Feeding mechanism of plastic film blowing machine and using method of feeding mechanism

Abstract

The invention relates to the technical field of plastic feeding, in particular to a feeding mechanism of a plastic film blowing machine and a using method thereof.The feeding mechanism comprises a vacuum hopper, a first magnet and a cleaning box, a through-flow cavity, a feeding nozzle and a discharging opening are formed in the cleaning box, the feeding nozzle and the discharging opening communicate with the side walls of the two sides of the through-flow cavity correspondingly, and the feeding nozzle is located on the upper side of the discharging opening; a through-flow cavity is formed in the bottom of the feeding nozzle, a collecting groove is formed in the bottom of the through-flow cavity, a connecting channel is arranged between the feeding nozzle and the through-flow cavity, and the first magnet is arranged on the side wall of the connecting channel. And part of the metal scraps deflect towards the lower collecting tank and fall into the collecting tank, so that the problem that the metal scraps in the plastic raw materials enter the blow molding machine, the surface of a blown film is unsmooth and is provided with spot bulges and torn, and the physical property of the film is reduced is solved, and the film forming quality is ensured.

Description

TECHNICAL FIELD

[0001] The application relates to a plastic feeding mechanism and a method thereof. BACKGROUND

[0002] The feeding mechanism is a device responsible for transporting plastic raw materials from a storage location to the feeding port of a plastic film blowing machine during the production process of the plastic film blowing machine. The feeding mechanism of the plastic film blowing machine includes a gravity feeding mechanism, a screw feeding mechanism, and a vacuum feeding mechanism. The vacuum feeding mechanism uses a vacuum pump to generate negative pressure, sucks raw materials through a suction nozzle, and sends them to a storage tank through a conveying pipeline, and then supplies them to the film blowing machine as needed. The vacuum feeding mechanism has the advantages of large transportation flow and high automation degree.

[0003] During the production of ground cover film, greenhouse film, and garbage bag film, recycled plastic products are used for production. The recycled plastic products can reduce production costs to a certain extent. The feeding mechanism transports plastic raw materials into the film blowing machine to produce a film. However, metal objects are mixed in the initially recycled materials. The equipment is not completely separated by magnetic separation during the recycling process, so that the recycled materials contain metal debris. The metal debris in the recycled materials can cause the film blown by the blow molding machine to have a rough surface with spots and protrusions, and can cause the film to be torn and stretched, thereby reducing the physical properties of the film. For this problem, the prior art provides a solution, such as the invention patent with the patent application number CN202210165045.9, which provides an iron-containing impurity removal device for an extruder. The patent provides a technical solution as follows: an iron-containing impurity removal device for an extruder is provided on the inner wall of the feeding barrel. The small magnetic bodies are arranged in multiple rows to increase the contact opportunities between the magnetic bodies and the materials and enhance the iron removal effect. On the other hand, the side surface area of the magnetic block, which is different from or opposite to the flow direction of the materials, is also significantly increased, which is beneficial to adsorb and accumulate iron-containing impurities and avoid the iron-containing impurities from being mixed into the flow of materials under the impact of the flow of materials. In the above-mentioned solution, a feeding auger is arranged in the feeding barrel, which can prevent the materials from being blocked. However, the materials are stirred in the feeding auger, which prolongs the residence time of the materials in the feeding barrel, slows down the feeding speed, and cannot meet the demand for rapid feeding on a high-speed production line, thereby failing to adapt to the vacuum feeding mechanism. In addition, as the use time increases, the iron filings attached to the surface of the magnetic body increase, and the thickness of the iron filings increases, which can shield the magnetic field of the magnetic body to a certain extent, thereby reducing the attraction of the magnetic body to the iron-containing impurities in the materials, resulting in poor iron removal effect. SUMMARY

[0004] The application aims to provide a feeding mechanism of a plastic film blowing machine and a use method thereof, so as to solve the problem that metal scraps in the material cannot be removed in time when the vacuum feeding mechanism is used for feeding, so that the material with the metal scraps enters the film blowing machine, and the film blown by the film blowing machine has uneven surface with spots and protrusions, is stretched and torn, and the physical properties of the film are reduced.

[0005] To achieve the above object, the application provides the following technical scheme.

[0006] A feeding mechanism of a plastic film blowing machine and a use method thereof, comprising a vacuum hopper, a vacuum generator, a first magnet and a cleaning box, a through-flow cavity, a feeding nozzle and a discharging port are arranged in the cleaning box, the feeding nozzle and the discharging port are respectively communicated with the side walls on the two sides of the through-flow cavity, the feeding nozzle is located on the upper side of the discharging port, the discharging port is communicated with the inner side of the vacuum hopper, the vacuum hopper is communicated with the vacuum generator, a collecting groove is arranged on the bottom of the through-flow cavity, the collecting groove is located on the side away from the discharging port, a scrap iron box is arranged on the bottom of the collecting groove, a connecting channel is arranged between the feeding nozzle and the through-flow cavity, the connecting channel is horizontally arranged, the first magnet is arranged on the side wall of the connecting channel, and the width of the first magnet is equal to the width of the top wall of the connecting channel.

[0007] When feeding the blow molding machine, connect the vacuum hopper to the machine's feed inlet and the feed nozzle to the material conveying pipe. Start the vacuum generator to remove air from the vacuum hopper, creating a negative pressure environment. External gas enters the vacuum hopper through the conveying pipe, feed nozzle, connecting channel, flow chamber, and discharge port. During this process, the airflow carries the plastic material forward. When the plastic material reaches the connecting channel, some metal debris is attracted to the surface of magnet number one under its magnetic force. Under the influence of the airflow, the plastic material and some metal debris continue forward in the connecting channel. When they reach the flow chamber, the metal debris that was not attracted by magnet number one moves along the airflow direction. Simultaneously, due to the higher density and mass of the metal debris, it deflects downwards towards the collection trough under gravity. The deflected metal debris falls into the collection trough and then into the scrap box. Meanwhile, due to the plastic material... Unaffected by the magnetic field of magnet number one, the material continues to move along the airflow direction. During this process, because the density of the plastic material is lower than that of the metal fragments, its mass is lower and it is less affected by gravity. At this point, the plastic material and the metal fragments are at the same height. Under the action of the airflow, the displacement of the plastic material in the horizontal direction is greater than that of the metal fragments, allowing the plastic material to reach the outlet and enter the vacuum hopper. Through the design of magnet number one, the metal fragments in the plastic material are adsorbed. At the same time, the design of the collection tank takes advantage of the higher density and mass of the metal fragments. Under the action of gravity, the metal fragments that are not adsorbed are deflected towards the collection tank below and fall into the collection tank. This achieves the removal and collection of metal fragments contained in the plastic material, preventing metal fragments from being carried into the blow molding machine and causing problems such as uneven surface, spots, bulges, stretching and tearing of the blown film, which would reduce the physical properties of the film and thus ensure the quality of the film formation.

[0008] Preferably, the first magnet is located on the top wall of the connecting channel, and the lower end face of the first magnet is flush with the top wall of the connecting channel. Multiple baffles are evenly distributed on the lower end face of the first magnet. An inclined surface is provided on the side wall of the baffle away from the flow cavity. The feed nozzle is set at an angle to the connecting channel, and the axial direction of the feed nozzle is perpendicular to the inclined surface. The projected area of ​​the feed nozzle along the axial direction is S1. The projection of the multiple inclined surfaces in the axial direction of the feed nozzle is a complete projection surface, and the projected area is S2, wherein S1≤S2.

[0009] When the plastic raw material enters the connecting channel, the moving plastic raw material collides perpendicularly with the first inclined surface on the baffle. The impact and reaction forces generated by the perpendicular collision with the first inclined surface disperse the clumps of plastic raw material. At the same time, the impact and vibration can break the adhesion between the metal fragments and the surface of the plastic raw material, causing the small metal fragments originally attached to the surface of the plastic raw material to fall off. At this time, the metal fragments are attracted to the surface of the support plate under the magnetic force of the first magnet. By setting the first inclined surface on the baffle, and the axis of the feed nozzle is perpendicular to the first inclined surface, the plastic raw material collides perpendicularly with the first inclined surface, dispersing the clumps of plastic raw material and shaking off the metal fragments on the surface of the plastic raw material through the impact. This avoids the plastic raw material from clumping together, which would prevent the metal fragments inside the clumps from being cleaned. It also prevents the metal fragments from adhering to the surface of the plastic raw material, causing the plastic raw material to carry metal fragments into the blow molding machine, resulting in problems such as uneven surface, spots, bulges, stretching and tearing of the blown film, and thus degrading the physical properties of the film. This ensures the quality of the film formation.

[0010] Furthermore, by setting the complete projection surface S2 of multiple inclined surfaces in the axial direction of the feed nozzle to be greater than or equal to the projection area S1 of the feed nozzle along the axial direction, the plastic material in the feed nozzle can be completely impacted perpendicularly onto the inclined surfaces. This prevents the plastic material from being missed and failing to impact the inclined surfaces perpendicularly, thus avoiding the inability to clean the metal debris inside the agglomerated plastic material. At the same time, the metal debris on the surface of the plastic material cannot be shaken off, causing the plastic material to carry metal debris into the blow molding machine. This results in the blown film having an uneven surface with spots, bulges, stretching and tearing, which in turn reduces the physical properties of the film, thereby ensuring the quality of the film formation.

[0011] Preferably, a gravity plate is rotatably connected to the side wall of the collection tank, and the gravity plate is horizontally arranged. The first magnet includes a support plate and a first magnetic block. The first magnetic block is fixedly connected to the cleaning box and is located on the upper side of the support plate. The support plate and the first magnetic block are slidably connected. The baffle is located on the lower end face of the support plate. A first cleaning gap is opened on each of the two side walls of the connecting channel. The first cleaning gap is located on the lower side of the support plate, and the gap between the top wall of the first cleaning gap and the lower end face of the support plate is... The distance is 4-6mm. A vertical through groove is opened in the cleaning box. The upper and lower ends of the through groove are connected to the first cleaning gap and the iron filings box, respectively. One end of the support plate passes through the through groove, and a push block is connected to the end of the support plate that passes through the through groove. A tension spring is provided between the push block and the outer wall of the cleaning box. A second inclined surface is provided on the push block. A push rod is provided on the cleaning box. One end of the push rod extends into the collection groove and is slidably connected to the lower end face of the gravity plate. The other end of the push rod is slidably engaged with the second inclined surface.

[0012] When the plastic raw material enters the flow chamber, due to the higher density and mass of the metal fragments, they are deflected towards the collection trough as they move forward under the influence of gravity. The deflected metal fragments fall into the collection trough and onto the upper surface of the gravity plate. As the metal fragments accumulate on the gravity plate, their weight increases, pushing the gravity plate downwards under gravity. This pushes the push rod, which is slidably connected to the lower surface of the gravity plate, causing it to slide vertically downwards. During this process, the second inclined surface converts the downward movement of the push rod into the horizontal sliding of the push block, simultaneously causing the support plate to slide horizontally within the cleaning box. During this movement, the metal fragments attached to the surface of the support plate slide along with it, passing through the first cleaning gap into the flow channel. At this point, the metal fragments detach from the first magnet. Within the magnetic field range, metal debris, under the influence of gravity, detaches from the surface of the support plate and falls into the scrap box below through the channel. As the pusher continues to slide, the metal debris adhering to the surface of the support plate comes to the side wall of the channel away from the connecting channel. Under the action of the side wall, the metal debris adhering to the surface of the support plate is scraped and cleaned. The scraped metal debris falls into the scrap box below through the channel. Through the coordinated design of the gravity plate, push rod, pusher, and support plate, the weight change of the continuously accumulating metal debris on the gravity plate drives the support plate to move in the channel, thereby collecting the accumulated metal debris on the support plate. This prevents the metal debris from accumulating too thickly on the support plate, which would weaken the magnetic field strength of the first magnetic block, reduce the adsorption efficiency, and shrink the adsorption range, thus affecting its adsorption effect on metal debris. This ensures the adsorption effect of the first magnetic block on metal debris.

[0013] Furthermore, the distance between the top wall of the first cleaning gap and the lower end face of the support plate is set at 4-6 mm. By limiting the distance between the top wall of the first cleaning gap and the lower end face of the support plate, plastic raw materials are prevented from passing through the first cleaning gap and entering the channel, thus avoiding waste of plastic raw materials. At the same time, the gap is also prevented from being too large, which would reduce the vacuum of the equipment, affect the material conveying power, and cause the material to be conveyed poorly.

[0014] Preferably, the bottom wall of the connecting channel connected to the flow cavity has rounded corners, and a second magnet is installed in the cleaning box. The second magnet is embedded in the rounded corners and is tangent to the bottom wall of the connecting channel and the inner wall of the flow cavity, respectively. The widths of the first magnet and the second magnet are equal.

[0015] Under the influence of airflow, the plastic raw material and some metal debris that were not attracted by the first magnet in the connecting channel continue to move forward. When they reach the second magnet, some of the metal debris near the second magnet is attracted to the surface of the second magnet by its magnetic field. The metal debris that is not attracted moves along the direction of airflow. At the same time, under the influence of the second magnet's magnetic field, the metal debris is deflected to one side of the second magnet as it moves forward. The deflected metal debris is shifted towards the collection tank below and falls into the collection tank. Through the design of the second magnet, the metal debris that was not attracted by the first magnet is attracted a second time, which effectively reduces the metal debris content in the plastic raw material. At the same time, the deflection of the metal debris under the influence of the second magnet's magnetic field and its falling into the collection tank prevents the metal debris from entering the blow molding machine and causing the blown film to have an uneven surface, spots, bulges, stretching and tearing, which would reduce the physical properties of the film and thus ensure the quality of the film.

[0016] Furthermore, the rounded corner design provides a smooth transition for the plastic raw material and airflow. Compared to a right-angle design, the rounded corner design can prevent metal debris from accumulating at the connection between the connecting channel and the flow cavity, keeping the flow channel unobstructed and the shape regular. This prevents turbulence caused by metal debris accumulation, thus avoiding the complex and irregular movement trajectory of metal debris in the airflow. This would prevent some metal debris from entering the blow molding machine, causing the blown film to have an uneven surface with spots, bulges, stretching, and tearing, which would reduce the physical properties of the film. This ensures the quality of the formed film.

[0017] Preferably, the second magnet includes an arc-shaped plate and a second magnetic block. The second magnetic block is fixedly connected to the cleaning box and located on the lower side of the arc-shaped plate. The second magnetic block and the arc-shaped plate are slidably connected. The two ends of the arc-shaped plate are tangent to the bottom wall of the connecting channel and the inner side wall of the flow cavity, respectively. A second cleaning gap is provided on both sides of the connecting channel. The second cleaning gap is located on the lower side of the arc-shaped plate, and the distance between the top wall of the second cleaning gap and the lower end face of the arc-shaped plate is 2-4 mm. The upper and lower ends of the through groove are connected to the second cleaning gap and the scrap box, respectively. One end of the arc-shaped plate passes through the through groove, and the end of the arc-shaped plate passing through the through groove is connected to the push block.

[0018] As the pusher slides horizontally, it causes the curved plate to slide horizontally within the cleaning box. During this movement, metal debris adhering to the surface of the curved plate slides along with it, passing through the second cleaning gap and into the through slot. At this point, the metal debris leaves the magnetic field range of the second magnetic block. Under the influence of gravity, the metal debris detaches from the surface of the curved plate and falls into the scrap box below through the through slot. As the pusher continues to slide, the metal debris adhering to the surface of the curved plate comes to the side wall of the through slot away from the connecting channel. Under the action of the side wall, the metal debris adhering to the surface of the curved plate is further removed. The metal shavings are scraped off and fall into the metal shavings box below. Through the coordinated design of the arc-shaped plate and the second cleaning gap, the weight change of the continuously accumulating metal shavings on the gravity plate drives the arc-shaped plate to move into the through groove, thereby collecting the accumulated metal shavings on the arc-shaped plate. This prevents the metal shavings from accumulating too thickly on the arc-shaped plate, which would weaken the magnetic field strength of the second magnetic block, reduce the adsorption efficiency, and shrink the adsorption range, thus affecting its adsorption effect on metal shavings. This ensures the adsorption effect of the second magnetic block on metal shavings, thereby ensuring the quality of film formation.

[0019] Furthermore, the distance between the top wall of the second cleaning gap and the lower end face of the arc plate is set to 2-4 mm. By limiting the distance between the top wall of the second cleaning gap and the lower end face of the arc plate, plastic raw materials are prevented from passing through the second cleaning gap and entering the channel, thus avoiding waste of plastic raw materials. At the same time, the gap is also prevented from being too large, which would reduce the vacuum of the equipment, affect the material conveying power, and cause the material to be conveyed poorly.

[0020] Preferably, the cleaning box is equipped with a flow stabilizer plate, the two ends of which are connected to the two side walls of the flow passage cavity. The flow stabilizer plate is arc-shaped, and the end of the flow stabilizer plate near the connecting channel is flush with the bottom wall of the connecting channel. The distance between the lower end face of the flow stabilizer plate and the bottom surface of the connecting channel is 1-3 mm. The end of the flow stabilizer plate near the collection tank is flush with the inner side wall of the flow passage cavity. The vertical projection of the end of the flow stabilizer plate near the collection tank is located inside the collection tank.

[0021] The design of the flow stabilizer plate can follow the movement trajectory of metal debris that has not been attracted by the second magnet, guiding the metal debris into the collection tank. At the same time, it avoids the airflow in the turbulent state from rolling up the metal debris, causing some metal debris to enter the blow molding machine. This would result in the blown film having an uneven surface with spots, bulges, stretching and tearing, which would reduce the physical properties of the film and thus ensure the quality of the film formation.

[0022] Preferably, the cleaning box is provided with a guide plate, and the multiple guide plates are all arc-shaped and are equidistant. The end of the multiple guide plates near the connecting channel is flush with the inner side wall of the flow cavity, and the vertical projection of the end of the multiple guide plates near the discharge port is located outside the collection tank.

[0023] The design of the guide plate guides the plastic raw material to the outlet and then into the vacuum hopper. It also prevents turbulence when the gas flows from the connecting channel through the flow chamber to the outlet, avoiding the scattering of plastic raw material into the collection tank and thus preventing waste. Furthermore, it prevents turbulent airflow from carrying up metal debris, which could then enter the blow molding machine and cause uneven surfaces, spots, bulges, stretching, and tearing in the blown film, ultimately reducing its physical properties. This design ensures the quality of the blown film.

[0024] Preferably, the feed nozzle is funnel-shaped, and the small end of the feed nozzle is connected to the connecting channel. The area of ​​the large end of the feed nozzle is S3, and the area of ​​the small end is S4, wherein 2*S4≤2.5*S3≤3*S4.

[0025] When the plastic raw material arrives at the feed nozzle, the nozzle's trumpet shape and the design of its small end connecting to the connecting channel increase the airflow velocity, thereby increasing the movement speed of the plastic raw material carried within the airflow. As the plastic raw material continues to move forward into the connecting channel, it collides perpendicularly with the first inclined surface on the baffle. The trumpet shape of the feed nozzle gives the plastic raw material a stronger impact force, which can better shake off metal debris attached to the raw material and break up clumps of raw material. This prevents metal debris from remaining on the surface of the plastic raw material and entering the blow molding machine with the plastic raw material, causing the blown film to have an uneven surface, spots, bulges, stretching and tearing, and ultimately reducing the physical properties of the film, thus ensuring the quality of the formed film.

[0026] The present invention also provides a method for using the feeding mechanism of the above-mentioned plastic blown film machine, comprising the following steps:

[0027] S1. Equipment installation and operation: Connect the vacuum hopper to the feed port of the plastic blow molding machine, connect the raw material conveying pipe to the feed nozzle, and start the vacuum generator;

[0028] S2. Cleaning and collecting metal debris in plastic raw materials: Plastic raw materials enter through the feed nozzle. Magnetic blocks No. 1 and No. 2 adsorb some of the metal debris in the plastic raw materials passing through the connecting channel. The metal debris that is not adsorbed falls into the collection tank under the guidance of magnetic block No. 2 and gravity.

[0029] S3. Clean and collect metal debris on the support plate and the arc plate: After the metal debris in the collection tank accumulates to the set weight, the gravity plate is pushed to deflect downwards under the action of gravity. The metal debris on the gravity plate falls into the iron scrap box. At the same time, the push rod is pushed downwards. The downward-moving push rod cooperates with the second inclined surface on the push block, thereby driving the arc plate and the support plate to slide horizontally. This causes the arc plate and the support plate with metal debris to break away from the magnetic field force range generated by the first and second magnetic blocks. The metal debris is unbound and falls into the iron scrap box through the through slot under the action of gravity.

[0030] S4. Remove metal debris: After completing film production, turn off the vacuum generator, remove the metal scrap box from the cleaning box, and remove the metal debris from the metal scrap box.

[0031] S4: Remove metal debris: Remove the metal scrap box from the cleaning chamber and remove the metal debris from the metal scrap box.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. This invention utilizes the design of a primary magnet and a collection tank. The primary magnet adsorbs metal fragments from the plastic raw material, while the collection tank takes advantage of the high density and mass of the metal fragments. Under the influence of gravity, the metal fragments that are not adsorbed deflect downwards into the collection tank and fall into it. This prevents metal fragments from being carried into the blow molding machine from entering the plastic raw material, which would cause the blown film to have an uneven surface, spots, bulges, stretching and tearing, and thus reduce the physical properties of the film, thereby ensuring the quality of the film formation.

[0034] 2. This invention utilizes the combination of a gravity plate, push rod, push block, support plate, and arc plate. By leveraging the weight change of metal debris on the gravity plate, the support plate and arc plate are driven to move within the through groove, thereby collecting the metal debris accumulated on the support plate and arc plate. This prevents the metal debris from accumulating too thickly on the surface of the support plate and arc plate, which would weaken the magnetic field strength of the first and second magnetic blocks, reduce their adsorption efficiency, and shrink their adsorption range, thus affecting their adsorption effect on metal debris. This ensures the adsorption effect of the first and second magnetic blocks on metal debris, thereby guaranteeing the film formation quality.

[0035] 3. The present invention, through the design of the feed nozzle and the baffle, enables the plastic raw material passing through the feed nozzle to have a faster speed and stronger impact force. When it impacts the first inclined surface on the baffle perpendicularly, it disperses the agglomerated plastic raw material and shakes off the metal debris on the surface of the plastic raw material through the impact, thus preventing the plastic raw material from agglomerating and thus preventing the metal debris inside the agglomerated plastic raw material from being cleaned. This prevents the metal debris from entering the blow molding machine, thereby ensuring the quality of film formation. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of the feeding mechanism of a plastic blown film machine;

[0037] Figure 2 for Figure 1 Sectional view at CC;

[0038] Figure 3 for Figure 2 Sectional view at point AA;

[0039] Figure 4 for Figure 2 A magnified view of a section at point B in the middle;

[0040] Figure 5 This is an axial sectional view of the front of the cleaning box in this invention;

[0041] Figure 6 This is a rear axial sectional view of the cleaning box in this invention;

[0042] Figure 7 for Figure 6 A schematic diagram showing the cleaning status of the central support plate and the curved plate;

[0043] Figure 8 Instructions for using the feeding mechanism of a plastic blown film machine.

[0044] In the diagram: 1. Vacuum hopper; 12. Vacuum generator; 2. Cleaning box; 21. Flow passage; 211. Flow stabilizer; 212. Flow guide plate; 22. Feed nozzle; 23. Discharge port; 24. Collection trough; 25. Through trough; 26. Cleaning gap 1; 27. Cleaning gap 2; 28. Connecting channel; 3. Magnet 1; 31. Support plate; 32. Magnetic block 1; 33. Baffle; 34. Inclined surface 1; 4. Magnet 2; 41. Arc plate; 42. Magnetic block 2; 5. Gravity plate; 51. Push rod; 52. Push block; 521. Inclined surface 2; 53. Tension spring; 6. Scrap box. Detailed Implementation

[0045] Please see Figures 1 to 8 This invention provides a feeding mechanism for a plastic blown film machine and its usage method. The technical solution is as follows:

[0046] A feeding mechanism for a plastic blown film machine and its usage method include a vacuum hopper 1, a vacuum generator 12, a first magnet 3, and a cleaning box 2. The cleaning box 2 has a flow passage 21, a feed nozzle 22, and a discharge port 23. The feed nozzle 22 and the discharge port 23 are respectively connected to the side walls on both sides of the flow passage 21, and the feed nozzle 22 is located above the discharge port 23. The discharge port 23 is connected to the inner side of the vacuum hopper 1. The vacuum hopper 1 is connected to the vacuum generator 12. A collection groove 24 is provided on the bottom of the flow passage 21, and the collection groove 24 is located on the side away from the discharge port 23. A scrap box 6 is provided at the bottom of the collection groove 24. A connecting channel 28 is provided between the feed nozzle 22 and the flow passage 21. The connecting channel 28 is horizontally arranged. The first magnet 3 is located on the side wall of the connecting channel 28, and the width of the first magnet 3 is equal to the width of the top wall of the connecting channel 28.

[0047] Please see Figure 2 , Figure 4 , Figure 5 Magnet 3 is located on the top wall of connecting channel 28, and the lower end face of magnet 3 is flush with the top wall of connecting channel 28. Multiple baffles 33 are evenly distributed on the lower end face of magnet 3. An inclined surface 34 is provided on the side wall of the baffle 33 away from the flow cavity 21. The feed nozzle 22 is set at an angle to the connecting channel 28, and the axial direction of the feed nozzle 22 is perpendicular to the inclined surface 34. The projected area of ​​the feed nozzle 22 along the axial direction is S1. The projection of the multiple inclined surfaces 34 in the axial direction of the feed nozzle 22 is a complete projection surface, and the projected area is S2, S1≤S2. The feed nozzle 22 is trumpet-shaped, and the small end of the feed nozzle 22 is connected to the connecting channel 28. The area of ​​the large end of the feed nozzle 22 is S3, and the area of ​​the small end is S4, 2*S4≤2.5*S3≤3*S4.

[0048] Please see Figure 1 , Figure 3 , Figure 5 , Figure 6 , Figure 7A gravity plate 5 is rotatably connected to the side wall of the collection tank 24. The gravity plate 5 is horizontally positioned. The first magnet 3 includes a support plate 31 and a first magnetic block 32. The first magnetic block 32 is fixedly connected to the cleaning box 2 and is located on the upper side of the support plate 31. The support plate 31 and the first magnetic block 32 are slidably connected. A baffle 33 is provided on the lower end face of the support plate 31. A first cleaning gap 26 is opened on both side walls of the connecting channel 28. The first cleaning gap 26 is located on the lower side of the support plate 31, and the distance between the top wall of the first cleaning gap 26 and the lower end face of the support plate 31 is 5m. The cleaning box 2 has a vertical through groove 25. The upper and lower ends of the through groove 25 are connected to the first cleaning gap 26 and the iron filings box 6, respectively. One end of the support plate 31 passes through the through groove 25, and a push block 52 is connected to the end of the support plate 31 that passes through the through groove 25. A tension spring 53 is provided between the push block 52 and the outer wall of the cleaning box 2. A second inclined surface 521 is provided on the push block 52. A push rod 51 is provided on the cleaning box 2. One end of the push rod 51 extends into the collection groove 24 and is slidably connected to the lower end face of the gravity plate 5. The other end of the push rod 51 is slidably engaged with the second inclined surface 521.

[0049] Please see Figure 2 , Figure 4 The bottom wall of the connecting channel 28, which connects to the flow cavity 21, has rounded corners. A second magnet 4 is installed inside the cleaning box 2, embedded within the rounded corners. The second magnet 4 is tangent to both the bottom wall of the connecting channel 28 and the inner wall of the flow cavity 21. The widths of the first magnet 3 and the second magnet 4 are equal. The second magnet 4 includes an arc-shaped plate 41 and a second magnetic block 42. The second magnetic block 42 is fixedly connected to the cleaning box 2, located below the arc-shaped plate 41, and slidably connected to the arc-shaped plate 41. The two ends of the plate 41 are tangent to the bottom wall of the connecting channel 28 and the inner side wall of the flow cavity 21, respectively. The two side walls of the connecting channel 28 are provided with a second cleaning gap 27. The second cleaning gap 27 is located on the lower side of the arc plate 41, and the distance between the top wall of the second cleaning gap 27 and the lower end face of the arc plate 41 is 3mm. The upper and lower ends of the through groove 25 are connected to the second cleaning gap 27 and the iron chip box 6, respectively. One end of the arc plate 41 passes through the through groove 25, and the end of the arc plate 41 that passes through the through groove 25 is connected to the push block 52.

[0050] Please see Figure 2The cleaning box 2 is equipped with a flow stabilizer plate 211. Both ends of the flow stabilizer plate 211 are connected to the two side walls of the flow passage 21. The flow stabilizer plate 211 is arc-shaped. The end of the flow stabilizer plate 211 near the connecting channel 28 is flush with the bottom wall of the connecting channel 28. The distance between the lower end surface of the flow stabilizer plate 211 and the bottom surface of the connecting channel 28 is 2mm. The end of the flow stabilizer plate 211 near the collection tank 24 is flush with the inner side wall of the flow passage 21. The vertical projection of the end of the flow stabilizer plate 211 near the collection tank 24 is located inside the collection tank 24. The cleaning box 2 is equipped with multiple flow guide plates 212. Multiple flow guide plates 212 are arc-shaped and are equidistant. The ends of multiple flow guide plates 212 near the connecting channel 28 are flush with the inner side wall of the flow passage 21. The vertical projection of the ends of multiple flow guide plates 212 near the discharge port 23 is located outside the collection tank 24.

[0051] Please see Figures 1 to 8 The following is a method for using the feeding mechanism of a plastic blown film machine:

[0052] S1. Equipment installation and operation: When feeding the blow molding machine, connect the vacuum hopper 1 to the feed port of the blow molding machine and connect the feed nozzle 22 to the conveying pipe for conveying raw materials. At this time, start the vacuum generator 12 to remove the air from the vacuum hopper 1, and the vacuum hopper 1 is in a negative pressure state.

[0053] S2. Cleaning and collecting metal debris from plastic raw materials: When the vacuum hopper 1 is under negative pressure, external gas enters the vacuum hopper 1 through the conveying pipe, inlet 22, connecting channel 28, flow chamber 21, and outlet 23. During this process, the airflow carries the plastic raw material forward. When the plastic raw material reaches the inlet 22, the inlet 22 is funnel-shaped, and its small end is connected to the connecting channel 28, which increases the airflow velocity and thus increases the movement speed of the plastic raw material carried in the airflow. As the plastic raw material continues to move forward into the connecting channel 28, the rapidly moving plastic raw material collides perpendicularly with the first inclined surface 34 on the baffle 33. The impact and reaction forces generated by the perpendicular collision with the first inclined surface 34 disperse the agglomerated plastic raw material. At the same time, the impact and vibration generated can break the adhesion between the metal debris particles and the surface of the plastic raw material, thus removing the metal debris that was originally attached to the surface of the plastic raw material. Fine metal fragments are shaken off. At this time, some of the metal fragments are attracted to the surface of the support plate 31 under the magnetic force of the first magnetic block 32. Under the action of airflow, the plastic raw material and some metal fragments in the connecting channel 28 continue to move forward. When they reach the top of the second magnet 4, some of the metal fragments near the second magnet 4 are attracted to the surface of the arc plate 41 under the magnetic force of the second magnetic block 42. The metal fragments that are not attracted move along the airflow direction. At the same time, under the action of the magnetic force of the second magnetic block 42, the metal fragments deflect to one side of the second magnetic block 42 during their forward movement. The deflected metal fragments move towards the inner wall of the flow stabilizer 211 and fall into the collection tank 24 under the action of the flow stabilizer 211, and come to the upper surface of the gravity plate 5. Meanwhile, since the plastic raw material is not affected by the magnetic force of the second magnetic block 42, it moves along the airflow direction and is guided by the guide plate 212 to the discharge port 23, and then enters the vacuum hopper 1.

[0054] S3. Cleaning and collecting metal debris on the support plate and the curved plate: As metal debris accumulates on the gravity plate 5, its weight increases, pushing the gravity plate 5 downwards under gravity. This pushes the push rod 51, which is slidably connected to the lower end of the gravity plate 5, causing it to slide downwards vertically. During this process, the downward movement of the push rod 51 is converted into the horizontal sliding of the push block 52 by the setting of the second inclined surface 521. During the sliding of the push block 52, the tension spring 53 is pulled, which simultaneously drives the support plate 31 and the curved plate 41 to slide horizontally within the cleaning box 2. During the movement, the surfaces of the support plate 31 and the curved plate 41... The attached metal debris slides along and passes through the first cleaning gap 26 and the second cleaning gap 27 to enter the through groove 25. At this time, the metal debris leaves the magnetic field range of the first magnet 3 and the second magnet 4. Under the action of gravity, the metal debris leaves the surface of the support plate 31 and the arc plate 41 and falls into the iron scrap box 6 below through the through groove 25. As the push block 52 continues to slide, the metal debris adhering to the surface of the support plate 31 and the arc plate 41 comes to the side wall of the through groove 25 away from the connecting channel 28. Under the action of the side wall, the metal debris adhering to the surface of the support plate 31 and the arc plate 41 is scraped and cleaned. The scraped metal debris falls into the iron scrap box 6 below.

[0055] When the gravity plate 5 is twisted to a certain tilt angle, the metal debris on the gravity plate 5 slides off and falls into the scrap box 6 below through the collection groove 24. At this time, the elastic potential energy of the tension spring 53 is released, pulling the push block 52 to slide in the opposite direction in the horizontal direction. During this process, under the action of the second inclined surface 521, the push rod 51 moves upward in the vertical direction, thereby pushing the gravity plate 5 to reset and return to the horizontal position. At the same time, the push block 52 pushes the support plate and the arc plate 41 to move in the opposite direction. During the movement, the metal debris attached to the surfaces of the support plate 31 and the arc plate 41 slides along with them and passes through the first cleaning gap 2 respectively. 6 and the second cleaning gap 27 enter the through groove 25. At this time, the metal debris leaves the magnetic field range of the first magnet 3 and the second magnet 4. Under the action of gravity, the metal debris leaves the surface of the support plate 31 and the arc plate 41 and falls into the iron scrap box 6 below through the through groove 25. As the push block 52 continues to slide, the metal debris adhering to the surface of the support plate 31 and the arc plate 41 comes to the side wall of the through groove 25 away from the connecting channel 28. Under the action of the side wall, the metal debris adhering to the surface of the support plate 31 and the arc plate 41 is scraped and cleaned. The scraped metal debris falls into the iron scrap box 6 below.

[0056] S4. Remove metal debris: After the film production is completed, turn off the vacuum generator 12, remove the scrap box 6 from the cleaning box 2, and remove the metal debris from the scrap box 6.

[0057] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. A feeding mechanism for a plastic blown film machine, characterized in that, The system includes a vacuum hopper (1), a vacuum generator (12), a first magnet (3), and a cleaning box (2). The cleaning box (2) has a flow passage (21), an inlet (22), and an outlet (23). The inlet (22) and outlet (23) are respectively connected to the side walls on both sides of the flow passage (21), with the inlet (22) located above the outlet (23). The outlet (23) is connected to the inner side of the vacuum hopper (1). The vacuum hopper (1) is connected to the vacuum generator (12). The flow passage (21) is connected, and a collection groove (24) is provided on the bottom of the flow passage (21). The collection groove (24) is located on the side away from the discharge port (23). A scrap box (6) is provided at the bottom of the collection groove (24). A connecting channel (28) is provided between the feed nozzle (22) and the flow passage (21). The connecting channel (28) is horizontally arranged. The first magnet (3) is located on the side wall of the connecting channel (28), and the width of the first magnet (3) is equal to the width of the top wall of the connecting channel (28).

2. The feeding mechanism of a plastic blown film machine according to claim 1 and its method of use, characterized in that, The first magnet (3) is located on the top wall of the connecting channel (28), and the lower end face of the first magnet (3) is flush with the top wall of the connecting channel (28). Multiple baffles (33) are evenly distributed on the lower end face of the first magnet (3). A first inclined surface (34) is provided on the side wall of the baffle (33) away from the flow cavity (21). The feed nozzle (22) is set at an angle to the connecting channel (28), and the axial direction of the feed nozzle (22) is perpendicular to the first inclined surface (34). The projected area of ​​the feed nozzle (22) along the axial direction is S1. The projection of the multiple first inclined surfaces (34) in the axial direction of the feed nozzle (22) is a complete projection surface, and the projected area is S2. S1≤S2.

3. The feeding mechanism of a plastic blown film machine according to claim 2, characterized in that, The sidewall of the collection trough (24) is rotatably connected to a gravity plate (5), which is horizontally arranged. The first magnet (3) includes a support plate (31) and a first magnetic block (32). The first magnetic block (32) is fixedly connected to the cleaning box (2). The first magnetic block (32) is located on the upper side of the support plate (31), and the support plate (31) and the first magnetic block (32) are slidably connected. The baffle (33) is located on the lower end face of the support plate (31). A first cleaning gap (26) is opened on both sides of the connecting channel (28). The first cleaning gap (26) is located on the lower side of the support plate (31), and the distance between the top wall of the first cleaning gap (26) and the lower end face of the support plate (31) is 4-6 mm. The cleaning box (2) has a vertical through groove (25) inside. The upper and lower ends of the through groove (25) are connected to the first cleaning gap (26) and the scrap box (6) respectively. One end of the support plate (31) passes through the through groove (25), and a push block (52) is connected to the end of the support plate (31) that passes through the through groove (25). A tension spring (53) is provided between the push block (52) and the outer wall of the cleaning box (2). A second inclined surface (521) is provided on the push block (52). A push rod (51) is provided on the cleaning box (2). One end of the push rod (51) extends into the collection groove (24) and is slidably connected to the lower end face of the gravity plate (5). The other end of the push rod (51) is slidably engaged with the second inclined surface (521).

4. The feeding mechanism of a plastic blown film machine according to claim 3, characterized in that, The bottom wall of the connecting channel (28) connected to the flow cavity (21) is provided with rounded corners. A second magnet (4) is installed in the cleaning box (2). The second magnet (4) is embedded in the rounded corners, and the second magnet (4) is tangent to the bottom wall of the connecting channel (28) and the inner wall of the flow cavity (21) respectively. The width of the first magnet (3) and the second magnet (4) are equal.

5. The feeding mechanism of a plastic blown film machine according to claim 4, characterized in that, The second magnet (4) includes an arc-shaped plate (41) and a second magnetic block (42). The second magnetic block (42) is fixedly connected to the cleaning box (2). The second magnetic block (42) is located on the lower side of the arc-shaped plate (41), and the second magnetic block (42) and the arc-shaped plate (41) are slidably connected. The two ends of the arc-shaped plate (41) are tangent to the bottom wall of the connecting channel (28) and the inner wall of the flow cavity (21), respectively. The second magnetic block (42) is provided on both sides of the connecting channel (28). The second cleaning gap (27) is located on the lower side of the arc plate (41), and the distance between the top wall of the second cleaning gap (27) and the lower end face of the arc plate (41) is 2-4 mm. The upper and lower ends of the through groove (25) are connected to the second cleaning gap (27) and the scrap box (6) respectively. One end of the arc plate (41) passes through the through groove (25), and the end of the arc plate (41) passing through the through groove (25) is connected to the push block (52).

6. The feeding mechanism of a plastic blown film machine according to claim 4, characterized in that, The cleaning box (2) is equipped with a flow stabilizer plate (211). The two ends of the flow stabilizer plate (211) are connected to the two side walls of the flow passage cavity (21). The flow stabilizer plate (211) is arc-shaped. The end of the flow stabilizer plate (211) near the connecting channel (28) is flush with the bottom wall of the connecting channel (28). The distance between the lower end face of the flow stabilizer plate (211) and the bottom face of the connecting channel (28) is 1-3mm. The end of the flow stabilizer plate (211) near the collection tank (24) is flush with the inner side wall of the flow passage cavity (21). The vertical projection of the end of the flow stabilizer plate (211) near the collection tank (24) is located in the collection tank (24).

7. The feeding mechanism of a plastic blown film machine according to claim 6, characterized in that, The cleaning box (2) is provided with a guide plate (212). The multiple guide plates (212) are all arc-shaped and are equidistant. The end of the multiple guide plates (212) near the connecting channel (28) is flush with the inner wall of the flow cavity (21). The vertical projection of the end of the multiple guide plates (212) near the discharge port (23) is located outside the collection tank (24).

8. The feeding mechanism of a plastic blown film machine according to claim 2, characterized in that, The feed nozzle (22) is trumpet-shaped, and the small end of the feed nozzle (22) is connected to the connecting channel (28). The area of ​​the large end of the feed nozzle (22) is S3, and the area of ​​the small end is S4, wherein 2*S4≤S3≤3*S4.

9. A method of using a feeding mechanism for a plastic blown film machine, characterized in that, The method of using the plastic blown film machine shall at least use the feeding mechanism of the plastic blown film machine as described in any one of claims 1 to 8, as follows: S1. Equipment installation and operation: Connect the vacuum hopper (1) to the feed port of the plastic blow molding machine, connect the raw material conveying pipe to the feed nozzle (22), and start the vacuum generator (12); S2. Cleaning and collecting metal debris in plastic raw materials: Plastic raw materials enter from the feed nozzle (22). Magnetic block No. 1 (32) and magnetic block No. 2 (42) adsorb some of the metal debris in the plastic raw materials passing through the connecting channel (28). The metal debris that is not adsorbed falls into the collection tank (24) under the guidance of magnetic block No. 2 (42) and gravity. S3. Clean and collect the metal debris on the support plate (31) and the arc plate (41): After the metal debris in the collection trough (24) accumulates to the set weight, the gravity plate (5) is pushed to deflect downward under the action of gravity. The metal debris on the gravity plate (5) falls into the iron scrap box (6). At the same time, the push rod (51) is pushed to move downward. The downward-moving push rod (51) cooperates with the second inclined surface (521) on the push block (52), thereby driving the arc plate (41) and the support plate (31) to slide horizontally. This causes the arc plate (41) and the support plate (31) with metal debris to be removed from the magnetic field force range generated by the first magnetic block (32) and the second magnetic block (42). The metal debris is unbound and falls into the iron scrap box (6) through the through groove (25) under the action of gravity. S4. Remove metal debris: After the film production is completed, turn off the vacuum generator (12), take the scrap box (6) out of the cleaning box (2), and remove the metal debris from the scrap box (6).

Images