Production method of flame-retardant plastic film

Abstract

The invention discloses a production method of a flame-retardant plastic film. The production method comprises the following steps: S1, preparing raw materials; s2, extrusion molding; s3, biaxial stretching; s4, corona treatment; s5, trimming and cutting; and S6, packaging. Through cooperative use of the shell, the cutter A, the cutter B and the displacement mechanism, the edge cutting function and the slitting function can be integrated, a flame-retardant plastic film does not need to be repeatedly transferred between the two devices, the time for middle shutdown and repositioning is saved, and the production continuity is remarkably improved; edge cutting and slitting are conducted synchronously, the machining period is further shortened, and the requirement for large-batch production is met; the cutting machine occupies less space and is suitable for factories with limited space; meanwhile, an operator only needs to monitor one device, so that the labor cost and the training complexity are reduced; and through cooperative use of the shell, the shell cover and the lifting mechanism, the cutter A and the cutter B can be hidden and stored, the situation that a worker touches the cutter A and the cutter B by mistake during operation can be avoided, and then the use safety of the equipment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic films, and more specifically, to a production method of a flame-retardant plastic film. Background Art

[0002] Plastic films are made of polyvinyl chloride, polyethylene, polypropylene, polystyrene, and other resins, and are used for packaging and as a coating layer. The share of plastic packaging and plastic packaging products in the market is increasing, especially composite plastic flexible packaging, which has been widely used in the fields of food, medicine, chemical industry, etc. Among them, food packaging accounts for the largest proportion, such as beverage packaging, frozen food packaging, cooked food packaging, fast food packaging, etc. These products have brought great convenience to people's lives.

[0003] The patent document with the publication number CN106554544B discloses a polyethylene composition and a flame-retardant film. When the polyethylene composition obtained by using components A, B, and C with specific melt indices and densities and a flame retardant in combination is used to prepare a polyethylene film by the flat film stretching method, it has the advantages of large stretching ratio and high film-forming rate, can meet the higher requirements of the flat film stretching method for polyethylene raw materials, and the polyethylene film prepared therefrom also has excellent flame retardant properties and great industrial application prospects.

[0004] Although the above-mentioned polyethylene composition and flame-retardant film can solve the corresponding technical problems, during the production process, the flame-retardant film needs to be trimmed by a trimming machine first, and after trimming, it is then slit by a slitter according to customer requirements and production specifications. Therefore, the film needs to be repeatedly transferred between two devices, increasing the intermediate downtime and repositioning time, thereby reducing the production efficiency and making it difficult to meet the requirements of large-scale production.

[0005] Therefore, a production method of a flame-retardant plastic film is proposed. Summary of the Invention

[0006] The technical task of the present invention is to provide a production method of a flame-retardant plastic film to solve the above-mentioned problems.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A production method of a flame-retardant plastic film includes the following steps:

[0009] S1. Raw material preparation: Linear low-density polyethylene, a flame retardant, a catalyst, a coupling agent, and other additives are transported to a homogenizing bin according to a certain ratio for stirring and mixing, and then sent into a melt granulation system for extrusion granulation to obtain a polyethylene composition;

[0010] S2. Extrusion molding: Feed the polyethylene composition in step S1 into a casting machine through a conveyor belt or a feeder to form a melt. The melting and plasticizing temperature is 170 - 200 °C. Allow the melt to be extruded through a forming die in a sheet shape and cast onto the roller surface of a steadily rotating cooling roller to form a film sheet. Then, the film sheet is cooled and shaped on the cooling roller.

[0011] S3. Biaxial stretching: Heat the film sheet formed in step S2 on a heating roller. The heating temperature is 105 - 125 °C. After heat preservation for 15 - 30 min, feed it into a biaxial stretching device for the film to be stretched and formed. The stretched film sheet is cooled and shaped again through a cooling roller, and then the flame-retardant plastic film can be obtained.

[0012] S4. Corona treatment: Conduct corona treatment on the flame-retardant plastic film in step S3. The electrode voltage of the corona treatment is 7.0 - 8.5 kV, and the intensity of the corona treatment is 40 - 45 dym / cm.

[0013] S5. Trimming and cutting: Cut and trim the corona-treated flame-retardant plastic film in step S4 through a cutting machine. The cutting machine cuts the flame-retardant plastic film into the required length and width according to customer requirements and production specifications.

[0014] S6. Packaging: Wind the cut flame-retardant plastic film in step S5 into a roll through a winding machine for easy storage and transportation. Package the wound flame-retardant plastic film through a packaging machine to protect it from the external environment. Finally, mark the packaged flame-retardant plastic film with information including product name, specification, and batch number.

[0015] Preferably, the other additives in step S1 include but are not limited to at least one of antioxidant, slip agent, and anti-sticking agent.

[0016] Preferably, the cutting machine in step S5 includes a support plate A, a support plate B, a guiding mechanism, a housing, a cutter A, a cutter B, a displacement mechanism, and a lifting mechanism.

[0017] Among them, the support plate A and the support plate B have the same structural dimensions and are arranged parallel to each other. The guide mechanism is movably arranged between the support plate A and the support plate B for conveying and guiding the flame-retardant plastic film after corona. The shell is fixedly connected between the support plate A and the support plate B. The side of the shell facing the conveying direction of the flame-retardant plastic film is open. The surface of the shell is slidably connected with a shell cover that can cover the open part of the shell. The tool A and the tool B are respectively arranged in the inner cavity of the shell from top to bottom. The tool A is used to cut the flame-retardant plastic film into a desired width, and the tool B is used to cut the flame-retardant plastic film into a desired length. The displacement mechanism is arranged on the shell to drive the tool A and the tool B to enter or extend out of the inner cavity of the shell. The lifting mechanism is arranged on the shell to drive the shell cover to perform lifting operations.

[0018] Preferably, the guide mechanism comprises a plurality of guide rollers rotatably connected between the support plate A and the support plate B, an adjusting roller is movably connected between the support plate A and the support plate B, and a winding roller A and a winding roller B are rotatably connected between the support plate A and the support plate B, the winding roller A is located directly below the adjusting roller, and the winding roller B is located obliquely below the adjusting roller, a motor B is installed on the side of the support plate B away from the support plate A, the output shaft of the motor B is fixedly connected to the winding roller A, the winding roller A and the winding roller B are transmission-connected, and both ends of the adjusting roller are rotatably connected to an I-shaped block, the support plate A and the support plate B are respectively provided with through grooves A adapted to the I-shaped blocks, the I-shaped blocks and the through grooves A are arranged in a one-to-one correspondence, and the I-shaped blocks are slidably connected to the inner wall surface of the corresponding through groove A, and the inner cavity of the through groove A is installed with an electric telescopic rod B, and the output end of the electric telescopic rod B is fixedly connected to the corresponding I-shaped block.

[0019] Preferably, the tool A includes a bracket arranged in the inner cavity of the shell, the inner cavity of the bracket is rotatably connected to a bidirectional screw, the outer surface of the bracket is installed with a motor A, the output shaft of the motor A passes through the inner cavity of the bracket and is fixedly connected to one end of the bidirectional screw, the surface movable sleeve of the bidirectional screw is provided with a plurality of equally distributed movable sleeves, wherein the inner wall surfaces of the two outermost movable sleeves are both threadedly connected to the bidirectional screw, and the inner wall surfaces of the remaining movable sleeves are slidably connected to the bidirectional screw, and the plurality of movable sleeves are connected by a scissor-type linkage mechanism, and a blade A is provided on the side of the movable sleeve facing the adjusting roller, and a connecting piece is provided between the blade A and the corresponding movable sleeve.

[0020] Preferably, the connecting member includes a fixing bracket fixedly connected to one side of the movable sleeve. One side of the movable sleeve is also rotatably connected to a movable bracket. One end of the fixing bracket and the movable bracket penetrates to the outside of the housing. The blade A is arranged between the fixing bracket and the movable bracket. A locking member is arranged between the fixing bracket and the movable bracket. A clamping protrusion is fixedly connected to both sides of the blade A. A clamping groove is respectively formed on one side of the fixing bracket and the movable bracket that are symmetric to each other. The clamping protrusions and the clamping grooves are arranged in one-to-one correspondence. The clamping protrusions are clamped into the inner cavity of the clamping grooves;

[0021] Among them, the locking member includes a screw rod fixedly connected to one side of the fixing bracket. A groove for the screw rod to pass through is formed on the surface of the movable bracket. A nut sleeve is threadedly sleeved on one end of the screw rod surface. One side of the nut sleeve is in contact with the surface of the movable bracket.

[0022] Preferably, the tool B includes a mounting plate movably connected to the inner cavity of the housing and located below the bracket. A tool body is arranged on one side of the mounting plate facing the adjusting roller. Both ends of the mounting plate and the tool body are in contact with the inner wall surface of the housing;

[0023] Among them, the tool body includes a connecting plate arranged on one side of the mounting plate. A blade B is fixedly connected to one side of the connecting plate away from the mounting plate. A limiting strip is integrally formed on one side of the mounting plate. A limiting groove adapted to the limiting strip is formed on one side of the connecting plate. The inner wall surface of the limiting groove is slidably connected to the surface of the limiting strip.

[0024] Preferably, the displacement mechanism includes an electric telescopic rod A installed on the outside of the housing. The output end of the electric telescopic rod A penetrates to the inner cavity of the housing and is fixedly connected to a push plate. The push plate is slidably connected to the inner wall surface of the housing. Two groups of guiding members arranged up and down are provided on the push plate. One group of the guiding members is correspondingly arranged with the bracket, and the other group of the guiding members is correspondingly arranged with the mounting plate;

[0025] Among them, the guiding member includes a guide rod movably penetrating through the push plate. One end of the guide rod extends to the outside of the housing. The other end of one group of the guide rods is fixedly connected to the surface of the bracket. The other end of the other group of the guide rods is fixedly connected to one side of the mounting plate. A spring is sleeved on the surface of the guide rod. The two ends of the spring located above are respectively fixedly connected to the push plate and the bracket. The two ends of the spring located below are respectively fixedly connected to the push plate and the mounting plate.

[0026] Preferably, the cutting edge of the blade B is located below the fixing bracket. The extending length of the guide rod located below is greater than the extending length of the guide rod located above.

[0027] Preferably, the lifting mechanism includes rodless cylinders fixedly connected to both sides of the housing. A connecting block is fixedly connected between the slide block of the rodless cylinder and the housing cover. Through slots B adapted to the rodless cylinders are respectively formed in the support plate A and the support plate B. A through slot C for taking and placing the blade B is formed on one side of the inner cavity of one of the through slots B, and the through slot C corresponds to the horizontal position of the blade B.

[0028] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0029] 1. In the present invention, through the combined use of the housing, the tool A, the tool B and the displacement mechanism, the functions of edge trimming and slitting can be integrated into one. There is no need to repeatedly transfer the flame-retardant plastic film between two devices, saving the time of intermediate shutdown and repositioning, and significantly improving production continuity. Moreover, the edge trimming and slitting are carried out simultaneously, further shortening the processing cycle, which is suitable for mass production requirements. This cutting machine occupies less space and is suitable for factories with limited space. At the same time, the operator only needs to monitor one device, reducing labor costs and training complexity.

[0030] 2. In the present invention, through the combined use of the housing, the housing cover and the lifting mechanism, the tool A and the tool B can be hidden and stored, which can prevent the staff from accidentally touching the tool A and the tool B during operation, thereby improving the safety of equipment use. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1 It is a flowchart of the production method of the flame-retardant plastic film of the present invention;

[0033] Figure 2 It is a schematic structural view of the cutting machine of the present invention Figure 1 ;

[0034] Figure 3 It is a schematic structural view of the cutting machine of the present invention Figure 2 ;

[0035] Figure 4 It is a schematic view of a partial structure of the cutting machine of the present invention;

[0036] Figure 5 It is a schematic structural view of the housing, the tool A and the tool B of the cutting machine of the present invention;

[0037] Figure 6 It is a schematic sectional view of the housing of the cutting machine of the present inventionFigure 1 ;

[0038] Figure 7 Schematic cross-sectional view of the structure of the housing of the cutting machine of the present invention Figure 2 ;

[0039] Figure 8 Schematic structural diagram of tool A and the guiding member of the cutting machine of the present invention;

[0040] Figure 9 Schematic structural diagram of the movable sleeve, blade A and the connecting member of the cutting machine of the present invention;

[0041] Figure 10 Exploded schematic structural diagram of the movable sleeve, blade A and the connecting member of the cutting machine of the present invention;

[0042] Figure 11 Schematic structural diagram of tool B and the guiding member of the cutting machine of the present invention;

[0043] Figure 12 Exploded schematic structural diagram of the mounting plate and the tool body of the cutting machine of the present invention.

[0044] In the figure: 100, support plate A; 110, through slot A; 120, through slot B; 130, through slot C; 200, support plate B;

[0045] 300, guiding mechanism; 310, guiding roller; 320, adjusting roller; 330, winding roller A; 340, winding roller B; 350, I-shaped block; 360, electric telescopic rod B;

[0046] 400, housing; 410, housing cover;

[0047] 500, tool A; 510, bracket; 520, bidirectional lead screw; 530, motor A; 540, movable sleeve; 550, blade A; 551, clamping projection; 560, connecting member; 561, fixed bracket; 562, movable bracket; 563, locking member; 5631, screw; 5632, groove; 5633, screw sleeve; 564, clamping groove;

[0048] 600, tool B; 610, mounting plate; 611, limiting strip; 620, tool body; 621, connecting plate; 6211, limiting groove; 622, blade B;

[0049] 700, displacement mechanism; 710, electric telescopic rod A; 720, push plate; 730, guiding member; 731, guide rod; 732, spring;

[0050] 800, lifting mechanism; 810, rodless cylinder; 820, connecting block;

[0051] 900, motor B. Detailed implementation manners

[0052] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0053] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0054] Embodiment 1

[0055] As Figure 1 shown, a production method of a flame-retardant plastic film according to an embodiment of the present invention includes the following steps:

[0056] S1. Raw material preparation: Linear low-density polyethylene, a flame retardant, a catalyst, a coupling agent and other additives are conveyed to a homogenizing silo according to a certain ratio for stirring and mixing, and then sent into a melt granulation system for extrusion granulation to obtain a polyethylene composition;

[0057] S2. Extrusion molding: The polyethylene composition in step S1 is fed into a casting machine through a conveyor belt or a feeder to form a melt. The melting and plasticizing temperature is 170-200 °C, so that the melt is extruded through a forming die into a sheet and cast onto the roll surface of a steadily rotating cooling roll to form a film sheet, and then the film sheet is cooled and shaped on the cooling roll;

[0058] S3. Biaxial stretching: The film sheet formed in step S2 is heated on a heating roll, the heating temperature is 105-125 °C, and after holding for 15-30 min, it is sent into a film biaxial stretching device for stretching and molding. The stretched film sheet is cooled and shaped again through a cooling roll to obtain a flame-retardant plastic film;

[0059] S4. Corona treatment: The flame-retardant plastic film in step S3 is subjected to corona treatment. The electrode voltage of the corona treatment is 7.0-8.5 kV, and the intensity of the corona treatment is 40-45 dym / cm;

[0060] S5. Trimming and cutting: The corona-treated flame-retardant plastic film in step S4 is cut and trimmed by a cutting machine. The cutting machine cuts the flame-retardant plastic film into the required length and width according to customer requirements and production specifications;

[0061] S6. Packaging: The cut flame-retardant plastic film in step S5 is wound into a roll by a winding machine for easy storage and transportation. The wound flame-retardant plastic film is packaged by a packaging machine to protect it from the external environment. Finally, the packaged flame-retardant plastic film is marked with product name, specifications, batch number information, etc.

[0062] Embodiment 2

[0063] As Figures 2 - 12 shown, the difference between the production method of a flame-retardant plastic film provided in this embodiment and that in Embodiment 1 is that:

[0064] The other additives in step S1 include but are not limited to at least one of antioxidant, slip agent, and anti-sticking agent.

[0065] The cutting machine in step S5 includes support plate A100, support plate B200, guiding mechanism 300, housing 400, cutter A500, cutter B600, displacement mechanism 700, and lifting mechanism 800;

[0066] Among them, the support plate A100 and the support plate B200 have the same structural dimensions and are arranged parallel to each other. The guiding mechanism 300 is movably arranged between the support plate A100 and the support plate B200 for conveying and guiding the corona-treated flame-retardant plastic film. The housing 400 is fixedly connected between the support plate A100 and the support plate B200. One side of the housing 400 facing the conveying direction of the flame-retardant plastic film is open. A housing cover 410 that can block the open part of the housing 400 is slidably connected to the surface of the housing 400. The cutter A500 and the cutter B600 are respectively arranged up and down in the inner cavity of the housing 400. The cutter A500 is used to cut the flame-retardant plastic film into the required width, and the cutter B600 is used to cut the flame-retardant plastic film into the required length. The displacement mechanism 700 is arranged on the housing 400 for driving the cutter A500 and the cutter B600 to enter or exit the inner cavity of the housing 400. The lifting mechanism 800 is arranged on the housing 400 for driving the housing cover 410 to perform lifting operations.

[0067] The guide mechanism 300 includes a plurality of guide rollers 310 rotatably connected between the support plate A100 and the support plate B200 through bearings, an adjusting roller 320 is movably connected between the support plate A100 and the support plate B200, and a winding roller A330 and a winding roller B340 are rotatably connected between the support plate A100 and the support plate B200 through bearings. The winding roller A330 is located directly below the adjusting roller 320, and the winding roller B340 is located obliquely below the adjusting roller 320. The support plate B200 A motor B900 is installed on the side away from the support plate A100. The output shaft of the motor B900 is fixedly connected to the winding roller A330. The winding roller A330 and the winding roller B340 are connected by belt and pulley transmission. The flame-retardant plastic film after cutting can be uniformly rolled up by the winding roller A330, and the waste edges after cutting can be uniformly rolled up by the winding roller B340. Both ends of the adjusting roller 320 are rotatably connected to an I-shaped block 350 through a bearing. The support plate A100 and the support plate B200 are respectively provided with through grooves A110 adapted to the I-shaped block 350, the I-shaped block 350 and the through grooves A110 are arranged in a one-to-one correspondence, and the I-shaped block 350 is slidably connected to the inner wall surface of the corresponding through groove A110, and the inner cavity of the through groove A110 is installed with an electric telescopic rod B360, and the output end of the electric telescopic rod B360 is fixedly connected to the corresponding I-shaped block 350, and the I-shaped block 350 can be driven by starting the electric telescopic rod B360. 50 slides in the inner cavity of the corresponding through groove A110, and the I-shaped block 350 can drive the adjusting roller 320 to move synchronously between the support plate A100 and the support plate B200, thereby adjusting the tension of the flame retardant plastic film, and adjusting the distance between the adjusting roller 320 and the shell 400, thereby expanding the operable space between the adjusting roller 320 and the shell 400, so as to facilitate the subsequent disassembly, maintenance or replacement of the tool A500 and the tool B600.

[0068] Tool A500 includes a bracket 510 disposed inside the cavity of a housing 400. A two-way lead screw 520 is rotatably connected to the inside cavity of the bracket 510 through bearings. An electric motor A530 is installed on the outer surface of the bracket 510. The output shaft of the electric motor A530 penetrates into the inside cavity of the bracket 510 and is fixedly connected to one end of the two-way lead screw 520. A number of equally spaced movable sleeves 540 are movably sleeved on the surface of the two-way lead screw 520. The inner wall surfaces of the two outermost movable sleeves 540 are threadedly connected to the two-way lead screw 520, and the inner wall surfaces of the remaining movable sleeves 540 are slidably connected to the two-way lead screw 520. A number of movable sleeves 540 are connected by a scissor-link mechanism. A blade A550 is provided on one side of the movable sleeve 540 facing the adjusting roller 320. A connecting member 560 is provided between the blade A550 and the corresponding movable sleeve 540. By starting the electric motor A530, the two outermost blades A550 can be driven to move synchronously towards or away from each other, so that the distance between the two outermost blades A550 can be adjusted according to the width of the flame-retardant plastic film. At the same time, when the distance between the two outermost blades A550 is adjusted, the remaining blades A550 can be adjusted accordingly, thereby improving the adjustment efficiency of the distance between a number of blades A550.

[0069] The connecting member 560 includes a fixed frame 561 fixedly connected to one side of the movable sleeve 540. An active frame 562 is also rotatably connected to one side of the movable sleeve 540 through a rotating shaft. One ends of the fixed frame 561 and the active frame 562 penetrate to the outside of the housing 400. The blade A550 is disposed between the fixed frame 561 and the active frame 562. A locking member 563 is provided between the fixed frame 561 and the active frame 562. A clamping projection 551 is fixedly connected to both sides of the blade A550. A clamping groove 564 is respectively formed on one side of the fixed frame 561 and the active frame 562 that are symmetric to each other. The clamping projections 551 and the clamping grooves 564 are arranged in one-to-one correspondence, and the clamping projections 551 are clamped into the inner cavity of the clamping grooves 564. The locking member 563 includes a screw 5631 fixedly connected to one side of the fixed frame 561. A groove 5632 for the screw 5631 to pass through is formed on the surface of the active frame 562. A nut 5633 is threadedly sleeved on one end of the surface of the screw 5631. One side of the nut 5633 is in contact with the surface of the active frame 562. Through the connecting member 560, the connection between the blade A550 and the movable sleeve 540 can be realized to ensure the normal use of the blade A550. At the same time, the detachable connection between the connecting member 560 and the blade A550 is realized by using the locking member 563, which is convenient for subsequent replacement operation of the blade A550 and can determine the number of blades A550 used according to actual use requirements.

[0070] The cutting tool B600 includes a mounting plate 610 movably connected to the inner cavity of the housing 400 and located below the bracket 510. A cutter body 620 is provided on one side of the mounting plate 610 facing the adjusting roller 320. Both ends of the mounting plate 610 and the cutter body 620 are in contact with the inner wall surface of the housing 400. The cutter body 620 includes a connecting plate 621 provided on one side of the mounting plate 610. A blade B622 is fixedly connected to the side of the connecting plate 621 away from the mounting plate 610. A limiting strip 611 is integrally formed on one side of the mounting plate 610. A limiting groove 6211 adapted to the limiting strip 611 is formed on one side of the connecting plate 621. The inner wall surface of the limiting groove 6211 is slidably connected to the surface of the limiting strip 611. By the cooperation of the limiting strip 611 and the limiting groove 6211, the position limitation of the connecting plate 621 in the up-and-down and front-and-back directions can be realized. By the housing 400, the position limitation of the connecting plate 621 in the left-and-right direction can be realized, so as to realize the detachable connection between the mounting plate 610 and the cutter body 620, which is convenient for subsequent replacement operation of the blade B622.

[0071] The displacement mechanism 700 includes an electric telescopic rod A710 installed outside the housing 400. The output end of the electric telescopic rod A710 penetrates through the inner cavity of the housing 400 and is fixedly connected with a push plate 720. The push plate 720 is slidably connected with the inner wall surface of the housing 400. There are two sets of guide members 730 arranged up and down on the push plate 720. One set of guide members 730 is arranged corresponding to the bracket 510, and the other set of guide members 730 is arranged corresponding to the mounting plate 610. By starting the electric telescopic rod A710, the push plate 720, the guide members 730, the cutter A500 and the cutter B600 can be driven to move synchronously in the inner cavity of the housing 400, so that the cutter A500 and the cutter B600 gradually enter or extend out of the inner cavity of the housing 400; when the cutter A500 or the cutter B600 enters the inner cavity of the housing 400, the cutter A500 or the cutter B600 can be hidden and stored, which is convenient for the staff to pass the end of the flame-retardant plastic film through between the housing 400 and the adjusting roller 320 before cutting, preventing accidental contact with the blade A550 and the blade B622, and improving the use safety; when the cutter A500 or the cutter B600 extends out of the inner cavity of the housing 400, the flame-retardant plastic film can be cut, and at the same time, it is convenient to disassemble and assemble the blade A550 and the blade B622; the guide member 730 includes a guide rod 731 movably penetrating through the push plate 720. One end of the guide rod 731 extends to the outside of the housing 400. The other end of one set of guide rods 731 is fixedly connected with the surface of the bracket 510, and the other end of the other set of guide rods 731 is fixedly connected with one side of the mounting plate 610. A spring 732 is sleeved on the surface of the guide rod 731. The two ends of the spring 732 located above are respectively fixedly connected to the push plate 720 and the bracket 510, and the two ends of the spring 732 located below are respectively fixedly connected to the push plate 720 and the mounting plate 610. The guide member 730 can play a buffering role for the cutter A500 and the cutter B600, avoiding the cutter A500 and the cutter B600; the cutting edge of the blade B622 is located below the fixing frame 561. The extending length of the guide rod 731 located below is greater than that of the guide rod 731 located above, so that when the displacement mechanism 700 drives the cutter A500 and the cutter B600 to extend out of the inner cavity of the housing 400, the blade A550 can first contact the flame-retardant plastic film for width cutting, and the displacement mechanism 700 continues to operate, so that the blade B622 can then contact the flame-retardant plastic film for length cutting.

[0072] The lifting mechanism 800 includes a rodless cylinder 810 fixedly connected to both sides of the housing 400. A connecting block 820 is fixedly connected between the slider of the rodless cylinder 810 and the housing cover 410. Through grooves B120 adapted to the rodless cylinder 810 are respectively formed on the support plate A100 and the support plate B200. By starting the rodless cylinder 810, the housing cover 410 can be driven to lift at the open end of the housing 400, which can play a role of shielding and protection when the cutter A 500 and the cutter B 600 are hidden and stored, further improving the use safety. On one side of the inner cavity of one of the through grooves B120, a through groove C130 for taking and placing the blade B622 is formed. The through groove C130 corresponds to the horizontal position of the blade B622. When the tool body 620 is completely moved out of the inner cavity of the housing 400, the tool body 620 can be horizontally moved out or inserted between the support plate A100 and the support plate B200 through the through groove C130.

[0073] In this embodiment, the displacement compensation amount ΔL of the electric telescopic rod B360 is dynamically determined by the following formula:

[0074] ΔL = (k·W 2 ) / (E·t)+α·(1 - e^(-β·ΔT));

[0075] Where:

[0076] ΔL - Adjusting roller compensation displacement (mm), taking 0.01 - 0.15 mm;

[0077] W - Target cutting width (m), taken from customer order parameters;

[0078] E - Film elastic modulus (MPa), obtained in real time by an on-line detection device;

[0079] t - Film thickness (μm), obtained in real time by a laser thickness gauge;

[0080] ΔT - Ambient temperature change (°C), the temperature data of the cutting area is collected by a temperature sensor;

[0081] k - Width compensation coefficient, with a value range of 0.05 - 0.15, dynamically adjusted according to the film formula;

[0082] α - Temperature sensitivity coefficient, with a value of 0.02 - 0.1, positively correlated with the flame retardant content;

[0083] β - Temperature response attenuation factor, with a value of 0.5 - 2.0, negatively correlated with the film stretching ratio.

[0084] For example: When the production specification requires a cutting width W = 1.8 m, the on-line detection system measures that the elastic modulus of the film E = 920 MPa, the thickness t = 150 μm, and the ambient temperature rises by ΔT = 8 °C compared to the standard temperature. According to the preset parameters k = 0.12 (a larger k value is automatically selected when the formula contains a high proportion of flame retardant), α = 0.08 (the corresponding value for a flame retardant content of 12%), and β = 1.2 (the corresponding value for a biaxial stretching ratio of 3.5), the following is calculated:

[0085] ΔL = (0.12 × 1.8 2 ) / (920 × 150) + 0.08 × (1 - e^(-1.2 × 8)

[0086] = 0.00028 + 0.078 ≈ 0.078 mm

[0087] The control system drives the electric telescopic rod B(360) to move the adjusting roller(320) by 0.078 mm, and at the same time, the scissor link mechanism is linked to adjust the distance between the blades A550 to 1.8 m ± 0.05 mm.

[0088] Technical effects:

[0089] Nonlinear compensation: The square term of the width accurately reflects the edge stress concentration effect of the wide-width film;

[0090] Temperature adaptability: The exponential function compensates for the change in film ductility caused by high temperature (experiments show that for every 10 °C increase in ΔT, the cutting accuracy fluctuation decreases by 65%);

[0091] Intelligent material matching: Dynamically correct the compensation amount through the real-time feedback of the elastic modulus E (when the E value fluctuates by ±10%, the compensation error < 0.005 mm);

[0092] Process coordination: Forms a dual protection mechanism of "active compensation + passive buffering" with the spring 732.

[0093] Working principle process:

[0094] 1. The central controller receives the order parameter W;

[0095] 2. The laser thickness gauge scans the film thickness t at a frequency of 50 Hz;

[0096] 3. The tension sensor calculates E = E0 × (1 + ε) in real time, where ε is the strain correction coefficient;

[0097] 4. The temperature sensor array calculates ΔT = Taverage - Tstandard in the cutting area;

[0098] 5. Call historical production data to optimize the parameter combination of k, α, and β;

[0099] 6. Drive the electric telescopic rod B360 to perform ΔL compensation;

[0100] 7. Conduct secondary verification on the tension sensor. If the deviation > 0.01 mm, trigger iterative calculation.

[0101] Among them, the calculation process of the displacement compensation amount ΔL includes:

[0102] a) When setting the target cutting width W, the central controller calls the stored film formula parameters to automatically match the k value;

[0103] b) Calibrate the elastic modulus E in real-time through the data fed back by the film tension sensor;

[0104] c) The temperature sensor array collects the temperature data in the cutting area at a frequency of 10 Hz to calculate ΔT;

[0105] d) When ΔL > 0.03 mm, first drive the motor A530 to adjust the distance between the cutting tools A500, and then control the electric telescopic rod B360 to move the adjusting roller 320;

[0106] e) After every 50 cuts, optimize the parameter combination of α and β through least squares iteration.

[0107] For example, when the production batch is changed to a new formula containing 15% nano flame retardant:

[0108] a) The central controller automatically selects k = 0.15 (a larger width compensation corresponds to a high-fill formula);

[0109] b) The tension sensor detects that the actual E = 1050 MPa (25% higher than the standard value), and automatically corrects the calculation model;

[0110] c) The infrared temperature sensor detects that ΔT = 12 °C (due to the heat release effect of the flame retardant);

[0111] d) The system preferentially drives the motor A530 to adjust the cutting tool A500 to the target width within 0.5 s, and starts the electric telescopic rod B360 after a delay of 0.2 s;

[0112] e) After 50 cuts, according to the historical data, it is optimized to get α = 0.09 and β = 1.8 (the original values are α = 0.07 and β = 1.5).

[0113] Technical effects:

[0114] Parameter self-learning: Automatically optimize α and β through the accumulation of production data, so that the compensation accuracy increases with the production batch (the scrap rate drops to 0.3% in the 100th batch);

[0115] Timing collaborative control: The compensation action and the length difference of the guide rod 731 form an orderly cutting logic of "adjusting the width first and then the length";

[0116] Dynamic error compensation: The secondary verification mechanism eliminates the cumulative error caused by film creep;

[0117] Formulation adaptability: Automatically matches the k value for different flame retardant contents (experiments show that for every 5% increase in the flame retardant, the k value increases by 0.03).

[0118] Working principle process:

[0119] 1. When the order system issues the W value, the film formulation code is transmitted synchronously

[0120] 2. The central controller calls the formulation database to match the k reference value

[0121] 3. The high-precision encoder detects the screw rotation angle of the motor A530 and calculates the actual E value by reverse deduction

[0122] 4. The temperature compensation module calculates the weighted average ΔT=(T1×0.4 + T2×0.6), where T1 is the inlet temperature and T2 is the cutting zone temperature:

[0123] When ΔL>0.03mm:

[0124] First, control the motor A530 to complete the width positioning within 0.3 - 0.8s (the speed is positively correlated with ΔL);

[0125] After a delay of 0.1 - 0.5s, start the electric telescopic rod B360 for tension fine-tuning;

[0126] After every 50 cuts:

[0127] Extract the historical dataset of the difference between the actual and theoretical values of ΔL;

[0128] Optimize α and β by least squares fitting to minimize Σ(ΔL actual - ΔL theoretical)2.

[0129] The cutting trigger timing of the blade B622 satisfies:

[0130] t_cut = t0+(ΔL·v) / [W·ln(E / E0)];

[0131] Where:

[0132] t_cut - The delay time (s) for the blade B to start cutting;

[0133] t0 - The basic cutting time constant (0.2 - 0.5s);

[0134] v - The film conveying speed (m / s);

[0135] E0 - The standard elastic modulus (800MPa);

[0136] When it is detected that E / E0 > 1.15, the preheating device of blade B (622) is automatically activated.

[0137] For example: when the film conveying speed v = 0.6 m / s and it is detected that E = 950 MPa (E / E0 = 1.1875 > 1.15), calculate:

[0138] t_cut = 0.3 + (0.078×0.6) / [1.8×ln(950 / 800)]

[0139] = 0.3 + 0.0468 / (1.8×0.172) ≈ 0.3 + 0.15 = 0.45 s;

[0140] The system starts the cutting of blade B622 0.45 s after the trigger of tool A500 and activates the resistance heating device of blade B622 to 80°C.

[0141] Technical effects:

[0142] Delay compensation: Solve the length error caused by the springback of the high-elastic film (the measured error is reduced from ±1.2 mm to ±0.3 mm);

[0143] Material adaptability: The elastic modulus ratio triggers the heating device to prevent brittle fracture of the high-E value film;

[0144] Anti-cold cutting: Heat the blade to melt and seal the cut edge (the peel strength is increased by 23%);

[0145] Energy-saving control: Only activate heating when E / E0 > 1.15, reducing energy consumption by 37%;

[0146] Working principle process:

[0147] 1. The photoelectric encoder obtains the film conveying speed v in real time;

[0148] 2. The micro strain gauge detects the cutting resistance FR of blade B622;

[0149] 3. When FR > F standard × ln(E / E0) (F standard is the preset threshold):

[0150] a) Start the t_cut delay calculation module;

[0151] b) The piezoelectric ceramic driver fine-tunes the cutting angle θ of blade B622 = arctan(v / ΔL);

[0152] 4. After the cutting trigger:

[0153] a) The heating device heats up to T = 50 + 30×(E / E0)°C within 0.1 s;

[0154] b) The force sensor monitors the cutting process. If the FR drops suddenly by > 15%, stop immediately to prevent tearing;

[0155] 5. After cutting is completed:

[0156] a) The infrared thermal imager detects the temperature of the cut. If it is lower than Tg (glass transition temperature), an alarm is issued;

[0157] b) Reverse-correct the t0 parameter according to the actual cutting effect.

[0158] Among them, the limiting groove 6211 structure of the blade B622 provides an installation space for the heating device, ensuring that the distance between the temperature sensor and the blade surface is ≤ 0.5 mm;

[0159] The through groove C130 is designed to allow the heating blade B622 to be quickly disassembled and replaced to match cutting scenarios with different temperature requirements;

[0160] Data closed-loop: The feedback data of all sensors are connected to the central controller to form an intelligent control closed-loop of "perception - calculation - execution - verification".

[0161] Working principle:

[0162] Edge trimming operation: Start the motor A530. The motor A530 drives the bidirectional lead screw 520 to rotate. The bidirectional lead screw 520 drives the movable sleeves 540 on both sides of its surface to move towards or away from each other, so that the distance between the two outermost movable sleeves 540 can be adjusted according to the edge trimming requirements of the flame-retardant plastic film. Start the electric telescopic rod A710. The output end of the electric telescopic rod A710 drives the push plate 720, the guide rod 731, the tool A500 and the tool B600 to move synchronously towards the adjusting roller 320 until the two outermost blades A550 can contact the flame-retardant plastic film and perform edge trimming operations;

[0163] Slitting operation: While the two outermost movable sleeves 540 move on the surface of the bidirectional lead screw 520, the remaining movable sleeves 540 are driven to slide synchronously on the surface of the bidirectional lead screw 520 through the scissor link mechanism, so that the distance between two adjacent movable sleeves 540 can be adjusted, so that the cutting machine can cut the flame-retardant plastic film into the required width according to customer needs and production specifications; Start the electric telescopic rod A710 again, so that the output end of the electric telescopic rod A710 drives the push plate 720, the guide rod 731, the tool A500 and the tool B600 to continue to move towards the adjusting roller 320. The tool A500 is restricted by the adjusting roller 320. The push plate 720 squeezes the spring 732 located above, so that the spring 732 located above is forced to contract. The tool B600 continues to move until the blade B622 contacts the flame-retardant plastic film and cuts it into the required length;

[0164] Maintenance or replacement operation: Start the electric telescopic rod B360 so that the output end of the electric telescopic rod B360 drives the I-shaped block 350 to slide in the inner cavity of the through groove A110. The I-shaped block 350 drives the adjusting roller 320 to gradually move away from the housing 400 until the maximum limit. At this time, the electric telescopic rod A710 can be started so that the output end of the electric telescopic rod A710 drives the blade A550 and the tool body 620 to completely extend out of the inner cavity of the housing 400. Unscrew the groove 5632 from the screw 5631, and then flip the movable frame 562 so that the movable frame 562 drives the groove 5632 and the corresponding card slot 564 to move synchronously, and the blade A550 can be unlocked. At this time, the blade A550 can be removed from the connecting member 560 for maintenance or replacement, or the number of blades A550 used can be determined according to actual use requirements. During assembly, just operate the above steps in reverse; Horizontally move the tool body 620 so that the limiting strip 611 slides in the inner cavity of the limiting groove 6211. The connecting plate 621 and the blade B622 pass through the support plate A100 through the through groove C130 until the tool body 620 is completely separated from the mounting plate 610. At this time, the tool body 620 can be maintained or replaced. During assembly, just operate the above steps in reverse;

[0165] Hidden storage operation: Start the electric telescopic rod A710 so that the output end of the electric telescopic rod A710 drives the blade A550 and the tool body 620 to completely enter the inner cavity of the housing 400. Then start the rodless cylinder 810 so that the sliding seat of the rodless cylinder 810 drives the connecting block 820 to move. The connecting block 820 drives the housing cover 410 to move until the housing cover 410 covers the open end of the housing 400, which can prevent the blade A550 and the tool body 620 from being accidentally touched by the staff when not in use, thus improving the safety of equipment use.

[0166] Through the above specific embodiments, those skilled in the art of the present invention can easily implement the present invention. However, it should be understood that the present invention is not limited to the above specific embodiments. Based on the disclosed embodiments, those skilled in the art can arbitrarily combine different technical features to achieve different technical solutions.

Claims

1. A method for producing a flame-retardant plastic film, characterized in that, It includes the following steps: S1. Raw material preparation: Linear low-density polyethylene, a flame retardant, a catalyst, a coupling agent, and other additives are conveyed to a homogenizing silo according to a certain ratio for stirring and mixing, and then sent into a melt granulation system for extrusion granulation to obtain a polyethylene composition; S2. Extrusion molding: The polyethylene composition in step S1 is sent into a casting machine through a conveyor belt or a feeder to form a melt. The melting and plasticizing temperature is 170-200 °C, so that the melt is extruded through a forming die into a sheet and cast onto the surface of a steadily rotating cooling roller to form a film sheet, and then the film sheet is cooled and shaped on the cooling roller; S3. Biaxial stretching: The film sheet formed in step S2 is heated on a heating roller, the heating temperature is 105-125 °C, and after heat preservation for 15-30 min, it is sent into a film biaxial stretching device for stretching and molding. The stretched film sheet is cooled and shaped again through a cooling roller to obtain a flame-retardant plastic film; S4. Corona treatment: The flame-retardant plastic film in step S3 is subjected to corona treatment. The electrode voltage of the corona treatment is 7.0-8.5 kV, and the intensity of the corona treatment is 40-45 dym / cm; S5. Trimming and cutting: The corona-treated flame-retardant plastic film in step S4 is cut and trimmed by a cutting machine. The cutting machine cuts the flame-retardant plastic film into the required length and width according to customer requirements and production specifications; S6. Packaging: The cut flame-retardant plastic film in step S5 is wound into a roll by a winding machine for easy storage and transportation. The wound flame-retardant plastic film is packaged by a packaging machine to protect it from the external environment. Finally, the packaged flame-retardant plastic film is marked with product name, specifications, batch number information, etc.

2. The production method of the flame-retardant plastic film according to claim 1, characterized in that: The other additives in step S1 include but are not limited to at least one of an antioxidant, a slip agent, and an anti-sticking agent.

3. The production method of the flame-retardant plastic film according to claim 1, characterized in that: The cutting machine in step S5 includes a support plate A (100), a support plate B (200), a guiding mechanism (300), a housing (400), a cutter A (500), a cutter B (600), a displacement mechanism (700), and a lifting mechanism (800); The support plate A (100) and the support plate B (200) have the same structural dimensions and are arranged parallel to each other; the guide mechanism (300) is movably arranged between the support plate A (100) and the support plate B (200) for conveying and guiding the flame-retardant plastic film after corona treatment; the shell (400) is fixedly connected between the support plate A (100) and the support plate B (200); the shell (400) is arranged in an open shape on one side facing the conveying direction of the flame-retardant plastic film; and a shell cover capable of covering the open part of the shell (400) is slidably connected to the surface of the shell (400). (410), the tool A (500) and the tool B (600) are respectively arranged in the inner cavity of the shell (400) from top to bottom, the tool A (500) is used to cut the flame retardant plastic film into a desired width, and the tool B (600) is used to cut the flame retardant plastic film into a desired length, the displacement mechanism (700) is arranged on the shell (400) and is used to drive the tool A (500) and the tool B (600) to enter or extend out of the inner cavity of the shell (400), and the lifting mechanism (800) is arranged on the shell (400) and is used to drive the shell cover (410) to perform lifting operations.

4. The production method of the flame-retardant plastic film according to claim 3, characterized in that: The guide mechanism (300) comprises a plurality of guide rollers (310) rotatably connected between the support plate A (100) and the support plate B (200); an adjusting roller (320) is movably connected between the support plate A (100) and the support plate B (200); a winding roller A (330) and a winding roller B (340) are also rotatably connected between the support plate A (100) and the support plate B (200); the winding roller A (330) is located directly below the adjusting roller (320); the winding roller B (340) is located obliquely below the adjusting roller (320); a motor B (900) is installed on the side of the support plate B (200) away from the support plate A (100); an output shaft of the motor B (900) is connected to the winding roller A (330) is fixedly connected to the winding roller A (330) and the winding roller B (340) is transmission-connected, and both ends of the adjusting roller (320) are rotatably connected to an I-shaped block (350), and a through groove A (110) adapted to the I-shaped block (350) is respectively opened on the support plate A (100) and the support plate B (200), and the I-shaped block (350) and the through groove A (110) are arranged in a one-to-one correspondence, and the I-shaped block (350) is slidably connected to the inner wall surface of the corresponding through groove A (110), and an electric telescopic rod B (360) is installed in the inner cavity of the through groove A (110), and the output end of the electric telescopic rod B (360) is fixedly connected to the corresponding I-shaped block (350).

5. The production method of the flame-retardant plastic film according to claim 4, characterized in that: The tool A (500) includes a bracket (510) disposed in the inner cavity of the housing (400). A bidirectional lead screw (520) is rotatably connected in the inner cavity of the bracket (510). A motor A (530) is installed on the outer surface of the bracket (510). The output shaft of the motor A (530) penetrates into the inner cavity of the bracket (510) and is fixedly connected to one end of the bidirectional lead screw (520). A plurality of equally spaced movable sleeves (540) are movably sleeved on the surface of the bidirectional lead screw (520). The inner wall surfaces of the two outermost movable sleeves (540) are threadedly connected to the bidirectional lead screw (520), and the inner wall surfaces of the remaining movable sleeves (540) are slidably connected to the bidirectional lead screw (520). A plurality of the movable sleeves (540) are connected by a scissor link mechanism. A blade A (550) is provided on the side of the movable sleeve (540) facing the adjusting roller (320). A connecting member (560) is provided between the blade A (550) and the corresponding movable sleeve (540).

6. The production method of the flame-retardant plastic film according to claim 5, characterized in that: The connecting member (560) includes a fixed frame (561) fixedly connected to one side of the movable sleeve (540). A movable frame (562) is also rotatably connected to one side of the movable sleeve (540). One ends of the fixed frame (561) and the movable frame (562) penetrate to the outside of the housing (400). The blade A (550) is disposed between the fixed frame (561) and the movable frame (562). A locking member (563) is provided between the fixed frame (561) and the movable frame (562). A clamping projection (551) is fixedly connected to both sides of the blade A (550). A clamping groove (564) is respectively formed on one side of the fixed frame (561) and the movable frame (562) that are symmetric to each other. The clamping projection (551) and the clamping groove (564) are arranged in one-to-one correspondence. The clamping projection (551) is clamped into the inner cavity of the clamping groove (564); Among them, the locking member (563) includes a screw rod (5631) fixedly connected to one side of the fixed frame (561). A groove (5632) for the screw rod (5631) to pass through is formed on the surface of the movable frame (562). A nut sleeve (5633) is threadedly sleeved on one end of the surface of the screw rod (5631). One side of the nut sleeve (5633) is in contact with the surface of the movable frame (562).

7. The production method of the flame-retardant plastic film according to claim 6, characterized in that: The tool B (600) includes a mounting plate (610) movably connected in the inner cavity of the housing (400) and located below the bracket (510). A tool body (620) is provided on the side of the mounting plate (610) facing the adjusting roller (320). Both ends of the mounting plate (610) and the tool body (620) are in contact with the inner wall surface of the housing (400); Among them, the tool body (620) includes a connecting plate (621) provided on one side of the mounting plate (610). A blade B (622) is fixedly connected to the side of the connecting plate (621) away from the mounting plate (610). A limiting strip (611) is integrally formed on one side of the mounting plate (610). A limiting groove (6211) adapted to the limiting strip (611) is formed on one side of the connecting plate (621). The inner wall surface of the limiting groove (6211) is slidably connected to the surface of the limiting strip (611).

8. The production method of the flame-retardant plastic film according to claim 7, characterized in that: The displacement mechanism (700) includes an electric telescopic rod A (710) installed on the outer side of the housing (400). The output end of the electric telescopic rod A (710) penetrates into the inner cavity of the housing (400) and is fixedly connected to a push plate (720). The push plate (720) is slidably connected to the inner wall surface of the housing (400). Two sets of guiding members (730) arranged vertically are provided on the push plate (720). One set of the guiding members (730) is correspondingly arranged with the bracket (510), and the other set of the guiding members (730) is correspondingly arranged with the mounting plate (610). Among them, the guiding member (730) includes a guide rod (731) movably penetrating through the push plate (720). One end of the guide rod (731) extends to the outside of the housing (400). The other end of one set of the guide rods (731) is fixedly connected to the surface of the bracket (510), and the other end of the other set of the guide rods (731) is fixedly connected to one side of the mounting plate (610). A spring (732) is sleeved on the surface of the guide rod (731). The two ends of the spring (732) located above are respectively fixedly connected to the push plate (720) and the bracket (510), and the two ends of the spring (732) located below are respectively fixedly connected to the push plate (720) and the mounting plate (610).

9. The production method of the flame-retardant plastic film according to claim 8, characterized in that: The cutting edge of the blade B (622) is located below the fixed frame (561). The extension length of the guide rod (731) located below is greater than the extension length of the guide rod (731) located above.

10. The production method of the flame-retardant plastic film according to claim 7, characterized in that: The lifting mechanism (800) includes a rodless cylinder (810) fixedly connected to both sides of the housing (400). A connecting block (820) is fixedly connected between the sliding seat of the rodless cylinder (810) and the housing cover (410). Through grooves B (120) adapted to the rodless cylinder (810) are respectively formed on the support plate A (100) and the support plate B (200). A through groove C (130) for taking and placing the blade B (622) is formed on one side of the inner cavity of one of the through grooves B (120). The through groove C (130) corresponds to the horizontal position of the blade B (622).

Images