Thin film hot melt extruder for packaging bag thin film production

Abstract

The invention relates to the technical field of extrusion equipment, in particular to a film hot melt extruder for packaging bag film production, which comprises a die head, an outer die, an inner die, a center die, a plurality of rotating rings and a scraper, the multi-layer die head comprises the outer die, the inner die and the center die, adjacent side walls of the outer die, the inner die and the center die form an extrusion runner, and the rotating rings are coaxially, horizontally and rotatably mounted in the multi-layer die head. A plurality of scrapers are installed on the rotating ring and located in the extrusion runner, the section width of the scrapers is equal to that of the extrusion runner, a driving assembly is arranged in the multi-layer die head and connected with the rotating ring, and the driving assembly drives the rotating ring to drive the scrapers to rotate around the axis through power of a cleaning agent injected into the feeding port. According to the device, the rotating ring and the scraper are driven by the driving assembly to rotate so as to scrape the extrusion runner, the problems of safety risk and high cost caused by manual disassembly and assembly are avoided, and the cleaning cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of extrusion equipment, and particularly to a film hot-melt extruder for producing packaging bag films. Background Art

[0002] A film hot-melt extruder is a key equipment for plastic film production and processing. It is mainly used to melt materials and then extrude and form them through a specific die. Among them, the rotary film hot-melt extruder distributes materials step by step in the circumferential direction through a spiral flow channel, so that the produced materials form a film with more uniform thickness and good physical properties in the circumferential direction, occupying an important position in many film production fields such as packaging and agriculture.

[0003] After the existing film hot-melt extruder is extruded and formed, there will be residual materials attached in its forming cavity. However, it is very inconvenient to clean these residual materials. Once the residual materials solidify, it will have an adverse impact on the forming quality of the film when the extrusion operation is carried out again later, resulting in obstacles to the processing process. For this, a solution is provided in the prior art. For example, the patent application number CN202223155649.X provides an extrusion forming die head for multi-layer composite pipes. This patent provides an extrusion forming die head for multi-layer composite pipes, including an extrusion head. A connecting piece is arranged on the right side of the extrusion head and a die head body detachably connected through the connecting piece. A mandrel is detachably installed in the die head body, and an extrusion cavity is formed between the mandrel and the inner wall of the die head body. A plurality of feed pipes extending into the extrusion cavity are installed at the left end of the die head body. This extrusion forming die head for multi-layer composite pipes can conveniently install the die head body on the extrusion head through the connecting piece, add auxiliary materials into the extrusion cavity through the feed pipes, and make it better formed through heating components. After the extrusion forming process, the die head body can be removed, and the connecting disk and the locking ring can be separated through a spring-back plug, so as to conveniently and quickly take out the mandrel, facilitating the staff to clean the inside of the extrusion cavity, thereby avoiding the solidification of residual materials and affecting the quality of the extruded pipes. However, in the prior art, the mandrel still needs to be manually taken out for cleaning. Manual disassembly and cleaning not only consume manpower but also increase the operation time of cleaning, affecting the efficiency of the entire extrusion forming operation. Summary of the Invention

[0004] The purpose of the present invention is to provide a film hot-melt extruder for producing packaging bag films, so as to solve the problem that manual disassembly and cleaning during die head cleaning not only consume manpower but also increase the operation time of cleaning, affecting the efficiency of the entire extrusion forming operation.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A film hot-melt extruder for producing packaging bag films, comprising an extrusion device, a multi-layer die head, an outer die, an inner die, a central die, a rotating ring and a scraper. The multi-layer die head is installed on the frame. The multi-layer die head includes an outer die, an inner die and a central die. Spiral grooves are formed on the outer walls of the inner die and the central die. The outer die, the inner die and the central die are coaxially installed from outside to inside. The adjacent side walls of the outer die, the inner die and the central die form an extrusion flow channel. The multi-layer die head is provided with a feed inlet and an extrusion outlet. The extrusion flow channel is respectively communicated with the feed inlet and the extrusion outlet. The feed inlet is connected to the extrusion device through a material pipe. The connection between the feed inlet and the extrusion flow channel is located in the spiral groove. The depth of the horizontal cross-section of the spiral groove decreases along the axis towards the extrusion outlet. A plurality of rotating rings are coaxially and horizontally rotatably installed in the multi-layer die head. A plurality of scrapers are installed on the rotating ring. The scraper is located in the extrusion flow channel, and the cross-sectional width of the scraper is equal to the cross-sectional width of the extrusion flow channel. A driving component is arranged in the multi-layer die head. The driving component is connected to the rotating ring. The driving component drives the rotating ring to drive the scraper to rotate around the axis with the power of the cleaning agent injected into the feed inlet.

[0007] It is easy to understand that when it is necessary to clean the multi-layer die head, the driving component drives the rotating ring to drive the scraper to rotate around the axis with the power of the cleaning agent injected into the feed inlet. Since the cross-sectional width of the scraper is equal to the cross-sectional width of the extrusion flow channel, at this time, the side wall of the scraper scrapes the extrusion flow channel in the multi-layer die head. At the same time, under the joint action of the cleaning agent, the impurities and waste are discharged from the extrusion outlet together with the cleaning agent to achieve the purpose of cleaning. By driving the rotating ring to rotate through the driving component, the scraper is driven to scrape the waste impurities in the extrusion flow channel, avoiding manual disassembly and cleaning, thus avoiding the safety problems caused by mistakes due to improper operation, and at the same time reducing the labor cost and improving the efficiency of the entire extrusion molding operation.

[0008] Preferably, the driving component includes blades. A plurality of rotating grooves are coaxially and horizontally formed in the multi-layer die head. The extrusion flow channel is communicated with the feed inlet through the rotating groove. The rotating ring is rotatably installed in the rotating groove. A plurality of blades are annularly and evenly distributed on the inner wall of the rotating ring.

[0009] When the cleaning agent comes into the rotating groove and flows towards the extrusion flow channel, during the process, the power of the cleaning agent is converted into the rotational motion of the rotating ring under the action of the blades, driving the rotating ring to rotate. By utilizing the fluid kinetic energy during the cleaning process of the cleaning agent to drive the rotating ring to rotate, compared with the traditional electrically or pneumatically driven rotating ring, there is no need to consume a large amount of additional electrical energy or compressed air and other energy sources, reducing the cost of the cleaning equipment.

[0010] Preferably, a chute is formed in the swivel ring, the direction of the chute points to the axis of the swivel ring, a slider is slidably installed in the chute, the rotating groove communicates with the extrusion channel through the chute, the slider is connected to the scraper, one side of the slider away from the axis of the swivel ring is connected to the swivel ring through a first spring, mounting grooves are formed in the outer walls of the inner die and the central die, the scraper is installed in cooperation with the mounting grooves, and the side of the scraper away from the axis of the multi-layer die head is consistent with the shapes of the outer walls of the inner die and the central die. When the scraper is located in the mounting groove, the slider blocks the communication between the rotating groove and the extrusion channel through the chute.

[0011] When the cleaning agent does not reach the rotating groove, under the action of the first spring, the scraper is located in the mounting groove. Through the action of the first spring, the scraper is in the mounting groove, avoiding the scraper being in the extrusion channel during the production process, which affects the flow of the material and the uniformity of the material extrusion. At the same time, the block blocks the communication between the rotating groove and the extrusion channel through the chute, preventing the material from flowing into the rotating groove and avoiding accumulation in the rotating groove, which hinders the normal operation of the cleaning equipment. When the cleaning agent reaches the rotating groove, since the position of the slider blocks the flow of the cleaning agent to the extrusion channel, the cleaning agent first acts on the slider. Under the pressure of the cleaning agent, the slider is pushed to slide, and then the scraper is driven into the extrusion channel. This process does not require manual intervention and saves the time of manual operation.

[0012] Preferably, the scraper includes a first blade part and a second blade part. The second blade part is connected to the slider. The first blade part is slidably installed in the second blade part. The two sides of the second blade part coincide with the two sides of the first blade part. A guide groove is formed in the side wall of the chute. The guide groove is inclined. The highest point of the guide groove is close to the axis of the multi-layer die head. A convex platform is provided on the side wall of the first blade part. The convex platform penetrates the slider and is slidably connected with the guide groove. Thread groove openings are provided on the side walls of the first blade part and the second blade part away from the axis of the swivel ring. When the scraper is located in the mounting groove, the thread groove openings are matched with the spiral grooves.

[0013] By providing thread groove openings on the side walls of the first blade part and the second blade part away from the axis of the swivel ring, it is avoided that the scraper hinders the smooth flow of the material in the spiral groove. Due to the existence of the thread groove openings, when the extrusion channel in the die head is in contact, there is a cleaning dead angle in the area corresponding to the thread groove openings, and impurities will still remain. In the design, when the cleaning agent drives the scraper into the extrusion channel, at the same time, the convex platform on the first blade part slides along the inclined guide groove, prompting the relative sliding of the first blade part and the second blade part, and then compensating for the thread groove openings on the side. Through this design, using the cleaning agent as the power source, while driving the scraper into the extrusion channel, the convex platform on the first blade part slides along the inclined guide groove, prompting the dislocation of the first blade part and the second blade part, and compensating for the thread groove openings on the side, avoiding the problem of cleaning dead angles when the thread groove opening structure on the scraper contacts the inner wall of the die head, and ensuring that the scraper can clean the inner wall of the die head comprehensively during the cleaning process.

[0014] Preferably, a clamping groove is formed in the sliding groove, and the first blade portion penetrates through the slider. When the boss is at the lowest point of the guide groove, the first blade portion cooperates with the clamping groove.

[0015] When the boss is at the lowest point of the guide groove, the first blade portion is in close cooperation with the clamping groove, thereby restricting and jamming the slider, avoiding the slider from moving due to factors such as centrifugal force, material impact or mechanical vibration when the swivel ring drives the scraper to rotate and clean, and then driving the scraper to generate friction and collision with the inner wall of the extrusion channel. This not only damages the blade portion of the scraper, shortens its service life, but also scratches the inner wall of the die head, affecting the accuracy and sealing performance of the die head, ensuring the extension of the service life of the multi-layer die head and the scraper, and reducing the equipment maintenance cost of the enterprise.

[0016] Preferably, a scraping block is slidably installed on one side of the first blade portion close to the axis of the swivel ring. The installation groove coincides with the end of the spiral groove near the extrusion port. The sliding direction of the scraping block is parallel to the axis of the swivel ring. The scraping block includes an extrusion portion and a scraping portion. The extrusion portion is located on the side of the scraping portion away from the axis of the swivel ring. The extrusion portion is made of an elastic material. The end face of the scraping portion is connected to the first blade portion through a second spring. When the first blade portion is in the clamping groove, the side wall of the scraping portion cooperates with the spiral groove.

[0017] Due to the structural limitations of the scraper and the spiral setting of the spiral groove, it is difficult for the scraper to penetrate into the recesses of the spiral groove, resulting in residual impurities and affecting the cleaning effect. When the scraper moves into the extrusion channel, through the cooperation of the scraping block and the spiral groove, at this time, the swivel ring rotates to drive the scraper and then drive the scraping block to scrape the impurities in the spiral groove, avoiding the appearance of residual impurities in the spiral groove and improving the cleaning effect. At the same time, due to the unique structural design of the spiral groove, that is, the depth of the horizontal cross-section decreases along the axis towards the extrusion port direction. During the cleaning process of the scraping block, the extrusion portion, with its good deformation ability, flexibly changes its shape according to the change of the radial dimension of the spiral groove, ensuring that the scraping portion always closely fits the groove wall, ensuring that the scraping block comprehensively cleans the spiral groove during the cleaning process. When the scraping block reaches the connection between the installation groove and the end of the spiral groove near the extrusion port during the cleaning of the spiral groove, the elastic potential energy of the extrusion portion is released to push the scraping block into the installation groove, and at the same time, the elastic potential energy of the second spring is released, causing the scraping block to slide in the installation groove, and then return to the initial position to prepare for the next cleaning, thereby ensuring the continuity of equipment cleaning.

[0018] Preferably, the outer side walls on both sides of the second blade portion are inclined, the scraper is inclined, and the inclination direction of the scraper is the same as the inclination direction of the blade.

[0019] The outer wall of the second blade part is inclined. When the scraper moves along with the slider, the contact between the blade part and the inner wall of the extrusion channel, compared with scraping with a vertical blade, the inclined blade can better fit the inner wall of the channel during scraping. During the forward process, it can more smoothly cut into the impurity layer attached to the wall of the extrusion channel. Whether it is granular impurities and sand grains mixed in the material, or relatively viscous material residues, they can all be more effectively peeled off the channel wall, greatly improving the removal rate of impurities by a single scraping, and thus improving the cleaning effect of the scraper on the impurities on the wall of the extrusion channel.

[0020] At the same time, the inclined setting of the scraper can guide the scraped impurities towards the extrusion port direction, which is beneficial to the discharge of impurities, avoiding the circulation and sedimentation of impurities in the extrusion channel, ensuring the cleaning effect in the extrusion channel. At the same time, the inclined direction of the scraper is the same as the inclined direction of the blade, converting the power of the cleaning agent in the extrusion channel into the power to drive the rotation of the scraper, realizing the efficient utilization of energy, enabling the scraper to have a more sufficient power source during operation, and being able to ensure that the scraper scrapes the stubborn impurities attached to the wall of the extrusion channel.

[0021] Preferably, a plurality of convex rings are evenly distributed on the outer wall of the rotating ring. The cross-section of the convex ring is triangular, and the convex rings are longitudinally arranged.

[0022] Through the setting of the convex rings on the outer wall of the rotating ring, the contact between the rotating ring and the multi-layer die head changes from the original possible planar contact to local contact at the vertices of the convex rings, reducing the contact area between the outer wall of the rotating ring and the tank body. The reduction of the contact area directly reduces the friction between the rotating ring and the multi-layer die head. A smaller friction means less resistance on the rotating ring. At the same time, the contact area can reduce the wear degree between the rotating ring and the multi-layer die head. With less resistance on the rotating ring, the energy required for the rotation of the rotating ring will also be reduced, which means that less energy can be used to maintain the rotation of the rotating ring, improving the energy utilization efficiency. At the same time, in the traditional planar contact mode, the large-area friction between the rotating ring and the multi-layer die head will cause faster wear of the components. However, through the local contact mode of the convex rings, the friction is reduced, and the wear part of the rotating ring is mainly concentrated at the vertices of the convex rings, and the wear degree is relatively light. This effectively extends the service life of the rotating ring, reduces the frequency of equipment maintenance and component replacement, and reduces the equipment maintenance cost of the enterprise.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. Through the cooperation of the scraper, the swivel ring, and the scraper block drive assembly, the present invention converts the power of the cleaning agent into the moving power of the scraper and the swivel ring through the drive assembly. Thereby, the scraper scrapes and cleans the impurities and waste materials in the extrusion channel, avoiding the safety risks associated with manual disassembly and assembly. Secondly, the design of the first cutting edge and the second cutting edge on the scraper avoids cleaning dead corners through dislocation. At the same time, the scraper block can penetrate into the spiral groove to clean impurities and can adapt to size changes, ensuring thorough cleaning. Furthermore, it ensures the thorough cleaning of impurities in the multi-layer die head, avoiding manual disassembly and cleaning, reducing labor costs, and improving the efficiency of the entire extrusion molding operation.

[0025] 2. Through the design of the slider and the drive assembly, the present invention utilizes the fluid kinetic energy during the cleaning with the cleaning agent. It first acts on the slider, pushing the slider to slide, and then driving the scraper into the extrusion channel. At the same time, the cleaning agent can enter the extrusion channel through the chute. During this process, the blades convert the kinetic energy of the cleaning agent into the rotational movement of the swivel ring. Compared with the traditional electrically or pneumatically driven swivel ring, it does not require additional consumption of a large amount of energy such as electric energy or compressed air, achieving a significant cost savings in terms of energy.

[0026] 3. Through the setting of the scraper, the inclination angle and the side wall of the scraper help to guide the scraped impurities towards the extrusion port for discharge, avoiding the circulation and settlement of impurities in the extrusion channel and ensuring the cleaning effect. At the same time, the inclination direction is the same as that of the blades, converting the power of the cleaning agent flowing in the extrusion channel into the rotational power of the scraper, achieving efficient energy utilization, enhancing the ability to scrape stubborn impurities. At the same time, the specific inclination angle of the outer side wall of the second cutting edge can optimize the scraping effect, effectively peel off various impurities, improve the impurity removal rate of a single scraping, and improve the cleaning effect of the multi-layer die head. Description of the Drawings

[0027] Figure 1 Schematic diagram of the overall structure of the film hot melt extruder for packaging bag film production;

[0028] Figure 2 Axonometric sectional view of the multi-layer die head in the present invention;

[0029] Figure 3 Cross-sectional view of the multi-layer die head in the present invention;

[0030] Figure 4 In the present invention Figure 3 Partial enlarged view of location A;

[0031] Figure 5 Assembly drawing of the drive assembly and the scraper in the present invention;

[0032] Figure 6 In the present invention Figure 5 Partial enlarged view of location B;

[0033] Figure 7 For the present invention Figure 5 Partial enlarged view at C in the present invention;

[0034] Figure 8 Axonometric sectional view of the scraper and slider assembly in the present invention.

[0035] In the figure: 1, frame; 12, material pipe; 13, extrusion device; 14, extrusion channel; 15, feed inlet; 16, extrusion outlet; 2, multi-layer die head; 21, outer die; 22, inner die; 23, center die; 24, spiral groove; 241, spiral groove opening; 25, first spring; 26, installation groove; 3, rotating ring; 31, convex ring; 32, guide groove; 33, clamping groove; 34, blade; 35, sliding groove; 36, slider; 4, scraper; 41, first cutting edge; 411, convex platform; 42, second cutting edge; 43, scraping block; 44, extrusion part; 45, cleaning and scraping part; 46, second spring; 5, rotating groove. Specific embodiments

[0036] Please refer to Figures 1 to 8 , the present invention provides a film hot-melt extruder for producing packaging bag films, and the technical solution is as follows:

[0037] A film hot-melt extruder for producing packaging bag films, comprising an extrusion device 13, a multi-layer die head 2, an outer die 21, an inner die 22, a central die 23, a rotating ring 3 and a scraper 4. The multi-layer die head 2 is installed on a frame 1. The multi-layer die head 2 includes an outer die 21, an inner die 22 and a central die 23. The outer walls of the inner die 22 and the central die 23 are provided with spiral grooves 24. The outer die 21, the inner die 22 and the central die 23 are coaxially installed from outside to inside. The adjacent side walls of the outer die 21, the inner die 22 and the central die 23 form an extrusion flow channel 14. The multi-layer die head 2 is provided with a feed inlet 15 and an extrusion outlet 16. The extrusion flow channel 14 is respectively communicated with the feed inlet 15 and the extrusion outlet 16. The feed inlet 15 is connected to the extrusion device 13 through a material pipe 12. The connection part between the feed inlet 15 and the extrusion flow channel 14 is located in the spiral groove 24. The depth of the horizontal section of the spiral groove 24 decreases along the axis towards the extrusion outlet 16. When the machine is running, the material enters the extrusion device 13 for heating treatment and is transmitted through the material pipe 12 to the feed inlet 15 of the multi-layer die head 2 connected thereto. At this time, the material is controlled to flow from the feed inlet 15 into the spiral groove 24 and then reach the extrusion flow channel 14. The extrusion flow channel 14 finally converges with the extrusion outlet 16. Different materials are stacked and extruded at the extrusion outlet 16, and finally a bagged film for packaging is obtained. A plurality of rotating rings 3 are coaxially and horizontally rotatably installed in the multi-layer die head 2. A plurality of scrapers 4 are installed on the rotating rings 3. The scrapers 4 are located in the extrusion flow channel 14, and the cross-sectional width of the scraper 4 is equal to the cross-sectional width of the extrusion flow channel 14. A driving component is arranged in the multi-layer die head 2. The driving component is connected to the rotating ring 3. The driving component drives the rotating ring 3 to drive the scraper 4 to rotate around the axis with the power of the cleaning agent injected into the feed inlet 15. By driving the rotating ring 3 to rotate through the driving component, the scraper 4 is driven to scrape the impurities accumulated in the multi-layer die head 2, avoiding the problem of the increased labor cost caused by manual disassembly and cleaning and the impact on the efficiency of the entire extrusion molding operation.

[0038] Please refer to Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7, the driving component includes blades 34. A plurality of rotating grooves 5 are horizontally and coaxially formed in the multi-layer die head 2. The extrusion flow channel 14 communicates with the feed port 15 through the rotating grooves 5. The rotating ring 3 is rotatably installed in the rotating grooves 5. A plurality of blades 34 are evenly distributed in a ring shape on the inner wall of the rotating ring 3. When the cleaning agent enters the rotating groove 5 and flows towards the extrusion flow channel 14, during this process, the power of the cleaning agent is converted into the rotational motion of the rotating ring 3 under the action of the blades 34, driving the rotation of the rotating ring 3. By utilizing the fluid kinetic energy during the cleaning process of the cleaning agent to drive the rotation of the rotating ring 3, compared with the traditional rotating ring 3 driven by electricity or pneumatic, it does not require additional consumption of a large amount of energy such as electric energy or compressed air, reducing the cost of the cleaning equipment; a sliding groove 35 is formed on the rotating ring 3, and the direction of the sliding groove 35 points to the axis of the rotating ring 3. A slider 36 is slidably installed in the sliding groove 35. The rotating groove 5 communicates with the extrusion flow channel 14 through the sliding groove 35. The slider 36 is connected to the scraper 4. One side of the slider 36 away from the axis of the rotating ring 3 is connected to the rotating ring 3 through a first spring 25. Installation grooves 26 are formed on the outer walls of the inner die 22 and the central die 23. The scraper 4 is installed in cooperation with the installation grooves 26. Under the action of the first spring 25, the scraper 4 is located in the installation grooves 26. Through the action of the first spring 25, the scraper 4 is in the installation grooves 26, avoiding the scraper 4 being in the extrusion flow channel 14 during the production process and affecting the flow of materials. The side of the scraper 4 away from the axis of the multi-layer die head 2 has the same shape as the outer walls of the inner die 22 and the central die 23. When the scraper 4 is located in the installation grooves 26, the slider 36 blocks the communication between the rotating groove 5 and the extrusion flow channel 14 through the sliding groove 35. When the cleaning agent enters the rotating groove 5, due to the position of the slider 36 blocking the cleaning agent from flowing towards the extrusion flow channel 14, the cleaning agent first acts on the slider 36. Under the pressure of the cleaning agent, the slider 36 is pushed to slide, and then the scraper 4 is driven to enter the extrusion flow channel 14. This process does not require manual intervention, improving the overall cleaning efficiency; the scraper 4 includes a first cutting edge 41 and a second cutting edge 42. The second cutting edge 42 is connected to the slider 36. The first cutting edge 41 is slidably installed in the second cutting edge 42. The two sides of the second cutting edge 42 coincide with the two sides of the first cutting edge 41. A guide groove 32 is formed on the side wall of the sliding groove 35. The guide groove 32 is inclined. The highest point of the guide groove 32 is close to the axis of the multi-layer die head 2. A convex platform 411 is provided on the side wall of the first cutting edge 41. The convex platform 411 penetrates through the slider 36 and is slidably connected to the guide groove 32. Threaded groove openings 241 are provided on the side walls of the first cutting edge 41 and the second cutting edge 42 away from the axis of the rotating ring 3. When the scraper 4 is located in the installation grooves 26, the threaded groove openings 241 are matched with the spiral grooves 24. When the scraper 4 moves to the extrusion flow channel, the convex platform 411 on the first cutting edge 41 moves from the highest point of the guide groove 32 to the lowest point of the guide groove 32. During this process, the first cutting edge 41 and the second cutting edge 42 slide relative to each other, causing the first cutting edge 41 and the second cutting edge 42 to be misaligned, compensating for the threaded groove openings 241 on the side of the scraper 4, and avoiding the problem of cleaning dead corners when the threaded groove openings 241 on the scraper 4 contact the inner wall of the multi-layer die head 2;A clamping groove 33 is formed in the sliding groove 35, and the first cutting edge 41 penetrates through the sliding block 36. When the boss 411 is located at the lowest point of the guide groove 32, the second cutting edge 42 cooperates with the clamping groove 33 to restrict and lock the sliding block 36, so as to avoid when the rotary ring 3 drives the scraper 4 to rotate for cleaning; A plurality of convex rings 31 are evenly arranged on the outer wall of the rotary ring 3. The cross-section of the convex ring 31 is triangular, and the convex ring 31 is longitudinally arranged. Through the arrangement of the convex rings 31 on the outer wall of the rotary ring 3, the contact between the rotary ring 3 and the multi-layer die head 2 changes from the original possible plane contact to local contact with the vertex of the convex ring 31. Furthermore, the resistance received by the rotary ring 3 is reduced, and the energy required for the rotary ring 3 to rotate will also be reduced, improving the energy utilization efficiency; The outer side walls on both sides of the second cutting edge 42 are inclined, the scraper 4 is inclined, and the inclination direction of the scraper 4 is the same as the inclination direction of the blade 34. The inclined setting of the scraper 4 can guide the scraped impurities towards the extrusion port, which is beneficial to the discharge of impurities, avoiding the circulation and settlement of impurities in the extrusion channel 14, ensuring the cleaning effect in the extrusion channel 14. At the same time, since the inclination direction of the scraper 4 is the same as the inclination direction of the blade 34, the power of the cleaning agent in the extrusion channel 14 is converted into the power for driving the scraper 4 to rotate, realizing the efficient utilization of energy.

[0039] Please refer to Figure 5 、 Figure 6, a scraping block 43 is slidably installed on one side of the first blade part 41 close to the axis of the rotating ring 3. The scraping block 43 is flush with the spiral groove 24 in the horizontal direction near the end of the feed port 15. Installation grooves 26 are provided on the inner die 22 and the central die 23. A scraping knife 4 is slidably installed in the installation groove 26. The installation groove 26 coincides with the spiral groove 24 near the end of the extrusion port 16. The sliding direction of the scraping block 43 is parallel to the axis of the rotating ring 3. The scraping block 43 includes an extrusion part 44 and a scraping part 45. The extrusion part 44 is located on the side of the scraping part 45 away from the axis of the rotating ring 3. The extrusion part 44 is made of an elastic material. The upper end surface of the scraping part 45 is connected to the first blade part 41 through a second spring 46. When the first blade part 41 is located in the clamping groove 33, the side wall of the scraping part 45 cooperates with the spiral groove 24. By the cooperation of the scraping block 43 and the spiral groove 24, at this time, the rotation of the rotating ring 3 drives the scraping knife 4 and then drives the scraping block 43 to scrape the impurities in the spiral groove 24, avoiding the residue of impurities in the spiral groove 24. At the same time, since the extrusion part 44 is made of rubber, it has excellent resilience. With its good deformation ability, it flexibly changes its shape according to the change of the radial dimension of the spiral groove 24, ensuring that the scraping part 45 always fits tightly against the groove wall, guaranteeing that the scraping block 43 comprehensively cleans the spiral groove 24 during the cleaning process. At the same time, the setting that the installation groove 26 is connected to the spiral groove 24 near the end of the extrusion port 16. When the scraping block 43 reaches the connection between the installation groove 26 and the spiral groove 24 near the end of the extrusion port 16 during the cleaning of the spiral groove 24, the elastic potential energy of the extrusion part 44 is released to push the cleaning block 43 into the installation groove 26. At the same time, the elastic potential energy of the second spring 46 is released, making the scraping block 43 slide in the installation groove 26, and then returning to the initial position to prepare for the next cleaning, thereby ensuring the continuity of the equipment cleaning.

[0040] Working principle: When cleaning the impurities in the multi-layer die head 2, the cleaning agent is introduced into the feed port 15. At this time, the cleaning agent is controlled to enter the rotating ring. At this time, due to the position of the slider 36 blocking the flow of the cleaning agent to the extrusion channel 14, the cleaning agent first acts on the slider 36. Under the action of the cleaning agent pressure, the slider 36 is pushed to slide, thereby driving the scraper 4 into the extrusion channel 14. During the movement of the scraper 4, due to the sliding fit between the convex platform 411 and the guide groove 32 and the inclined setting, under the action of the convex platform 411 and the guide groove 32, the first cutting edge 41 and the second cutting edge 42 slide relative to each other. At this time, the first cutting edge 41 and the second cutting edge 42 are misaligned, thereby compensating for the side screw groove opening 241, so that the scraper 4 fully covers the inner wall of the die head. When the convex platform 411 is at the lowest point of the guide groove 32, the first cutting edge 41 is tightly fitted with the clamping groove 33, thereby restricting and locking the slider 36. When the scraper 4 comes from the extrusion channel 14, at this time, the scraping block 43 cooperates with the spiral groove 24. At this time, the rotating groove flows to the extrusion channel 14 through the sliding groove 35. During the process, the cleaning agent acts on the blade 34. Under the action of the blade 34, the kinetic energy of the cleaning agent is converted into the rotational movement of the rotating ring 3, thereby driving the scraper 4 to rotate. At this time, the rotation of the rotating ring 3 drives the scraper 4 and then drives the scraping block 43 to scrape the impurities in the spiral groove 24, avoiding impurity residue in the spiral groove 24 and improving the cleaning effect. Due to the unique structural design of the spiral groove 24, that is, the depth of the horizontal cross-section decreases along the axis direction towards the extrusion port 16. During the cleaning process of the scraping block 43, the extrusion part 44 can flexibly change its shape according to the change of the radial dimension of the spiral groove 24 by virtue of its deformation ability, ensuring that the cleaning part 45 always closely adheres to the groove wall. When the scraping block 43 cleans the spiral groove 24 and the scraper 4 reaches the connection between the installation groove 26 and the end of the spiral groove 24 near the extrusion port 16, the elastic potential energy of the extrusion part 44 is released to push the cleaning block 43 into the installation groove 26. At the same time, the elastic potential energy of the second spring 46 is released, so that the scraping block 43 slides in the installation groove 26 and then returns to the initial position to prepare for the next cleaning. At this time, the injection of the cleaning agent can be stopped. At the same time, the first spring 25 pushes the slider 36 to reset, thereby driving the scraper 4 back into the installation groove 26, and at the same time pushing the second cutting edge 42 to reset to prepare for the next production. After the cleaning agent removes the impurities and waste in the multi-layer die head 2, the residual cleaning agent in the multi-layer die head can be cleaned by introducing high-pressure air through the feed port 15, and the multi-layer die head 2 can be dried.

[0041] The above has described in detail a specific embodiment of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the above-described embodiment. For those skilled in the art, without departing from the principles and ideas of the present invention, various changes, modifications, substitutions, and variations made to these embodiments should still fall within the protection scope of the present invention.

Claims

1. A film hot melt extruder for producing packaging bag films, characterized in that: The invention comprises an extrusion device (13), a multi-layer die head (2), an outer die (21), an inner die (22), a center die (23), a rotating ring (3) and a scraper (4); the multi-layer die head (2) is installed on the frame (1); the multi-layer die head (2) comprises an outer die (21), an inner die (22) and a center die (23); the outer walls of the inner die (22) and the center die (23) are provided with a spiral groove (24); the outer die (21), the inner die (22) and the center die (23) are coaxially installed from outside to inside; the adjacent side walls of the outer die (21), the inner die (22) and the center die (23) form an extrusion flow channel (14); the multi-layer die head (2) is provided with a feed port (15) and an extrusion port (16); the extrusion flow channel (14) is connected to the feed port (15) and the extrusion port (16) respectively. The feed port (15) is connected to the extrusion device (13) through the material pipe (12); the connection between the feed port (15) and the extrusion flow channel (14) is located in the spiral groove (24); the horizontal cross-sectional depth of the spiral groove (24) decreases along the axis toward the extrusion port (16); a plurality of rotating rings (3) are coaxially and horizontally mounted in the multi-layer die head (2); a plurality of scrapers (4) are mounted on the rotating ring (3); the scrapers (4) are located in the extrusion flow channel (14); and the cross-sectional width of the scrapers (4) is equal to the cross-sectional width of the extrusion flow channel (14); a driving component is arranged in the multi-layer die head (2); the driving component is connected to the rotating ring (3); the driving component drives the rotating ring (3) with the power of the cleaning agent injected from the feed port (15) to drive the scrapers (4) to rotate around the axis.

2. A film hot melt extruder for producing packaging bag film according to claim 1, characterized in that: The driving assembly comprises blades (34), a plurality of rotating grooves (5) are coaxially and horizontally provided in the multi-layer die head (2), the extrusion flow channel (14) is connected with the feed port (15) through the rotating grooves (5), the rotating ring (3) is rotatably installed in the rotating grooves (5), and a plurality of blades (34) are evenly distributed in an annular shape on the inner wall of the rotating ring (3).

3. A film hot melt extruder for producing packaging bag film according to claim 2, characterized in that: The rotating ring (3) is provided with a slide groove (35), the direction of the slide groove (35) points to the axis of the rotating ring (3), a slider (36) is slidably installed in the slide groove (35), the rotating groove (5) is connected to the extrusion flow channel (14) through the slide groove (35), the slider (36) is connected to the scraper (4), the side of the slider (36) away from the axis of the rotating ring (3) is connected to the rotating ring (3) through a No. 1 spring (25), the outer walls of the inner mold (22) and the center mold (23) are provided with a mounting groove (26), the scraper (4) is installed in cooperation with the mounting groove (26), the side of the scraper (4) away from the axis of the multi-layer die head (2) is consistent in shape with the outer walls of the inner mold (22) and the center mold (23), when the scraper (4) is located in the mounting groove (26), the slider (36) blocks the rotating groove (5) from being connected to the extrusion flow channel (14) through the slide groove (35).

4. A film hot melt extruder for producing packaging bag film according to claim 3, characterized in that: The scraper (4) comprises a first blade portion (41) and a second blade portion (42), wherein the second blade portion (42) is connected to the slider (36), the first blade portion (41) is slidably mounted in the second blade portion (42), the two sides of the second blade portion (42) overlap with the two sides of the first blade portion (41), a guide groove (32) is provided on the side wall of the slide groove (35), the guide groove (32) is inclined, the highest point of the guide groove (32) is close to the axis of the multi-layer die head (2), a boss (411) is provided on the side wall of the first blade portion (41), the boss (411) passes through the slider (36) and is slidably connected to the guide groove (32), a screw groove opening (241) is provided on the side wall of the first blade portion (41) and the second blade portion (42) away from the axis of the rotating ring (3), and when the scraper (4) is located in the mounting groove (26), the screw groove opening (241) matches the spiral groove (24).

5. A film hot melt extruder for producing packaging bag film according to claim 4, characterized in that: A clamping groove (33) is provided in the slide groove (35), and the first blade portion (41) passes through the slider (36). When the boss (411) is located at the lowest point of the guide groove (32), the first blade portion (41) cooperates with the clamping groove (33).

6. A film hot melt extruder for producing packaging bag film according to claim 5, characterized in that: A scraper block (43) is slidably mounted on one side of the first blade portion (41) close to the axis of the rotating ring (3); the mounting groove (26) overlaps with the end of the spiral groove (24) close to the extrusion port (16); the sliding direction of the scraper block (43) is parallel to the axis of the rotating ring (3); the scraper block (43) comprises an extrusion portion (44) and a scraping portion (45); the extrusion portion (44) is located on the side of the scraping portion (45) away from the axis of the rotating ring (3); the extrusion portion (44) is made of elastic material; the end surface of the scraping portion (45) is connected to the first blade portion (41) via a No. 2 spring (46); when the first blade portion (41) is located in the guide groove (33), the side wall of the scraping portion (45) cooperates with the spiral groove (24).

7. A film hot melt extruder for producing packaging bag film according to claim 5, characterized in that: The outer side walls on both sides of the second blade portion (42) are arranged inclined, the scraper (4) is arranged inclined, and the inclination direction of the scraper (4) is the same as the inclination direction of the blade (34).

8. A film hot melt extruder for producing packaging bag film according to claim 4, characterized in that: A plurality of convex rings (31) are evenly distributed on the outer wall of the rotating ring (3), the cross section of the convex rings (31) is triangular, and the convex rings (31) are arranged longitudinally.

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