Coating equipment for manufacturing aramid paper and preparation method for improving density and dielectric strength of aramid paper

Abstract

The invention discloses coating equipment for manufacturing aramid paper and a preparation method for improving the density and dielectric strength of the aramid paper. According to the coating equipment, a swing arm type tension roller, a circulating type drying system and a ceramic anilox roller are additionally arranged, a leading-in part and a leading-out part are additionally arranged on three parts of a traditional coating machine, and in the leading-in part and the leading-out part, compression rollers are used as tension isolation to divide multiple sections of tension structures, so that the stability, the driving speed and the coating uniformity in the operation process are effectively improved. The tension is monitored in real time through the position of the swing arm of the swing arm type tension roller, and the tension stability is guaranteed. The structure that the ceramic anilox roller is matched with the liquid delivery roller is adopted, the coating amount can be relatively stably reduced by increasing the mesh number of the anilox roller, and the coating uniformity is improved; and by adopting the circulating air drying system, the drying time is greatly shortened, and the overall vehicle speed is increased. According to the invention, the problems of poor paper surface flatness, excessive internal pores and high water absorption and air permeability of aramid paper can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of aramid paper manufacturing, in particular to coating equipment for manufacturing aramid paper and a preparation method for improving the density and dielectric strength of aramid paper. Background Art

[0002] In recent years, aramid paper has been widely used in the insulation of automobiles, motors, transformers, and electronic appliances. It can also be further processed into honeycomb structure materials as an important component of aircraft, high-speed rail, and motor vehicles. The physical performance of aramid paper, such as dielectric constant and air permeability, determines its practical application level.

[0003] For different application scenarios, the thickness of aramid insulation paper ranges from the thinnest 0.03mm to the thickest 0.76mm. Due to various reasons, the papermaking process may cause more pores and reduce its physical properties. The traditional coating of aramid paper with a wet water machine is prone to problems such as unstable tension control and uneven coating. It is difficult to ensure consistent coating amount, resulting in low flatness, decreased dielectric strength and density of the aramid paper. In addition, when the traditional coating machine coats the aramid stock solution, the tension provided by the differential method at the two ends of the winding and unwinding is unstable due to the downward pressure of the pressure roller and the rotation of the anilox roller, which causes creases in the paper during the coating process, and also causes low flatness, decreased dielectric strength and density of the aramid paper. Summary of the invention

[0004] Due to the above defects in the prior art, the present invention provides a coating device for manufacturing aramid paper and a preparation method for improving the density and dielectric strength of aramid paper, which solves the problems of poor surface flatness, excessive internal pores, high water absorption and air permeability of aramid paper.

[0005] To achieve the above-mentioned object, in a first aspect, the present invention provides a coating device for manufacturing aramid paper, comprising an unwinding mechanism, a coating system and a winding mechanism; the aramid paper without flatness treatment after hot pressing enters the coating device through the unwinding mechanism;

[0006] An introduction mechanism is provided between the unwinding mechanism and the coating system; a lead-out mechanism is provided between the coating system and the winding mechanism; the aramid paper is introduced into the coating system after passing through the first tension swing roller, the first arc roller, the first top roller, the first pressure roller, and the second tension swing roller in the introduction mechanism in sequence; the first pressure roller is used as a tension isolation to divide the multi-section tension structure;

[0007] The coating system includes an embossing roller, an embossing rubber roller, a ceramic anilox roller, a liquid transfer roller, a liquid doctor blade, and a circulating air drying system; the liquid transfer roller transports aramid stock solution from the aramid stock solution pool to the ceramic anilox roller; the aramid paper passes through the gap between the ceramic anilox roller and the embossing rubber roller for coating, and then enters the circulating air drying system for drying;

[0008] The aramid paper is led out of the coating system through the third tension swing roller, the second arc roller, the second top roller, the second pressure roller and the fourth tension swing roller in the lead-out mechanism in sequence, and enters the winding mechanism.

[0009] Compared with the traditional coating machinery, the present invention newly adds a swing-arm tension roller, and the tension is monitored in real time by the position of the swing arm of the swing-arm tension roller, so as to ensure the stability of the tension and eliminate the tension change. The coating equipment adds the introduction and lead-out parts to the three parts of the traditional coating machinery, and the pressure roller is used as the tension isolation to divide the tension structure into multiple sections: unwinding introduction; introduction and coating; coating-drying-lead-out; lead-out and winding, so as to improve the stability of the tension. Compared with the metal anilox roller of the traditional coating device placed in the liquid tank, the rotation of the anilox roller and the scraping of the liquid into the liquid tank will generate foam, and the metal anilox roller has poor wettability to the coating material. By replacing it with a ceramic anilox roller with higher wettability, the coating uniformity is improved.

[0010] Furthermore, the sides of the first tension swing roller and the fourth tension swing roller are respectively provided with matching tension sensors and swing roller cylinders for tension control.

[0011] This arrangement ensures that the tension is stable and eliminates tension variations by keeping the cylinder pressure consistent with the set tension.

[0012] Furthermore, the unwinding mechanism and the rewinding mechanism respectively include a reel and an air shaft arranged at the center thereof, a driving motor and a driver thereof.

[0013] Furthermore, the introduction mechanism or the lead-out mechanism also includes a traction mechanism, and a plurality of guide rollers are arranged between the traction mechanism and the coating system; the embossing roller adopts a swing-arm type embossing mechanism.

[0014] Furthermore, the traction mechanism includes a traction motor, a traction steel roller, a traction rubber roller, and a cylinder; when the main motor is started, the traction motor is started, and the traction steel roller is driven to rotate through the coupling sleeve; when the coating is started, the cylinder piston rod moves downward, the traction rubber roller is pressed down, and contacts the traction steel roller, thereby driving the aramid paper to move.

[0015] Furthermore, the mesh number of the ceramic anilox roller is 50-100 meshes.

[0016] Furthermore, the unwinding and rewinding speeds of the equipment are set to 10-50 m / min; the temperature of the circulating air drying system is set to 100-200°C, and the air volume is set to 500-2000 m 3 / min.

[0017] In a second aspect, the present invention also provides a preparation method for improving the density and dielectric strength of aramid paper, wherein the aramid paper is formed by coating with aramid stock solution, and the coating equipment adopts the coating equipment described above.

[0018] Furthermore, the mesh number of the ceramic anilox roller is 90-100 mesh; at this time, the coating amount is less than 1.5 g / m 2 , the thickness of aramid paper remains unchanged, but the air permeability is reduced to 0.

[0019] Furthermore, the mesh number of the ceramic anilox roller is 60-70 meshes; at this time, the dielectric strength of the aramid paper is increased by more than 1 kV / mm, the water absorption is reduced to less than 1 / 3 of the original material, and the air permeability is reduced to 0.

[0020] Compared with the prior art, the above invention has the following advantages or beneficial effects:

[0021] (1) The coating equipment of the present invention adds a swing-arm tension roller, a circulating drying system, and a ceramic anilox roller, and adds an introduction and lead-out part to the three parts of the traditional coating machine. The pressure roller is used as a tension isolation to divide the tension structure into multiple sections, so that the stability, driving speed, and coating uniformity during operation are effectively improved. The tension is monitored in real time by the position of the swing arm of the swing-arm tension roller, and the tension stability is ensured by keeping the cylinder pressure consistent with the set tension, eliminating tension changes. The structure of the ceramic anilox roller combined with the liquid transfer roller can reduce the coating amount relatively stably by increasing the mesh count of the anilox roller and improve the coating uniformity; the circulating air drying system greatly shortens the drying time and increases the overall vehicle speed; by adding a swing-arm tension roller mechanism, the tension roller can be swung by pressure while detecting the tension, so that the tension is more stable.

[0022] (2) The present invention can effectively solve the problems of uneven coating, slow coating speed, unstable tension control, etc. when coating slurry on aramid paper. The method of the present invention can reduce the air permeability of the finished aramid paper and improve its dielectric strength. By solving the problem of excessive internal voids in the paper, the aramid paper can improve some physical indicators and be applied to a wider range of fields. At the same time, the quality of the finished paper can be improved for a second time, which reduces the loss in the daily production process and improves the product qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention and its features, appearance and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts in all the drawings. The drawings are not drawn completely to scale, and emphasis is placed on illustrating the subject matter of the present invention.

[0024] Figure 1 A front view of the overall structure of a coating device provided by one embodiment of the present invention;

[0025] Figure 2 A top view of the overall structure of a coating device provided by one embodiment of the present invention;

[0026] Figure 3 for Figure 1 An enlarged schematic diagram of the unwinding mechanism and the introduction mechanism;

[0027] Figure 4 for Figure 1 An enlarged schematic diagram of the middle coating system;

[0028] Figure 5 for Figure 1 An enlarged schematic diagram of the middle lead-out mechanism and the winding mechanism;

[0029] Among them, 1. unwinding mechanism; 2. coating system; 3. winding mechanism; 4. introduction mechanism; 5. extraction mechanism; 10. aramid paper; 1-11. first roll stand; 1-12. first inflatable shaft; 21. embossing roller; 22. embossing rubber roller; 23. ceramic anilox roller; 24. liquid transfer roller; 25. doctor blade; 26. circulating air drying system; 27. guide roller; 28. aramid stock solution pool; 29. ​​third arc roller; 3-11. second roll stand; 3-1 2. Second inflatable shaft; 41. First tension swing roller; 4-42. First tension sensor; 4-43. First swing roller cylinder; 44. First arc roller; 46. First pressure roller; 45. First top roller; 47. Second tension swing roller; 51. Third tension swing roller; 52. Second arc roller; 54. Second pressure roller; 53. Second top roller; 55. Fourth tension swing roller; 5-42. Second tension sensor; 5-43. Second swing roller cylinder. DETAILED DESCRIPTION

[0030] The structure of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but is not intended to limit the present invention.

[0031] In the description of the present invention, it should be noted that the terms "first", "second", "third", "fourth" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", "third", "fourth", etc. may explicitly or implicitly include one or more of the features.

[0032] In addition, the equipment structure and drawings of the present invention mainly describe the principle of the present invention. In terms of the technology of the design principle, the settings of the power mechanism, power supply system and control system of the device are not fully described. On the premise that the technical personnel in the field understand the principle of the above invention, the specific power mechanism, power supply system and control system can be clearly known. The control method of the application document is automatic control through a controller, and the control circuit of the controller can be realized by simple programming by the technical personnel in the field. The standard parts used can be purchased from the market, and can be customized according to the description and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt conventional models in the prior art, and the components known to the technical personnel in the field, their structures and principles are all known to the technical personnel in the field through technical manuals or conventional experimental methods.

[0033] Example 1

[0034] See also Figure 1 and 2 This embodiment provides a coating device for manufacturing aramid paper, including a unwinding mechanism 1, a coating system 2 and a rewinding mechanism 3; the aramid paper 10 without flatness treatment after hot pressing enters the coating device through the unwinding mechanism 1.

[0035] An introduction mechanism 4 is provided between the unwinding mechanism 1 and the coating system 2; a lead-out mechanism 5 is provided between the coating system 2 and the winding mechanism 3; the aramid paper 10 is introduced into the coating system 2 after passing through the first tension swing roller 41, the first arc roller 44, the first top roller 45, the first pressure roller 46, and the second tension swing roller 47 in the introduction mechanism 4 in sequence; the first pressure roller 46 is used as a tension isolation to divide the tension structure into multiple sections.

[0036] More specifically, the coating equipment is composed of an unwinding part, an introduction part, a coating part, a winding part, a PLC control system, a deviation correction control system, a pneumatic control system, a drying system, a cooling system, etc. The left and right wall panels of each part are connected by a crossbeam and a tie rod to form a frame; the parts are connected by a longitudinal beam to form a whole; the working mechanisms and control systems are respectively installed on the wall panels of each part or at the winding part, and form a mechatronic integrated coating unit with the main electrical control cabinet.

[0037] The structure and operation method of the unwinding mechanism 1 and the rewinding mechanism 3 are basically the same. Usually, the unwinding mechanism 1 includes a first reel 1-11 and a first air shaft 1-12 disposed at its center, a drive motor and a driver thereof. The rewinding mechanism 3 includes a second reel 3-11 and a second air shaft 3-12 disposed at its center, a drive motor and a driver thereof. For example, the drive motor can be selected as a 7.5KW+ENCODER+FAN type.

[0038] When the unwinding and rewinding mechanisms are linked, the closed-loop system tension, PLC automatic control, single-station unwinding and rewinding, and unwinding with EPC deviation correction device. The unwinding and rewinding motors are driven by synchronous belts. First, after the air shaft is deflated, it is inserted into the paper core of the new material roll and moved left and right to align the end face of the paper roll with the predetermined scale line on the air shaft. Then, the air gun equipped on the equipment is used to inflate the air shaft to about 0.4Mpa.

[0039] The introduction mechanism 4 is composed of a swing arm tension roller mechanism, a traction mechanism, an EPC deviation correction device, etc. The first top roller 45 and the first pressure roller 46 are double rollers with a rolling structure, which is a combination of steel and flexibility. The traction steel roller is driven by an independent motor and a synchronous arc toothed belt; the clutch of the traction rubber roller is pressed by a double cylinder, and the lifting is self-locking, and the pressure adjustment is completed by pneumatic components.

[0040] The first tension swing roller 41 and the second tension swing roller 47 form a swing arm tension roller group, which is combined with a steel flexible roller to ensure the division of tension sections. The first tension swing roller 41 can be provided with a matching first tension sensor 4-42 and a first swing roller cylinder 4-43 for tension control. Specifically, the swing roller is connected to the cylinder, and the tension sensor is connected to the cylinder; the swing roller can swing back and forth within a certain range, and apply force to the paper through the cylinder; the tension controller detects the force to ensure that the cylinder pressure is equal to the required tension; when the tension increases or decreases, since the cylinder pressure does not change, the swing roller will swing backward or forward to ensure stable tension. By keeping the cylinder pressure consistent with the set tension, the tension is stable and tension changes are eliminated.

[0041] More specifically, the potentiometer of the tension swing roller realizes synchronous tension detection, and the PLC controls the frequency converter to realize the synchronous tension closed loop. The soft roller is linked with the host and automatically controlled by the PLC. The low-damping tension swing roller can ensure stable printing tension, and the traction synchronous tension is accurately set by the precision pressure reducing valve.

[0042] When the swing arm tension roller mechanism is working, the tension is set by the imported precision pressure regulating valve, imported potentiometer or on the human-machine interface according to the needs of the process. If the tension of the film material passing through the swing roller is exactly equal to the pressure of the ultra-low friction cylinder, the swing arm is in a vertical position; if the tension changes, the swing arm leaves the vertical position and swings, and the displacement detector detects the position displacement of the swing arm, and the signal is fed back to the PLC control system. The PLC control system adjusts the speed or torque of the unwinding motor, the introduction motor, the lead-out motor, and the winding motor by adjusting the output of the unwinding inverter, the introduction inverter, the lead-out inverter, and the winding inverter, so that the material unwinding, feeding, and winding speeds are synchronized with the speed of the printing plate (ceramic anilox roller), thereby maintaining the required tension and realizing closed-loop tension control.

[0043] Limit seats are installed on both sides of the swing arm to limit the swing angle of the swing arm to prevent damage to the potentiometer.

[0044] The traction mechanism is mainly composed of a traction motor, a traction steel roller, a traction rubber roller, a cylinder, etc. The cylinder of the traction mechanism controls the rise and fall of the traction rubber roller by opening and closing. When working, the printing linkage / plate washing single-action conversion switch on the control cabinet panel is placed in the printing linkage position; when the start button is pressed, the main motor starts and the traction motor also starts, driving the traction steel roller to rotate through the coupling sleeve; when the traction roller pressing button is pressed, the cylinder piston rod moves downward, the traction rubber roller is pressed down, and contacts the traction steel roller, thereby driving the printing material. The pressure of the pressing surface is displayed on the traction pressure gauge, and the pressure value can be adjusted as needed through the knob below it. The traction motor can be selected as 5.5KW+ENCODER+FAN.

[0045] The coating system 2 includes an embossing roller 21, an embossing rubber roller 22, a ceramic anilox roller 23, a liquid transfer roller 24, a liquid doctor blade 25, and a circulating air drying system 26; the liquid transfer roller 24 transports the aramid stock solution from the aramid stock solution pool 28 to the ceramic anilox roller 23; the aramid paper 10 is coated through the gap between the ceramic anilox roller 23 and the embossing rubber roller 22, and then enters the circulating air drying system 26 for drying. Preferably, before the aramid paper 10 is coated, it is flattened, corrected, and tension adjusted by the third arc roller 29.

[0046] As a preferred technical solution, the ceramic anilox roller 23 is provided with a guide roller adjustment mechanism, and both sides thereof have a pointer-type horizontal adjustment mechanism for horizontal adjustment. The scraper 25 is preferably an adjustable structure with three degrees of freedom of lifting, front and back, and swing angle, reciprocating, with a stroke of 10mm, and is driven by a synchronous arc toothed belt and a gear box, and can be disconnected from the main transmission box. The connection between the gear box and the transmission shaft is a flexible connection. The downward pressing structure of the embossing roller 21 is a swing arm type, which cooperates with a guide roller to ensure that the material length change caused by the downward pressing / ascending is minimized. The embossing roller 21 adopts a swing arm type embossing mechanism, which can effectively compensate for the change in the length of the material belt. During operation, press the embossing roller 21 down button or the embossing roller 21 up button, the cylinder drives the swing arm to move, and the embossing roller applies pressure or releases pressure on the ceramic anilox roller, and its contact surface pressure value is displayed on the embossing roller pressure gauge on the control panel of the main control cabinet, and the pressure can be adjusted by the knob below it. Furthermore, each embossing cylinder of the whole machine is equipped with a rising self-locking device, and after the cylinder rises, the embossing rubber roller 22 will not fall due to lack of air source.

[0047] The guide rollers of the coating system are arranged reasonably to ensure the smooth running of the paper material; the ceramic anilox roller 23 is installed by pneumatic plate mounting, that is, by applying air pressure on both sides, which is convenient and fast and has good rigidity and strength.

[0048] The circulating air drying system is similar to the existing air drying system. It is composed of exhaust main pipeline, heating main pipeline using steam drying, drying fan, heat exchanger, metal hose, drying box and temperature automatic control system. The drying box is installed in the upper half of the printing group and is welded with steel plates. It is divided into fixed and movable parts. The joint surface of the two parts is machined and glued with sealing rubber to ensure the sealing when closed; the drying box is equipped with a blast chamber and an exhaust chamber, which are connected to the heat exchanger and the exhaust main pipeline through metal hoses. When working, turn on the dry fan button on the control panel of the main control cabinet to start the dry fan, and then turn on the heating button to turn on the heat source. Fresh air enters the heat exchanger under the action of the dry fan, enters the blast chamber through the jet port of the blast chamber after heating, and shoots to the film material to dry it, and then enters the exhaust chamber, and is discharged to the outdoors through the exhaust main pipeline under the action of the exhaust fan. The temperature in the drying box can be set on the temperature controller on the control panel of the main control cabinet according to the printing process requirements.

[0049] The aramid paper 10 is led out of the coating system 2 through the third tension swing roller 51, the second curved roller 52, the second top roller 53, the second pressure roller 54, and the fourth tension swing roller 55 in the lead-out mechanism 5 in sequence, and enters the winding mechanism 3. The mechanical structure and operation of the lead-out mechanism 5 are the same as those of the lead-in mechanism 4. The side of the fourth tension swing roller 55 can also be provided with a second tension sensor 5-42 and a second swing roller cylinder 5-43 for tension control.

[0050] According to the requirements of site layout, a plurality of guide rollers 27 are further provided between the introduction mechanism 4 or the withdrawal mechanism 5 and the coating system 2 .

[0051] Compared with the traditional coating machinery, the present invention newly adds a swing-arm tension roller, and the tension is monitored in real time by the position of the swing arm of the swing-arm tension roller, so as to ensure the stability of the tension and eliminate the tension change. The coating equipment adds the introduction and lead-out parts to the three parts of the traditional coating machinery, and the pressure roller is used as the tension isolation to divide the tension structure into multiple sections: unwinding introduction; introduction and coating; coating-drying-lead-out; lead-out and winding, so as to improve the stability of the tension. Compared with the metal anilox roller of the traditional coating device placed in the liquid tank, the rotation of the anilox roller and the scraping of the liquid into the liquid tank will generate foam, and the metal anilox roller has poor wettability to the coating material. By replacing it with a ceramic anilox roller with higher wettability, the coating uniformity is improved.

[0052] As an exemplary technical solution, the mesh number of the ceramic anilox roller 23 is 50-100 meshes. The unwinding and rewinding speeds of the equipment are set to 10-50 m / min; the temperature of the circulating air drying system is set to 100-200°C, and the air volume is set to 500-2000 m / min. 3 / min.

[0053] Example 2

[0054] This embodiment provides a preparation method for improving the density and dielectric strength of aramid paper, wherein aramid stock solution is used to coat the aramid paper, and the coating device is the coating device described in Example 1, and the method includes the following steps:

[0055] 1) Prepare raw materials: prepare 100 meters of untreated flat aramid paper after hot pressing; the examples are 1#~3# sample aramid paper, with a nominal weight of 40g and a thickness of 0.05mm. The finished paper requires good appearance and no abnormal physical indicators. Different samples have slight differences in physical parameters due to production batches.

[0056] 2) Paper loading: Place each sample on the unwinding rack through the air shaft and close the chuck.

[0057] 3) Paper feeding: Each paper sample is fed into the coating system through the unwinding rack and the introduction mechanism according to the paper feeding route, dried by the drying system, and then passed through the lead-out mechanism, and finally wound up in the winding mechanism.

[0058] The main engine speed setting of this embodiment is: 10~50 m / min. The expected temperature setting of the drying system is: 100~200℃. The expected air volume setting of the drying system is: 500~2000m 3 / min. The mesh number of the ceramic anilox roller is preset to 50~100 mesh.

[0059] We tested the coating amounts of different batches of samples after coating with a conventional wet machine and with ceramic anilox rollers of different mesh sizes in Example 1 (see Table 1).

[0060] Table 1 Coating amount of different batches of aramid paper samples after being coated by a conventional wet machine and by a ceramic anilox roller with different mesh sizes in Example 1

[0061]

[0062] By comparing the data in Table 1, it can be found that the conventional wet water machine is used to apply the aramid stock solution, and the coating is uneven, and it is difficult to ensure the consistency of the coating amount. The ceramic anilox roller plus the liquid transfer roller adopted in the present invention can increase the mesh number of the anilox roller and thus reduce the coating amount relatively stably. In addition, the circulating air drying system adopted in the present invention greatly shortens the drying time and increases the overall vehicle speed.

[0063] The physical properties of samples 1#, 2# and 3# after coating with conventional coating equipment were tested. The test results are shown in Table 2. The physical properties of samples 1#, 2# and 3# after coating with ceramic anilox rollers of different mesh sizes in Example 1 are shown in Table 3.

[0064] Table 2 Physical properties of samples 1#, 2# and 3# after coating using traditional coating equipment

[0065]

[0066] Table 3 Physical properties of samples 1#, 2# and 3# after coating with ceramic anilox rollers of different mesh sizes in Example 1

[0067]

[0068] From the data in Table 2 and Table 3, it can be found that for aramid paper of different types and thicknesses, the dielectric strength and air permeability of the paper coated with ceramic anilox roller are significantly improved compared with those before coating. The air permeability can be reduced to impermeable, the dielectric strength can be increased by more than 1 kV / mm, the water absorption is greatly reduced, and other parameters are not improved much. When the mesh number of the anilox roller is 90~100 mesh, the corresponding coating amount is less than 1.5g / m 2 , which has little effect on the thickness of the paper. This is because when the coating amount is small, the internal pores of the aramid paper are filled first, so the effect on the thickness is not great. When the mesh number of the ceramic anilox roller is 60-70 mesh, the dielectric strength of the aramid paper is increased by more than 1 kV / mm, the water absorption is reduced to less than 1 / 3 of the original material, and the air permeability is reduced to 0. However, the physical indicators of the paper coated with the traditional coating are improved slightly and are unstable. When the traditional coating machine is used to coat the aramid stock solution, the tension provided by the differential method at the two ends of the winding and unwinding is unstable due to the downward pressure of the pressure roller and the rotation of the anilox roller, which causes creases in the paper during the coating process. The device of the present invention can swing the tension roller by pressure while detecting the tension, so that the tension is more stable. Therefore, the physical properties of the paper coated with the aramid stock solution by the method of the present invention are improved at different coating amounts, among which the dielectric strength and air permeability are greatly improved.

[0069] In summary, the present invention provides a coating device for manufacturing aramid paper and a preparation method for improving the density and dielectric strength of aramid paper. Compared with the traditional coating machinery, the coating device adds a swing-arm tension roller, a circulating drying system, and a ceramic anilox roller, and adds an introduction and lead-out part to the three parts of the traditional coating machinery. The pressure roller is used as a tension isolation to divide the multi-section tension structure during the introduction and lead-out, so that the stability, driving speed, and coating uniformity in operation are effectively improved. The tension is monitored in real time by the position of the swing arm of the swing-arm tension roller, and the tension is kept stable by keeping the cylinder pressure consistent with the set tension, eliminating tension changes. The structure of the ceramic anilox roller combined with the liquid transfer roller can reduce the coating amount relatively stably by increasing the mesh count of the anilox roller, and improve the coating uniformity; the circulating air drying system greatly shortens the time required for drying and improves the overall vehicle speed; by adding a swing-arm tension roller mechanism, the tension roller can be swung by pressure while detecting the tension, so that the tension is more stable. The invention can solve the problems of poor surface flatness of aramid paper, excessive internal pores, high water absorption and air permeability.

[0070] Those skilled in the art should understand that those skilled in the art can implement variations by combining the prior art and the above embodiments, which will not be described in detail here. Such variations do not affect the essential content of the present invention, and will not be described in detail here.

[0071] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

Claims

1. A coating device for manufacturing aramid paper, comprising an unwinding mechanism (1), a coating system (2) and a winding mechanism (3); characterized in that: The aramid paper (10) that has not been processed for flatness after hot pressing enters the coating device through the unwinding mechanism (1); An introduction mechanism (4) is provided between the unwinding mechanism (1) and the coating system (2); an extraction mechanism (5) is provided between the coating system (2) and the winding mechanism (3); the aramid paper (10) is introduced into the coating system (2) after passing through the first tension swing roller (41), the first arc roller (44), the first top roller (45), the first pressure roller (46), and the second tension swing roller (47) in the introduction mechanism (4) in sequence; the first pressure roller (46) serves as a tension isolation to divide the tension structure into multiple sections; The coating system (2) comprises an embossing roller (21), an embossing rubber roller (22), a ceramic anilox roller (23), a liquid transfer roller (24), a liquid scraper (25), and a circulating air drying system (26); the liquid transfer roller (24) transports aramid stock solution from an aramid stock solution pool (28) to the ceramic anilox roller (23); the aramid paper (10) passes through a gap between the ceramic anilox roller (23) and the embossing rubber roller (22) for coating, and then enters the circulating air drying system (26) for drying; The aramid paper (10) is led out of the coating system (2) through the third tension swing roller (51), the second arc roller (52), the second top roller (53), the second pressure roller (54), and the fourth tension swing roller (55) in the lead-out mechanism (5) in sequence, and enters the winding mechanism (3).

2. The coating equipment for manufacturing aramid paper according to claim 1, characterized in that: Matching tension sensors and swing roller cylinders are respectively provided on the sides of the first tension swing roller (41) and the fourth tension swing roller (55) to control the tension.

3. The coating equipment for manufacturing aramid paper according to claim 1, characterized in that: The unwinding mechanism (1) and the rewinding mechanism (3) respectively comprise a reel and an air shaft arranged at the center thereof, a drive motor and a drive thereof.

4. The coating equipment for manufacturing aramid paper according to claim 1, characterized in that: The introduction mechanism (4) or the lead-out mechanism (5) further comprises a traction mechanism, and a plurality of guide rollers (27) are provided between the traction mechanism and the coating system (2); the embossing roller (21) adopts a swing-arm type embossing mechanism.

5. The coating equipment for manufacturing aramid paper according to claim 4, characterized in that: The traction mechanism includes a traction motor, a traction steel roller, a traction rubber roller, and a cylinder; when the main motor is started, the traction motor is started, and the traction steel roller is driven to rotate through the coupling sleeve; when coating is started, the cylinder piston rod moves downward, the traction rubber roller is pressed down, and contacts the traction steel roller, thereby driving the aramid paper to move.

6. The coating equipment for manufacturing aramid paper according to claim 1, characterized in that: The ceramic anilox roller (23) has an anilox mesh count of 50 to 100 meshes.

7. The coating equipment for manufacturing aramid paper according to claim 6, characterized in that: The unwinding and rewinding speeds of the equipment are set to 10-50 m / min; the temperature of the circulating air drying system is set to 100-200°C, and the air volume is set to 500-2000 m 3 / min.

8. A method for improving the density and dielectric strength of aramid paper, characterized in that: Aramid paper is formed by coating with aramid stock solution, and the coating equipment adopts the coating equipment as described in any one of claims 1 to 7.

9. A method for improving the density and dielectric strength of aramid paper according to claim 8, characterized in that: The mesh number of the ceramic anilox roller is 90~100 mesh; at this time, the coating amount is less than 1.5g / m 2 , the thickness of aramid paper remains unchanged, but the air permeability is reduced to 0.

10. The method for improving the density and dielectric strength of aramid paper according to claim 8, characterized in that: The mesh number of the ceramic anilox roller is 60~70 mesh; at this time, the dielectric strength of the aramid paper is increased by more than 1 kV / mm, the water absorption is reduced to less than 1 / 3 of the original material, and the air permeability is reduced to 0.

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