A PLA coated paper processing coating system

Abstract

The invention provides a PLA coated paper processing coating system, belonging to the coating paper processing technical field, the invention comprises a main machine platform, an unwinding platform, a winding platform and a coating seat, the unwinding platform is rotatably provided with an unwinding roller and a preheating roller for preheating paper, the main machine platform is rotatably provided with a main cooling roller and an auxiliary cooling roller, and also comprises: a corona cooling component, a scraper intercepting component, and an adaptive heating component; by controlling the synergistic effect of heating, cooling, the scraper intercepting component and the heating module, the cleanliness of the surface of the main cooling roller and the consistency of the compaction strength are maintained, thereby obtaining a uniform and stable coating effect and product quality; the design of the scraper seat is based on the temperature and fluidity difference of molten PLA, realizes the classification treatment of molten PLA, intercepts a part of molten PLA with lower temperature, prevents its backflow from affecting the temperature of molten PLA output by the coating seat, and at the same time, reflows and utilizes the molten PLA with higher temperature and good fluidity, thereby reducing the waste of raw materials.

Description

Technical Field

[0001] The invention relates to the technical field of laminated paper processing, and in particular to a PLA laminated paper processing laminating system. Background Art

[0002] PLA is a biodegradable material derived from renewable resources such as corn starch or sugar cane. Using PLA as a coating material not only reduces dependence on petroleum-based plastics, but also allows biodegradation through composting after use, reducing environmental pollution. PLA coated paper has good waterproof and oil-proof properties, which can effectively prevent moisture and grease from penetrating into the paper, keeping the paper products dry and clean. This feature makes PLA coated paper products very suitable for food packaging and catering services.

[0003] Most of the current PLA coated paper processing coating devices have some shortcomings in actual use. First, in actual use, part of the molten PLA will inevitably adhere to the surface of the cooling roller. This adhesion phenomenon will not only reduce the cooling efficiency of the cooling roller, because the adhered molten PLA will hinder the effective transfer of heat, but also may cause inconsistent compaction strength during the compaction process. Due to the uneven surface of the cooling roller, the coated paper may be subjected to uneven pressure when passing through, thereby affecting the overall quality and performance of the coated paper product, such as flatness, strength, etc.; second, even if some equipment can clean up the molten PLA adhered to the surface of the cooling roller in time, most of the current coating devices have not designed an effective recycling mechanism. Therefore, these cleaned hot-melt PLA are often treated as waste, resulting in a significant waste of raw materials, which not only increases production costs, but also creates an unnecessary burden on the environment.

[0004] How to invent a PLA coated paper processing coating system to solve these problems has become an urgent problem to be solved by technicians in this field. Summary of the invention

[0005] In order to make up for the above shortcomings, the present invention provides a PLA coated paper processing coating system, aiming to solve the problems mentioned in the above background.

[0006] The present invention is achieved in that:

[0007] The present invention provides a PLA coated paper processing coating system, comprising a main machine, an unwinding machine, a winding machine and a coating seat, wherein the unwinding machine is rotatably provided with an unwinding roller and a preheating roller for preheating paper, the winding machine is rotatably provided with a winding roller and a driving roller, the main machine is rotatably provided with a main cooling roller and an auxiliary cooling roller, and further comprising:

[0008] Corona cooling assembly: the corona cooling assembly is arranged on the main machine platform, and the corona cooling assembly is used to perform corona and cooling treatment on the paper;

[0009] Scraping and intercepting assembly: the scraping and intercepting assembly is arranged on one side of the laminating seat, and the scraping and intercepting assembly is used to scrape and store the raw materials adhered to the surface of the main cooling roller;

[0010] Adaptive heating component: The adaptive heating component is arranged inside the scraper and interception component, and the adaptive heating component is used to heat the raw materials scraped and stored by the scraper and interception component.

[0011] Preferably, the corona cooling assembly includes a high-voltage electrode, a grounding roller, a storage chamber, a cooling pipeline and a rotary joint. The storage chamber is arranged inside the main cooling roller, the auxiliary cooling roller and the grounding roller. The side wall of the cooling pipeline is connected with a flexible connecting pipe. The shafts of the main cooling roller, the auxiliary cooling roller and the grounding roller are all hollow. The ends of the shafts of the main cooling roller, the auxiliary cooling roller and the grounding roller are connected with the flexible connecting pipe through a rotary joint.

[0012] Preferably, the grounding roller is located directly below the high-voltage electrode. After the paper passes between the high-voltage electrode and the grounding roller, it passes through the auxiliary cooling roller, the laminating seat, the main cooling roller in sequence, bypasses several guide rollers, and is transferred to the driving roller, and finally rolled onto the winding roller.

[0013] Preferably, a plurality of guide ports are provided in a ring shape in the middle of the shaft of the main cooling roller, the auxiliary cooling roller and the grounding roller, a spoiler is fixedly installed on the side wall of the guide port, and the end of the cooling pipeline is connected to an external coolant delivery pump.

[0014] Preferably, the laminating seat is located between the main cooling roller and the auxiliary cooling roller, the upper end of the laminating seat is provided with a feed port, the lower end of the feed port is provided with a discharge port, and the hot melt PLA is coated on the preheated paper through the discharge port.

[0015] Preferably, the scraper intercepting assembly includes a scraper seat fixedly connected to the laminating seat, the scraper seat is arranged toward the side of the main cooling roller, the scraper seat is composed of an installation chamber and a scraper, the end of the scraper away from the laminating seat is abutted against the surface of the main cooling roller, and a sealed air cavity is arranged inside the installation chamber.

[0016] Preferably, a plurality of flow openings are equidistantly provided on the side wall of the scraper seat near the coating seat, a plurality of through grooves matching the flow openings are provided on the side wall of the coating seat corresponding to the flow openings, a slide groove is provided inside the scraper seat corresponding to the flow opening, a baffle is slidably arranged in the slide groove, an air guide passage is connected to the lower end of the slide groove, an end of the air guide passage passes through the side wall of the sealed air cavity, and the sealed air cavity is filled with an inert gas.

[0017] Preferably, a power storage module is installed at the bottom of the sealed air cavity, a plurality of connecting springs are fixedly connected to the top of the power storage module, a heating module is fixedly connected to the end of the connecting spring, the heating module is sealed and slidably connected to the sealed air cavity, and the baffle is sealed and slidably connected to the slide groove.

[0018] Preferably, the top of the heating module is below the scraper, the baffle is at the bottom of the chute in an initial state, and the height of the baffle is greater than the maximum length of the through-flow port.

[0019] Preferably, the adaptive heating component includes a second contact piece fixedly connected to the bottom of the heating module and a first contact piece fixedly connected to the top of the power storage module, the first contact piece and the power storage module, and the heating module and the second contact piece are electrically connected, the outside of the power storage module is covered with a heat-resistant shell, the first contact piece and the second contact piece are elastically arranged and are both on the inner side of the connecting spring.

[0020] The beneficial effects of the present invention are:

[0021] 1. The scraper in the scraper interception assembly can closely contact the surface of the main cooling roller, effectively scrape off the adhered molten PLA, and ensure the cleanliness of the main cooling roller surface and the consistency of the compaction strength; the scraper seat is used as a container for collecting and temporarily storing molten PLA, which prevents the molten PLA from flowing or splashing randomly and keeps the working environment clean; the design of the scraper seat is based on the temperature and fluidity differences of the molten PLA, and realizes the classification of the molten PLA, intercepting some of the molten PLA with lower temperature to prevent its reflux from affecting the temperature of the molten PLA output by the coating seat, and at the same time refluxes the molten PLA with higher temperature and good fluidity, reducing the waste of raw materials.

[0022] 2. Through the cooperation of the grounding roller and the high-voltage electrode, efficient corona treatment of the paper surface is achieved, which significantly increases the surface energy of the paper and improves its adsorption capacity for molten PLA. The grounding roller also serves as the first cooling line of defense, effectively preventing the paper from being deformed or damaged due to heat; the progressive gradient cooling design of the auxiliary cooling roller and the main cooling roller further compacts and cools the paper coated with molten PLA, reduces the thermal stress inside the paper, and ensures the high quality of the product.

[0023] 3. The heating module can automatically heat according to the accumulation of molten PLA inside the scraper seat, realizing adaptive heating of molten PLA and avoiding unnecessary energy waste. At the same time, the movement of the baffle and the opening degree of the flow port are controlled by the change of gas pressure, realizing automatic material transfer and uniform distribution of molten PLA, ensuring the effective utilization of materials in the coating seat; by controlling the synergistic effect of heating, cooling, scraper interception components and heating modules, the cleanliness of the surface of the main cooling roller and the consistency of the compaction strength are maintained, thereby obtaining a uniform and stable coating effect and product quality, and the molten PLA with higher temperature and good fluidity is refluxed, which significantly improves resource utilization and further reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the overall structure of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the cross-sectional structure of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0027] Figure 3 It is a front view schematic diagram of the cross-sectional structure of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of the structure of a main unit of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0029] Figure 5 It is a schematic diagram of the cross-sectional structure of a main unit of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0030] Figure 6 A PLA coated paper processing coating system provided by the embodiment of the present invention Figure 5 The enlarged structural diagram at A in the middle;

[0031] Figure 7 It is a front view schematic diagram of the cross-sectional structure of a main unit of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0032] Figure 8It is a schematic diagram of the installation position structure of a scraper seat of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0033] Fig. 9 It is a schematic diagram of a through slot structure of a PLA coated paper processing coating system provided by an embodiment of the present invention;

[0034] Fig.10 It is a schematic diagram of a scraper seat and a laminating cross-section structure of a PLA laminating paper processing laminating system provided by an embodiment of the present invention;

[0035] Fig.11 A PLA coated paper processing coating system provided by the embodiment of the present invention Fig.10 Enlarged structural diagram at B in the middle.

[0036] In the figure: 1. main machine; 2. unwinding table; 3. winding table; 4. cooling pipeline; 5. coating seat; 6. main cooling roller; 7. scraper seat; 8. high voltage electrode; 9. baffle; 21. unwinding roller; 22. preheating roller; 31. winding roller; 32. driving roller; 41. flexible connecting pipe; 51. feeding port; 52. discharging port; 53. through slot; 61. auxiliary cooling roller; 62. storage chamber; 63. guide port; 64. spoiler; 71. installation chamber; 72. scraper; 73. flow port; 74. power storage module; 75. heating module; 76. connecting spring; 81. grounding roller; 91. slide slot; 92. air guide passage; 93. sealed air cavity; 741. first contact piece; 751. second contact piece. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1, refer to Figure 1-Figure 6 A PLA coated paper processing coating system includes a main station 1, a reeling station 2, a reeling station 3 and a coating seat 5, the reeling station 2 is rotatably provided with a reeling roller 21 and a preheating roller 22 for preheating paper, the reeling station 3 is rotatably provided with a reeling roller 31 and a driving roller 32, the main station 1 is rotatably provided with a main cooling roller 6 and an auxiliary cooling roller 61, and further includes:

[0039] Corona cooling assembly: The corona cooling assembly is arranged on the mainframe 1, and is used for performing corona and cooling treatment on the paper;

[0040] Scraping and intercepting assembly: The scraping and intercepting assembly is arranged on one side of the laminating seat 5, and is used to scrape and store the raw materials adhered to the surface of the main cooling roller 6;

[0041] Adaptive heating component: The adaptive heating component is arranged inside the scraper and interception component, and the adaptive heating component is used to heat the raw materials scraped and stored by the scraper and interception component.

[0042] Furthermore, the corona cooling assembly includes a high-voltage electrode 8, a grounding roller 81, a storage chamber 62, a cooling pipeline 4 and a rotary joint. The storage chamber 62 is arranged inside the main cooling roller 6, the auxiliary cooling roller 61 and the grounding roller 81. The storage chamber 62 is used to contain coolant. The side wall of the cooling pipeline 4 is connected with a flexible connecting pipe 41. The shafts of the main cooling roller 6, the auxiliary cooling roller 61 and the grounding roller 81 are all hollow. The ends of the shafts of the main cooling roller 6, the auxiliary cooling roller 61 and the grounding roller 81 are connected with the flexible connecting pipe 41 through a rotary joint. Through the above arrangement, the circulation of the coolant can be ensured.

[0043] The grounding roller 81 is located directly below the high-voltage electrode 8. After the paper passes between the high-voltage electrode 8 and the grounding roller 81, it passes through the auxiliary cooling roller 61, the coating seat 5, the main cooling roller 6 in turn, and then bypasses several guide rollers and is transferred to the driving roller 32, and finally is rolled up on the winding roller 31. The high-voltage electrode 8 generates a high-voltage electric field, and the grounding roller 81, as the other end of the electric field, forms a potential difference with the high-voltage electrode 8. When the paper passes between the high-voltage electrode 8 and the grounding roller 81, due to the effect of the potential difference, corona discharge occurs on the surface of the paper. Corona discharge can change the polarity of the surface of the paper and form low-temperature plasma on the surface of the paper. These plasmas react with the molecules on the surface of the paper to generate polar groups (such as carbonyl and nitrogen-containing groups), thereby increasing the surface energy of the paper and improving its adsorption capacity for molten PLA, thereby enhancing the coating effect. Through corona treatment, the fiber structure on the surface of the paper is changed to a certain extent, becoming more open and easy to wet, which helps the molten PLA to better penetrate into the paper fibers and form a strong bonding layer.

[0044] The laminating seat 5 is located between the main cooling roller 6 and the auxiliary cooling roller 61 . A feed port 51 is provided at the upper end of the laminating seat 5 , and a discharge port 52 is provided at the lower end of the feed port 51 . The hot melt PLA is coated on the preheated paper through the discharge port 52 .

[0045] It should be noted that a plurality of guide ports 63 are provided in the middle of the shaft of the main cooling roller 6, the auxiliary cooling roller 61 and the grounding roller 81 in a ring shape, and a spoiler 64 is fixedly installed on the side wall of the guide port 63. The end of the cooling pipeline 4 is connected to an external coolant delivery pump, and the coolant delivery pump delivers the coolant from the outside to the cooling pipeline 4. The coolant enters the storage cavity 62 of the main cooling roller 6, the auxiliary cooling roller 61 and the grounding roller 81 through the flexible connecting pipe 41 and the guide port 63. In the storage cavity 62, the coolant passes through the guide port 63 and the spoiler 64. When the roller body rotates, the coolant inside the roller body can be moved to form turbulence inside the roller body. The turbulence can increase the contact area between the coolant and the inside of the roller body, thereby improving the cooling efficiency. At the same time, the turbulence also helps to take away the heat inside the roller body faster, ensuring that the surface of the roller body maintains a lower temperature, thereby improving the cooling efficiency.

[0046] In this embodiment, the paper is first placed on the unwinding roller 21. As the unwinding roller 21 rotates, the paper is gradually unwound. When the paper passes through the preheating roller 22, the preheating roller 22 preheats the paper so that the temperature of the paper reaches a temperature range suitable for lamination. Preheating helps the molten PLA to better combine with the paper.

[0047] After being guided by the guide roller, the preheated paper continues to move forward and enters between the high-voltage electrode 8 and the ground roller 81. The high-voltage electrode 8 generates a high-voltage electric field, and the ground roller 81, as the other end of the electric field, forms a potential difference with the high-voltage electrode 8. When the paper passes between the high-voltage electrode 8 and the ground roller 81, due to the effect of the potential difference, corona discharge occurs on the surface of the paper. The corona discharge can change the polarity of the surface of the paper and form low-temperature plasma on the surface of the paper. These plasmas react with the molecules on the surface of the paper to generate polar groups (such as carbonyl and nitrogen-containing groups), thereby increasing the surface energy of the paper and improving its adsorption capacity for molten PLA.

[0048] It should be noted that in the application, the grounding roller 81 is not only one of the key components of the corona treatment, but also serves as the first cooling line of defense. The surface of the grounding roller 81 comes into contact with the paper when it passes through, and the coolant takes away part of the heat from the paper through heat conduction, preventing it from being deformed or damaged due to heat, and ensuring the smooth progress of the subsequent coating and cooling processes.

[0049] The corona-treated paper continues to move forward and enters the coating seat 5. The upper end of the coating seat 5 is provided with a feed port 51. The hot-melt PLA enters the coating seat 5 through the feed port 51 and is coated on the preheated paper from the discharge port 52. The molten PLA forms a uniform thin film on the surface of the paper. The paper coated with PLA continues to move forward and passes through the auxiliary cooling roller 61 and the main cooling roller 6. The paper coated with molten PLA can be compacted and cooled by the extrusion and cooling effect of the auxiliary cooling roller 61 and the main cooling roller 6, so that the molten PLA can be better combined with the paper. Because the volume of the main cooling roller 6 is larger than that of the auxiliary cooling roller 61, its cooling effect is more significant. When the paper passes through the auxiliary cooling roller 61 and the main cooling roller 6 successively, it will undergo a gradual gradient cooling process. This gradual cooling helps to reduce the thermal stress inside the paper and prevent it from being deformed or damaged due to sudden temperature changes.

[0050] When the main cooling roller 6 rotates, the guide port 63 and the spoiler 64 cause the coolant to form turbulence inside the roller body. The turbulence can increase the contact area between the coolant and the inside of the roller body, thereby improving the cooling efficiency. At the same time, the turbulence also helps to take away the heat inside the roller body more quickly, ensuring that the surface temperature of the roller body remains low. In this way, when the paper contacts the main cooling roller 6, the molten PLA on the paper can be quickly cooled and solidified.

[0051] The cooled paper continues to move forward, passes around several guide rollers and is then transferred to the drive roller 32. The drive roller 32 provides power to move the paper forward and finally roll it up onto the winding roller 31. The rolled coated paper can be subsequently cut, packaged, and processed.

[0052] In this embodiment, the corona treatment of the paper surface is achieved through the cooperation of the grounding roller 81 and the high-voltage electrode 8, thereby increasing the surface energy of the paper and improving its adsorption capacity for molten PLA. The grounding roller 81 is not only a key component of the corona treatment, but also serves as the first cooling line of defense, effectively preventing the paper from being deformed or damaged due to heat; the extrusion and cooling effects of the auxiliary cooling roller 61 and the main cooling roller 6 further compact and cool the paper coated with molten PLA, so that PLA and the paper are better combined. The volume of the main cooling roller 6 is larger than that of the auxiliary cooling roller 61, and progressive gradient cooling is achieved, which helps to reduce the thermal stress inside the paper and prevent deformation or damage. The guide port 63 and the spoiler 64 inside the roller body (grounding roller 81, auxiliary cooling roller 61 and main cooling roller 6) are designed to form turbulence in the coolant, increase the contact area between the coolant and the inside of the roller body, and improve the cooling efficiency. The turbulence also helps to take away the heat inside the roller body faster, ensuring that the surface of the roller body maintains a low temperature, thereby accelerating the cooling and solidification of the molten PLA on the paper. The combined effect of these two processes ensures the high-quality production of PLA coated paper.

[0053] Example 2, refer to Figure 5-Figure 11 The scraper interception assembly includes a scraper seat 7 fixedly connected to the laminating seat 5, and the scraper seat 7 is arranged toward the side of the main cooling roller 6. The scraper seat 7 is composed of a mounting chamber 71 and a scraper 72. The end of the scraper 72 away from the laminating seat 5 is against the surface of the main cooling roller 6. When the main cooling roller 6 rotates, the molten PLA adhered to the surface of the main cooling roller 6 can be effectively scraped off and accommodated in the scraper seat 7 to ensure the cleanliness of the surface of the main cooling roller 6, thereby ensuring consistent compaction strength. A sealed air cavity 93 is arranged inside the mounting chamber 71.

[0054] It should be noted that the molten PLA scraped off by the scraper 72 is divided into two parts, one part is the molten PLA in the lower part (close to the main cooling roller 6), and the other part is the molten PLA in the upper part. The molten PLA in the lower part is in direct contact with the main cooling roller 6, so its solid temperature is lower (lower fluidity), while the molten PLA in the upper part has a higher temperature (higher fluidity). The molten PLA in the solid upper part can be directly refluxed for reuse, while the molten PLA in the lower part is intercepted and stored in the scraper seat 7, which can ensure that the temperature of the molten PLA output by the coating seat 5 is relatively constant.

[0055] Furthermore, a plurality of flow openings 73 are equidistantly provided on the side wall of the scraper seat 7 near the coating seat 5, a plurality of through grooves 53 matching the flow openings 73 are provided on the side wall of the coating seat 5 corresponding to the flow openings 73, a slide groove 91 is provided inside the scraper seat 7 corresponding to the flow openings 73, a baffle 9 is slidably provided inside the slide groove 91, an air guide passage 92 is connected to the lower end of the slide groove 91, an end of the air guide passage 92 passes through the side wall of the sealed air cavity 93, and the sealed air cavity 93 is filled with an inert gas, such as helium, neon, etc., which has extremely high thermal stability and chemical inertness, and is not easy to react at high temperatures, so its physical and chemical properties do not change much during the heating process.

[0056] A power storage module 74 is installed at the bottom of the sealed air cavity 93, and a plurality of connecting springs 76 are fixedly connected to the top of the power storage module 74. A heating module 75 is fixedly connected to the end of the connecting spring 76. The heating module 75 is sealed and slidably connected to the sealed air cavity 93, and the baffle 9 is sealed and slidably connected to the slide groove 91 to prevent gas leakage.

[0057] It should be noted that the top of the heating module 75 is below the scraper 72 to ensure that the molten PLA entering the scraper seat 7 will slide down to the top of the heating module 75. In the initial state, the baffle 9 is at the bottom of the chute 91 (refer to Fig.11), at this time, the flow port 73 is in an open state. When the molten PLA slides over the heating module 75, pressure is applied to the connecting spring 76 to compress it, indicating that the heating module 75 is in a downward state at this time. The heating module 75 will compress the gas inside the sealed air cavity 93, and a part of the gas will enter the chute 91 through the air guide passage 92. As the heating module 75 continues to move downward, the gas thrust will gradually become greater than the gravity of the baffle 9, and will eventually gradually lift up the baffle 9. The height of the baffle 9 is greater than the maximum length of the flow port 73, ensuring that the baffle 9 can completely block the flow port 73 after being lifted up.

[0058] In this embodiment, when the main cooling roller 6 is rotating, a certain amount of molten PLA may adhere to its surface. If this adhesion phenomenon is not handled in time, it will not only affect the cooling effect of the main cooling roller 6, but may also cause inconsistent compaction strength, thereby affecting the quality and performance of the final product.

[0059] In order to solve this problem, the scraper 72 in the scraper interception assembly plays a key role. The scraper 72 is designed to be in close contact with the surface of the main cooling roller 6. When the main cooling roller 6 rotates, the scraper 72 can use its sharp edge or appropriate scraping force to effectively scrape off the molten PLA adhered to the surface of the main cooling roller 6. The scraped molten PLA is then received into the scraper seat 7. The scraper seat 7 serves as a container for collecting and temporarily storing molten PLA. Its design can ensure that the molten PLA will not flow or splash out at will, thereby keeping the working environment clean and orderly.

[0060] By continuously scraping and collecting the molten PLA, the scraper interception assembly can ensure the cleanliness of the surface of the main cooling roller 6, which is crucial to maintaining the consistency of the compaction strength, because only when the surface of the main cooling roller 6 is clean and free of adhesion can it compact the molten PLA at a constant pressure and speed, thereby producing products with stable quality.

[0061] In the laminating process, when the molten PLA is coated onto the preheated paper and passes through the main cooling roller 6, part of the molten PLA will adhere to the surface of the main cooling roller 6. Due to the direct contact with the roller surface, the adhered molten PLA will be rapidly cooled to form a lower part of the molten PLA with a lower temperature and lower fluidity. At the same time, the molten PLA in the upper part has less contact with the roller surface and is affected by the surrounding thermal environment, so its temperature is relatively high and its fluidity is stronger.

[0062] The design of the scraper 72 is based on the temperature and fluidity differences of the molten PLA. When the main cooling roller 6 rotates, the scraper 72 will scrape off the molten PLA on the roller surface. In this process, the lower part of the molten PLA has a low temperature and poor fluidity, so it is more likely to be retained by the scraper 72 inside the scraper seat 7. The upper part of the molten PLA has a high temperature and good fluidity, so it will flow directly back to the coating seat 5 under the guidance of the flow port 73 and the through groove 53 during the scraping process for reuse.

[0063] The advantage of this classification processing mechanism is that by intercepting some of the molten PLA with a lower temperature, it can be prevented from flowing back into the coating seat 5, thereby avoiding adverse effects on the temperature of the molten PLA output by the coating seat 5. In this way, the temperature of the molten PLA output by the coating seat 5 can be kept relatively constant, which is conducive to obtaining a uniform coating effect and stable product quality; and the molten PLA with a higher temperature and good fluidity in the upper part is directly refluxed for utilization, which can reduce the waste of raw materials and improve resource utilization. At the same time, this also reduces production costs and energy consumption.

[0064] During the continuous coating process, molten PLA with a lower temperature will gradually accumulate inside the scraper seat 7. This part of the molten PLA will exert downward pressure on the top of the heating module 75 due to its contact with the top of the heating module 75. As the accumulation amount increases, this pressure will gradually increase. Since this part of the molten PLA is above the heating module 75, when the pressure exerted by the molten PLA increases to a certain extent, it will compress the connecting spring 76, causing the heating module 75 to move downward as a whole. This downward movement process not only changes the contact state between the heating module 75 and the molten PLA, but also affects the gas pressure inside the sealed air cavity 93.

[0065] The sealed air cavity 93 is a relatively closed space filled with a certain amount of gas. When the heating module 75 moves downward, it compresses the gas inside the sealed air cavity 93, causing the gas pressure to increase. The increased gas pressure will seek a way to release, and the gas guide passage 92 is such a way. The gas guide passage 92 connects the sealed air cavity 93 with the slide groove 91. When the gas pressure increases, a part of the gas will enter the slide groove 91 through the gas guide passage 92, generating a thrust on the baffle 9. This thrust increases with the increase of the gas pressure, and will eventually be greater than the gravity of the baffle 9.

[0066] Under the action of gas thrust, the baffle 9 will be gradually lifted up until the flow port 73 is completely blocked. Since the height of the baffle 9 is greater than the maximum length of the flow port 73, when the baffle 9 is fully lifted up, it can ensure that the flow port 73 is completely blocked, thereby preventing the molten PLA accumulated inside the scraper seat 7 from being accidentally squeezed into the laminating seat 5 due to gravity. This self-protection mechanism not only ensures the stable operation of the scraper interception assembly, but also avoids production accidents and quality problems caused by accidental leakage of molten PLA.

[0067] The scraper interception component effectively solves the problem of molten PLA adhering to the surface of the main cooling roller 6 through its ingenious scraping and containing mechanism, ensuring the consistency of the compaction strength and the quality of the final product; the molten PLA on the main cooling roller 6 is scraped off by the scraper 72, and the synergistic effect of the heating module 75 and the sealed air cavity 93 is utilized to achieve the classification and effective utilization of the molten PLA. At the same time, the automatic blocking function of the baffle 9 prevents the molten PLA accumulated inside the scraper seat 7 from being accidentally squeezed into the coating seat 5 due to the action of gravity. This design not only improves the production efficiency, but also ensures that the temperature of the molten PLA output by the coating seat 5 is relatively constant, thereby improving the product quality.

[0068] Example 3, refer to Figure 8-Figure 11 The adaptive heating component includes a second contact piece 751 fixedly connected to the bottom of the heating module 75 and a first contact piece 741 fixedly connected to the top of the power storage module 74. The first contact piece 741 and the power storage module 74, and the heating module 75 and the second contact piece 751 are electrically connected. When the heating module 75 moves downward, the second contact piece 751 will eventually contact the first contact piece 741. At this time, the power storage module 74 will supply power to the heating module 75, and the heating module 75 will start to heat the molten PLA (with a lower temperature) inside the scraper seat 7 to make it meet the coating standards.

[0069] It should be noted that the outside of the power storage module 74 is covered with a heat-resistant shell to protect it from the impact of high temperature environment and ensure its stable operation under harsh working conditions. The first contact piece 741 and the second contact piece 751 are both elastically set and are both on the inner side of the connecting spring 76, which helps to adapt to the compression and release process of the connecting spring 76 and ensure that the electrical connection will not be interrupted when the heating module 75 moves up and down.

[0070] In this embodiment, when the molten PLA accumulated inside the scraper seat 7 increases and applies pressure to the heating module 75, the heating module 75 will compress the connecting spring 76 and move downward. As the heating module 75 moves downward, the second contact piece 751 will approach the first contact piece 741, but due to the elastic setting of the contact piece, they can maintain good electrical contact. The power storage module 74 supplies power to the heating module 75 through the first contact piece 741 and the second contact piece 751, so that it generates heat to adjust the temperature of the molten PLA to meet the coating standards.

[0071] As the heating progresses, the fluidity of the molten PLA accumulated inside the scraper seat 7 will increase, and it will flow into the coating seat 5 through the gap between the top of the baffle 9 and the flow port 73, which will cause the pressure on the connecting spring 76 to drop, and the connecting spring 76 begins to rebound. At this time, the heating module 75 begins to move up and gradually moves to its original position, and the volume of the sealed air cavity 93 changes accordingly. Since the sealed air cavity 93 is connected to the slide groove 91 through the air guide passage 92, this affects the gas pressure in the slide groove 91. Due to the change in gas pressure, this will cause the baffle 9 to move down. At this time, the flow port 73 is in a partially open state, and the molten PLA that has been heated will flow back to the inside of the coating seat 5 through the flow port 73, waiting for a new round of heating cycle.

[0072] This mechanism cleverly combines the principles of physics and thermodynamics to achieve adaptive heating of molten PLA and automatic material transfer. It can not only control the heating of molten PLA according to the accumulation of molten PLA, avoiding unnecessary waste of energy, but also control the movement of the baffle 9 and the opening degree of the flow port 73 by changes in gas pressure, ensuring uniform distribution of the material in the laminating seat 5.

[0073] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A PLA coated paper processing coating system, comprising a main station (1), an unwinding station (2), a winding station (3) and a coating seat (5), wherein the unwinding station (2) is rotatably provided with an unwinding roller (21) and a preheating roller (22) for preheating paper, the winding station (3) is rotatably provided with a winding roller (31) and a driving roller (32), and the main station (1) is rotatably provided with a main cooling roller (6) and an auxiliary cooling roller (61), characterized in that: Also includes: Corona cooling component: the corona cooling component is arranged on the main platform (1), and is used to perform corona and cooling treatment on paper; The corona cooling assembly comprises a high-voltage electrode (8), a grounding roller (81), a storage chamber (62), a cooling pipeline (4) and a rotary joint; A scraper and interception assembly: the scraper and interception assembly is arranged on one side of the laminating seat (5), and is used to scrape and store the raw materials adhered to the surface of the main cooling roller (6); The scraper interception assembly comprises a scraper seat (7) fixedly connected to the laminating seat (5), the scraper seat (7) comprising a mounting chamber (71) and a scraper plate (72), and a sealed air cavity (93) is provided inside the mounting chamber (71); A plurality of flow openings (73) are equidistantly provided on the side wall of the scraper seat (7) near the laminating seat (5); a slide groove (91) is provided inside the scraper seat (7) corresponding to the flow openings (73); a baffle (9) is slidably provided inside the slide groove (91); and an air guide passage (92) is provided at the lower end of the slide groove (91); A power storage module (74) is installed at the bottom of the sealed air cavity (93); a plurality of connection springs (76) are fixedly connected to the top of the power storage module (74); and a heating module (75) is fixedly connected to the end of the connection spring (76); Adaptive heating component: the adaptive heating component is arranged inside the scraper interception component, and the adaptive heating component is used to heat the raw materials scraped by the scraper interception component; The adaptive heating component comprises a second contact piece (751) fixedly connected to the bottom of the heating module (75) and a first contact piece (741) fixedly connected to the top of the power storage module (74).

2. A PLA coated paper processing coating system according to claim 1, characterized in that: The storage chamber (62) is arranged inside the main cooling roller (6), the auxiliary cooling roller (61) and the grounding roller (81); the side wall of the cooling pipeline (4) is connected to a flexible connecting pipe (41); the shafts of the main cooling roller (6), the auxiliary cooling roller (61) and the grounding roller (81) are all hollow; and the ends of the shafts of the main cooling roller (6), the auxiliary cooling roller (61) and the grounding roller (81) are connected to the flexible connecting pipe (41) via a rotating joint.

3. A PLA coated paper processing coating system according to claim 2, characterized in that: The grounding roller (81) is located directly below the high-voltage electrode (8). After passing between the high-voltage electrode (8) and the grounding roller (81), the paper passes through the auxiliary cooling roller (61), the laminating seat (5), the main cooling roller (6) in sequence, bypasses a number of guide rollers, and is transferred to the driving roller (32), and is finally rolled up onto the winding roller (31).

4. A PLA coated paper processing coating system according to claim 2, characterized in that: A plurality of guide ports (63) are provided in the middle of the shafts of the main cooling roller (6), the auxiliary cooling roller (61) and the grounding roller (81) in a ring shape, and a spoiler (64) is fixedly mounted on the side wall of the guide port (63). The end of the cooling pipeline (4) is connected to an external coolant delivery pump.

5. A PLA coated paper processing coating system according to claim 1, characterized in that: The laminating seat (5) is located between the main cooling roller (6) and the auxiliary cooling roller (61), and a feed port (51) is provided at the upper end of the laminating seat (5), and a discharge port (52) is provided at the lower end of the feed port (51), and hot-melt PLA is coated on the preheated paper through the discharge port (52).

6. A PLA coated paper processing coating system according to claim 1, characterized in that: The scraper seat (7) is arranged toward one side of the main cooling roller (6), and the end of the scraper (72) away from the laminating seat (5) abuts against the surface of the main cooling roller (6).

7. A PLA coated paper processing coating system according to claim 6, characterized in that: The side wall of the coating seat (5) corresponding to the flow opening (73) is provided with a plurality of through grooves (53) matching the flow opening (73), and the end of the air guide passage (92) passes through the side wall of the sealed air cavity (93), and the sealed air cavity (93) is filled with an inert gas.

8. A PLA coated paper processing coating system according to claim 7, characterized in that: The heating module (75) is in sealed sliding connection with the sealed air cavity (93), and the baffle (9) is in sealed sliding connection with the slide groove (91).

9. A PLA coated paper processing coating system according to claim 8, characterized in that: The top of the heating module (75) is located below the scraper (72), and in an initial state, the baffle (9) is located at the bottom of the slide groove (91), and the height of the baffle (9) is greater than the maximum length of the flow opening (73).

10. A PLA coated paper processing coating system according to claim 8, characterized in that: The first contact piece (741) and the power storage module (74), as well as the heating module (75) and the second contact piece (751) are all electrically connected; the outside of the power storage module (74) is covered with a heat-resistant shell; the first contact piece (741) and the second contact piece (751) are both elastically arranged and are located on the inner side of the connection spring (76).

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