Plastic film extrusion equipment

Abstract

The invention belongs to the field of film extrusion, and particularly relates to plastic film extrusion equipment which comprises a rack, and a film blowing machine die head used for extruding a blown tubular film, a traction mechanism used for flattening and pulling the tubular film and two pairs of first support arms are fixedly arranged on one side of the rack; a first roller group and a second roller group which are used for furling and extruding the tubular film, and a switching assembly for replacing the positions of the first roller group and the second roller group are arranged between each pair of first support arms in a staggered manner; the switching assembly comprises a rack arranged on one first supporting arm and a power source used for driving the rack to slide along the first supporting arm. By arranging the switching assembly, the first roller set can be rapidly replaced by the second roller set, so that the operation during maintenance and replacement of the first roller set is simplified, and the shutdown maintenance time is shortened.

Description

Technical Field

[0001] This invention relates to the field of film extrusion, specifically to a plastic film extrusion device. Background Technology

[0002] Plastic film is an extremely thin, flexible, and tough plastic product widely used in all aspects of daily life, from food packaging and agricultural mulch to shopping bags and protective coverings. It is mainly made of polymers such as polyethylene (PE) and polypropylene (PP), and features lightweight, waterproof properties, good chemical stability, and high plasticity, making it an indispensable basic material in modern packaging and protection.

[0003] Plastic film is mainly produced through blow molding extrusion. Its basic working principle is as follows: plastic granules are heated and melted, then extruded through a ring-shaped die to form a hollow, thin-walled film bubble. Simultaneously, compressed air is injected into the bubble, causing it to inflate and stretch upwards like a balloon. Subsequently, this tubular film bubble is gradually gathered and folded into a flat, double-layered film by a herringbone roller device above. Finally, a set of extrusion rollers flattens it and pulls it to a winding device to complete the winding process.

[0004] During the above-mentioned process, the herringbone rollers will gradually wear down due to long-term high-speed friction with the film and contact with high-temperature film bubbles, which directly affects the product quality of the film. Therefore, once the wear is severe and it needs to be repaired or replaced, the entire production line must be shut down and the rollers must be cooled down before they can be disassembled, repaired and recalibrated. This process usually takes a long time and is difficult to meet the actual needs of current film production.

[0005] Therefore, a plastic film extrusion device is proposed to address the above problems. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by the present invention to solve its technical problem is as follows: A plastic film extrusion device of the present invention includes a frame, on one side of which is fixed a blown film die head for extruding blown tubular film, a traction mechanism for flattening and pulling the tubular film, and two pairs of first arms; between each pair of first arms are staggered first roller groups and second roller groups for gathering and squeezing the tubular film, and a switching component for replacing the positions of the first roller groups and the second roller groups; by setting the switching component, the second roller group can quickly replace the first roller group, thereby simplifying the operation of the maintenance and replacement of the first roller group and shortening the downtime for maintenance.

[0008] Preferably, the switching assembly includes a rack mounted on one of the first arms and a power source for driving the rack to slide along the first arm; the bottom of the rack is engaged with a gear rotatably mounted on the outer wall of the first arm; a dial is fixedly connected to the outer wall of the gear; second grooved wheels rotatably mounted on the outer wall of the first arm are symmetrically engaged on both sides of the dial; a pair of second grooved wheels are respectively fixedly connected to the first roller group and the second roller group; through the cooperative action of the dial, the first grooved wheel, and the second grooved wheel, the dial can rotate with the gear and successively engage with the first grooved wheel and the second grooved wheel, so that the second roller group can be in working state simultaneously with the first roller group before the first roller group is deflected away, realizing the online replacement of the first roller group by the device, simplifying the traditional operation that requires shutdown for maintenance.

[0009] Preferably, the first roller group and the second roller group include a second support arm eccentrically connected to the second grooved roller; a distributor is fixedly connected to the outer wall of the second support arm; the outer wall of the distributor is fixedly provided with a pair of pipe openings and rotatably provided with a plurality of first guide rollers, and the first guide rollers, the distributor, and the pipe openings are connected; during the overflow process of the cooling medium, it can be filled into the first guide roller to absorb and cool the heat of the outer wall of the first guide roller, which can assist the original cooling and shaping of the film on the one hand, and reduce the friction coefficient of the film surface on the other hand, thereby reducing the friction between the film and the first guide roller and extending the service life of the first guide roller.

[0010] Preferably, a water-blocking block is fixed to the inner wall of the first guide roller; by setting the water-blocking block, which is concentric with the first guide roller, the central area of ​​the first guide roller can be filled, so that when the cooling medium fills the inside of the first guide roller, the flow area of ​​the medium in the first guide roller is reduced, thereby accelerating the flow rate of the medium in the first guide roller and improving the heat exchange effect of the cooling medium on the first guide roller.

[0011] Preferably, a drain outlet is provided at the end of the first guide roller at the bottom. By providing a drain outlet, when the original first roller assembly is switched to the stop position, the delivery pump of its corresponding cooling circuit is also stopped. That is, a small amount of cooling medium will accumulate in the first guide roller and the distributor. Before disassembling and replacing the first roller assembly, it can be connected to the drain outlet through a negative pressure device. The negative pressure device is preferably a self-priming pump to extract the residual cooling medium in the first guide roller and the distributor, so as to avoid the waste of coolant.

[0012] Preferably, the outer wall of the first guide roller is provided with a guide groove; the guide groove provided on the outer wall of the first guide roller can make the middle area of ​​the first guide roller recessed and the two sides raised. In addition, the recessed area is the contact area between the first guide roller and the film bubble. This setting can help the film bubble move in the center position of the first guide roller and reduce the deviation of the film bubble during the blow molding process.

[0013] Preferably, a protective layer is fixedly provided on the outer wall of the guide groove. By providing the protective layer, which is made of antistatic material and is detachably connected to the guide groove, the protective layer can be antistatic cloth or tape. On the one hand, the protective layer can reduce the static electricity generated by friction when the first guide roller contacts the film bubble and reduce the wear caused by direct contact between the first guide roller and the film bubble. On the other hand, the protective layer can be detachably installed on the guide groove by Velcro or pressure-sensitive adhesive. By replacing the protective layer, the contact surface on the first guide roller can be replaced, thereby reducing the material waste caused by replacing all the first guide rollers.

[0014] Preferably, a support plate is fixedly provided on one side of the frame; multiple frames are provided on the support plate; multiple second guide rollers are rotatably provided on the side of the frame facing the film; by setting multiple frames, the frames can play a limiting role in the upward movement of the film bubble through the second guide rollers, so as to ensure that the film bubble can stably contact the first roller group or the second roller group located at the work station, and avoid interference between the film bubble and the first roller group or the second roller group in the stopped state.

[0015] Preferably, the support plate has an upright plate on top; the frame is rotatably provided with a screw threadedly connected to the upright plate on the side opposite to the second guide roller, and a crossbar is fixedly provided that slides through the upright plate; by setting the screw, the screw can be manually rotated to make the screw and the upright plate move radially through the screw drive. During the process, due to the guide limit of the crossbar on the frame, the frame can move radially together with the screw, so that the position of the frame can be adjusted by the device to meet more production needs.

[0016] Preferably, the bottom of the support plate is provided with a rotatable ring; the outer wall of the ring is provided with multiple arc-shaped grooves, and the outer wall of the support plate is provided with multiple radial grooves; a fixing pin is also fixedly connected to the side of the frame away from the second guide roller, which is in sliding fit with both the arc-shaped grooves and the radial grooves; by setting the ring and the fixing pin, when the rotating screw drives the directly connected frame to move radially, the fixing pin of the frame directly connected at this point can slide along the radial groove, and the bottom ring will rotate through the arc-shaped groove. When the ring rotates, it can drive the fixing pins at the other arc-shaped grooves, that is, the other frames move synchronously, so as to realize the synchronous adjustment of multiple frames.

[0017] The advantages of this invention are: 1. The plastic film extrusion equipment of the present invention, by setting a switching component, enables the second roller group to quickly replace the first roller group, thereby simplifying the operation of the maintenance and replacement of the first roller group and shortening the downtime for maintenance.

[0018] 2. The plastic film extrusion equipment of the present invention, through the cooperation of the dial, the first grooved wheel and the second grooved wheel, the dial can rotate with the gear and successively mesh with the first grooved wheel and the second grooved wheel, so that the second roller group can be in working state at the same time as the first roller group, and then the first roller group can be deflected away, realizing the online replacement of the first roller group by the device, simplifying the traditional operation that requires shutdown for maintenance. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the main body of the present invention; Figure 2 This is a schematic diagram of the structure of the blown film machine die head in this invention; Figure 3 This is a schematic diagram of the structure of the first arm in this invention; Figure 4 This is a schematic diagram of the structure of the first roller group in this invention; Figure 5 This is a schematic diagram of the structure of the second roller group in this invention; Figure 6 This is a schematic diagram of the structure of the second grooved wheel in this invention; Figure 7 This is a schematic diagram of the dial structure in this invention; Figure 8 This is a schematic diagram of the distributor in this invention; Figure 9 This is a schematic diagram of the structure of the first guide roller in this invention; Figure 10 This is a schematic diagram of the frame structure in this invention.

[0021] In the diagram: 1. Frame; 12. Blown film die head; 13. Traction mechanism; 14. First support arm; 15. First roller group; 16. Second roller group; 2. Rack; 22. Gear; 23. Dial; 24. First grooved wheel; 25. Second grooved wheel; 3. Second support arm; 32. First guide roller; 33. Distributor; 34. Pipe opening; 4. Water-blocking block; 5. Drain outlet; 6. Guide groove; 7. Protective layer; 8. Frame; 82. Second guide roller; 83. Support plate; 9. Screw; 92. Crossbar; 93. Vertical plate; 1001. Ring; 1002. Fixing pin. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Specific implementation examples are given below.

[0024] Please see Figures 1 to 10 As shown in the figure, a plastic film extrusion device according to an embodiment of the present invention includes a frame 1. A blown film die head 12 for extruding blown tubular film, a traction mechanism 13 for flattening and pulling the tubular film, and two pairs of first support arms 14 are fixedly provided on one side of the frame 1. A first roller group 15 and a second roller group 16 for gathering and squeezing the tubular film are alternately provided between each pair of first support arms 14, and a switching component for replacing the positions of the first roller group 15 and the second roller group 16. During operation, the blown film die head 12 is connected to the extruder (feeding device) through a pipe. The high-temperature fluid melt output from the extruder passes through the blown film die head 12 and is extruded from the annular gap. Combined with the compressed gas introduced into the center of the blown film die head 12, a hollow tubular film bubble can be formed. When the tubular film bubble passes through the two pairs of first support arms 14, it can be smoothly gathered and folded into a sheet film by a pair of "V"-shaped first roller groups 15. Subsequently, the sheet film can pass through the traction mechanism 13. The traction mechanism 13 can provide a stable traction force to flatten the sheet film and output it to the next process equipment (such as a winding machine). The equipment involved in the above process are all mature technologies, so they will not be elaborated here. After prolonged use, the surface of the first roller group 15 is prone to severe wear due to friction and high temperature. At this time, the switching component can be used to drive the first roller group 15 and the second roller group 16 to replace each other, so as to replace the severely worn first roller group 15 and install the brand-new second roller group 16 at the work station, thereby realizing the rapid replacement of the first roller group 15. By setting up the switching component, the second roller group 16 can quickly replace the first roller group 15, thereby simplifying the operation of maintenance and replacement of the first roller group 15 and shortening the downtime for maintenance.

[0025] Please see Figures 3 to 7 As shown, the switching assembly includes a rack 2 mounted on one of the first arms 14 and a power source for driving the rack 2 to slide along the first arm 14; the bottom of the rack 2 is engaged with a gear 22 rotatably mounted on the outer wall of the first arm 14; a dial 23 is fixedly connected to the outer wall of the gear 22; second grooved wheels 25 rotatably mounted on the outer wall of the first arm 14 are symmetrically engaged on both sides of the dial 23; a pair of second grooved wheels 25 are fixedly connected to the first roller group 15 and the second roller group 16 respectively; The initial state can be as follows Figure 4 As shown, the first roller assembly 15 is in the working position, and the rack 2 is at its highest point. When the first roller assembly 15 needs to be replaced, the power source can be activated to drive the rack 2 to retract and move downward. The power source is preferably a cylinder. When the rack 2 moves, it can mesh with the gear 22, causing the gear 22 to drive the directly connected dial 23 to rotate counterclockwise. The dial 23 can first mesh with the first grooved wheel 24 and drive the first grooved wheel 24 to deflect clockwise. At this time, if... Figure 5 As shown, the first grooved wheel 24 can drive the directly connected second roller group 16 to rotate to a state where it is aligned with the first roller group 15. That is, both the first roller group 15 and the second roller group 16 are in working state. Since the first roller group 15 has previously applied guidance and compression during the conveying of the membrane bubble, the tension on the membrane bubble will not change abruptly when the second roller group 16 is aligned with the first roller group 15. In addition, since the rollers on the second roller group 16 and the first roller group 15 are staggered, there is no spatial interference between them when the second roller group 16 deflects in space. At this time, the gear 22 and the dial 23 have not rotated half a revolution. Then the dial 23 continues to rotate one arc length. During this stroke, both the second roller group 16 and the first roller group 15 are in a working state of applying compression to the membrane bubble, that is, the membrane bubble is always in a stable state until the dial 23 meshes with the second grooved wheel 25. The second grooved wheel 25 can drive the directly connected first roller group 15 to deflect counterclockwise. At this time, as Figure 6 As shown, the second roller group 16 is in the working position, while the first roller group 15 is in the stopped state. The gear 22 and the dial 23 have not rotated a full revolution. When the rack 2 finally stops sliding, it should be ensured that the remaining rotation amplitude of the gear 22 will not mesh with the first grooved wheel 24. That is, it is best if the gear 22 rotates only one revolution in the entire movement process. Through the cooperation of the dial 23, the first grooved wheel 24, and the second grooved wheel 25, the dial 23 can rotate with the gear 22 and successively mesh with the first grooved wheel 24 and the second grooved wheel 25. This allows the second roller group 16 to be in the working state at the same time as the first roller group 15, and then the first roller group 15 can be deflected away. This allows the first roller group 15 to be removed from the film bubble blow molding production line and to be in a stopped state. This makes it convenient for operators to replace the first roller group 15 online, simplifying the traditional operation that requires stopping the machine for maintenance.

[0026] Please see Figure 8 and Figure 9 As shown, the first roller group 15 and the second roller group 16 include a second support arm 3 eccentrically connected to the second grooved wheel 25; a distributor 33 is fixedly connected to the outer wall of the second support arm 3; a pair of pipe openings 34 are fixedly provided on the outer wall of the distributor 33 and a plurality of first guide rollers 32 are rotatably provided, and the first guide rollers 32, the distributor 33 and the pipe openings 34 are connected to each other. The only difference between the first roller group 15 and the second roller group 16 is their position; the rest are the same. Taking the first roller group 15 as an example, when it gathers the film bubble, the cooling medium in the container can be transported to the distributor 33 through the pipe 34 by activating the delivery pump connected to the end of the bottom pipe 34. Water is preferred as the cooling medium. The cooling medium can overflow into the cooling mechanism through the top pipe 34, and after re-cooling, it is sent back to the container for the next cycle of cooling. During the overflow of the cooling medium, it can fill into the first guide roller 32 to absorb and cool the heat on the outer wall of the first guide roller 32. On the one hand, it can reduce the temperature of the film in contact with the first guide roller 32, thereby reducing the melting and adhesion of the film due to its own heat, and assisting in the original cooling and shaping of the film. On the other hand, it can also reduce the temperature of the first guide roller 32, reducing the bending or deformation caused by the first guide roller 32 due to its own thermal expansion caused by absorbing heat transferred from the film, and extending the service life of the first guide roller 32.

[0027] Please see Figure 9 As shown, a water-blocking block 4 is fixedly connected to the inner wall of the first guide roller 32; By setting up a water-blocking block 4, which is concentrically set with the first guide roller 32, the central area of ​​the first guide roller 32 can be filled. This reduces the flow area of ​​the medium in the first guide roller 32 when the cooling medium fills the interior of the first guide roller 32, thereby accelerating the flow rate of the medium in the first guide roller 32 and improving the heat exchange effect of the cooling medium on the first guide roller 32.

[0028] Please see Figure 8 and Figure 9 As shown, the first guide roller 32 located at the bottom has a drain outlet 5 at its end; By setting up a drain outlet 5, when the original first roller group 15 is switched to the stop position, the corresponding cooling circuit delivery pump is also stopped. That is, a small amount of cooling medium will accumulate in the first guide roller 32 and the distributor 33. Before disassembling and replacing the first roller group 15, it can be connected to the drain outlet 5 through a negative pressure device. The negative pressure device is preferably a self-priming pump to extract the residual cooling medium in the first guide roller 32 and the distributor 33, so as to avoid the waste of coolant.

[0029] Please see Figure 9 As shown, the outer wall of the first guide roller 32 is provided with a guide groove 6; The guide groove 6 on the outer wall of the first guide roller 32 can make the middle area of ​​the first guide roller 32 concave and the two sides protruding. In addition, the concave area is the contact area between the first guide roller 32 and the bubble. This setting can help the bubble move in the center position of the first guide roller 32 and reduce the deviation of the bubble during the blow molding process.

[0030] Please see Figure 9 As shown, a protective layer 7 is fixedly provided on the outer wall of the guide groove 6; By setting a protective layer 7, which is made of anti-static material and is detachably connected to the guide groove 6, the protective layer 7 can be made of anti-static cloth or tape. On the one hand, the protective layer 7 can reduce the static electricity generated by friction when the first guide roller 32 contacts the membrane bubble, and reduce the wear caused by direct contact between the first guide roller 32 and the membrane bubble. On the other hand, the protective layer 7 can be detachably installed on the guide groove 6 by Velcro or pressure-sensitive adhesive. By replacing the protective layer 7, the contact surface on the first guide roller 32 can be replaced, thereby reducing the material waste caused by replacing all the first guide rollers 32.

[0031] Please see Figure 1 and Figure 10 As shown, a support plate 83 is also fixedly provided on one side of the frame 1; a plurality of frames 8 are provided on the support plate 83; a plurality of second guide rollers 82 are rotatably provided on the side of the frame 8 facing the film; By setting multiple frames 8, the frames 8 can limit the upward movement of the membrane bubble through the second guide roller 82, so as to ensure that the membrane bubble can stably contact the first roller group 15 or the second roller group 16 located at the work station, and avoid interference between the membrane bubble and the first roller group 15 or the second roller group 16 in the stopped state.

[0032] Please see Figure 10 As shown, the support plate 83 has a vertical plate 93 on its top; the frame 8 is rotatably provided with a screw 9 that is threadedly connected to the vertical plate 93 on the side opposite to the second guide roller 82, and a crossbar 92 that slides through the vertical plate 93 is fixedly provided. By setting the screw 9, manual rotation of the screw 9 can cause the screw 9 and the vertical plate 93 to move radially through threaded transmission. During the process, due to the guide limit of the crossbar 92 on the frame 8, the frame 8 can move radially together with the screw 9, realizing the adjustable position of the frame 8 and meeting more production needs.

[0033] Please see Figure 10 As shown, the bottom of the support plate 83 is provided with a circular ring 1001; the outer wall of the circular ring 1001 is provided with multiple arc-shaped grooves, and the outer wall of the support plate 83 is provided with multiple radial grooves; the frame 8 is also fixedly connected to the side opposite to the second guide roller 82 with a fixing pin 1002 that is in sliding fit with the arc-shaped grooves and radial grooves. By setting up a ring 1001 and a fixing pin 1002, when the rotating screw 9 drives the directly connected frame 8 to move radially, the fixing pin 1002 directly connected to the frame 8 can slide along the radial groove, and the bottom ring 1001 will rotate through the arc groove. When the ring 1001 rotates, it can drive the fixing pins 1002 at the other arc grooves, that is, the other frames 8 move synchronously, so as to realize the synchronous adjustment of multiple frames 8.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A plastic film extrusion device, comprising a frame (1), characterized in that: The frame (1) is fixedly provided with a blown film die head (12) for extruding and blowing tubular films, a traction mechanism (13) for flattening and pulling tubular films, and two pairs of first arms (14) on one side. Each pair of the first arms (14) is provided with an alternating first roller group (15) and a second roller group (16) for gathering and squeezing the tubular film, and a switching assembly for replacing the positions of the first roller group (15) and the second roller group (16).

2. The plastic film extrusion equipment according to claim 1, characterized in that: The switching assembly includes a rack (2) disposed on one of the first arms (14) and a power source for driving the rack (2) to slide along the first arm (14); the bottom of the rack (2) is engaged with a gear (22) that is rotatably disposed on the outer wall of the first arm (14). The gear (22) has a dial (23) fixedly connected to its outer wall; the dial (23) has a second grooved wheel (25) symmetrically meshed on both sides and rotatably mounted on the outer wall of the first support arm (14); the pair of second grooved wheels (25) are fixedly connected to the first roller group (15) and the second roller group (16) respectively.

3. The plastic film extrusion equipment according to claim 2, characterized in that: The first roller group (15) and the second roller group (16) include a second support arm (3) eccentrically connected to the second grooved wheel (25); a distributor (33) is fixedly connected to the outer wall of the second support arm (3); a pair of pipe openings (34) are fixedly provided on the outer wall of the distributor (33) and a plurality of first guide rollers (32) are rotatably provided, and the first guide rollers (32), the distributor (33) and the pipe openings (34) are connected.

4. A plastic film extrusion device according to claim 3, characterized in that: A water-blocking block (4) is fixed to the inner wall of the first guide roller (32).

5. A plastic film extrusion device according to claim 4, characterized in that: The first guide roller (32) located at the bottom has a drain outlet (5) at its end.

6. A plastic film extrusion device according to claim 5, characterized in that: The outer wall of the first guide roller (32) is provided with a guide groove (6).

7. A plastic film extrusion device according to claim 6, characterized in that: The outer wall of the guide groove (6) is fixedly provided with a protective layer (7).

8. A plastic film extrusion device according to claim 7, characterized in that: A support plate (83) is also fixedly provided on one side of the frame (1); a plurality of frames (8) are provided on the support plate (83); a plurality of second guide rollers (82) are provided on the side of the frame (8) facing the film.

9. A plastic film extrusion device according to claim 8, characterized in that: The support plate (83) has a vertical plate (93) on its top; the frame (8) is provided with a screw (9) that is threadedly connected to the vertical plate (93) on the side away from the second guide roller (82), and a crossbar (92) that slides through the vertical plate (93) is fixedly provided.

10. A plastic film extrusion device according to claim 9, characterized in that: The bottom of the support plate (83) is provided with a rotating ring (1001); the outer wall of the ring (1001) is provided with multiple arc grooves, and the outer wall of the support plate (83) is provided with multiple radial grooves; the frame (8) is also fixedly connected to a fixed pin (1002) on the side away from the second guide roller (82), which is in sliding fit with the arc grooves and radial grooves.

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