes: Continuously arranged doctor blade coating components and flattening components, the doctor blade coating components include two doctor blade bars, and the flattening components include two flattening bars; Notches are formed on the doctor blade bars, and the coating die thickness range of the notches is between 40 μm and 150 μm; The flattening bar is used to flatten the coating on the surface of the aerogel felt.

13. A coating production line for aerogel felt, characterized in that, It includes: The coating equipment according to any one of claims 6 to 12; And A feeding machine for placing the wound aerogel felt; A power roller for pulling out the aerogel felt from the feeding machine; A tension roller, which is arranged between the feeding machine and the dip coating tank, and is used to keep the aerogel felt passing through the tension roller in a flat state; A turning roller, which is arranged after the dip coating roller, and converts the movement direction of the aerogel felt from a direction of 30° to 150° with the ground into a horizontal direction with the ground; A drying device, which is arranged between the scraping device and the power roller, and is used to dry the aerogel felt with a coating after scraping; A cutting device for cutting the dried aerogel felt into sheets.

14. The coating production line according to claim 13, wherein It further includes: A hot pressing device, which is arranged before the scraping device and is used to perform a hot pressing operation on the aerogel felt.

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