Extrusion molding process

Abstract

The invention relates to the field of plastic extruding machines, in particular to a plastic extruding process which comprises a material barrel, a material conveying screw is rotatably connected in the material barrel, a sliding box is fixedly connected to the end of the material barrel, a filter plate is slidably connected in the sliding box, an air cylinder is fixedly connected to the upper end of the material barrel, the moving end of the air cylinder is fixedly connected to the upper end of the filter plate, and a discharging pipe is fixedly connected to the front end of the sliding box. A water tank is fixedly connected to the lower end of the charging barrel, two net plates are fixedly connected into the water tank, multiple sets of steel wire brushes are installed on the inner sides of the two net plates, a drainage hole is formed in the water tank, a die head is fixedly connected to the discharging pipe, the die head is annular, a through hole is formed in the middle of the die head, a cavity is formed in the die head, and an annular opening is formed in the middle of the die head. The annular opening is communicated with the cavity, and the annular opening is downwards formed towards the middle part, so that the filter plate can be automatically cleaned under the condition that the machine head is not disassembled.

Description

Technical Field

[0001] This invention relates to the field of extruders, and more particularly to an extrusion process. Background Technology

[0002] In the plastics processing industry, extruders are core equipment, and their filter plate structure has a decisive impact on product quality and production efficiency. Traditional extruder filter plate systems generally suffer from the following technical bottlenecks: Existing technology (CN218876216U) uses a fixed filter plate structure. When impurities accumulate on the filter plate surface, causing a decrease in filtration efficiency, the machine must be stopped to disassemble the extruder head for manual cleaning or filter replacement. This process takes 30-60 minutes, and frequent disassembly and assembly can easily lead to a decrease in equipment precision, directly affecting production continuity. Simple mechanical rinsing is insufficient to thoroughly remove solidified plastic residue, increasing maintenance costs. Summary of the Invention

[0003] In view of this, the technical problem to be solved by the present invention is to provide an extrusion process that can automatically clean the filter plate without disassembling the die head.

[0004] An extrusion device includes a barrel, a feed screw rotatably connected inside the barrel, a slide box fixedly connected to the end of the barrel, a filter plate slidably connected inside the slide box, a cylinder fixedly connected to the upper end of the barrel, the moving end of the cylinder fixedly connected to the upper end of the filter plate, a discharge pipe fixedly connected to the front end of the slide box, and a water tank fixedly connected to the lower end of the barrel. Two screens are fixedly connected inside the water tank, and multiple sets of wire brushes are installed on the inner side of each of the two screens. A drain hole is provided on the water tank.

[0005] A die head is fixedly connected to the discharge pipe. The die head is annular with a through hole in the middle and a cavity inside. An annular opening is provided in the middle of the die head, which communicates with the cavity. The annular opening is downward and faces the center.

[0006] A housing is fixedly connected inside the slide box, an impeller is rotatably connected inside the housing, a drain pipe is fixedly connected to the housing, a water inlet pipe is fixedly connected to the lower end of the housing, and the drain pipe extends to the outside of the water tank.

[0007] A drive motor is fixedly connected to the barrel, a feed screw is fixedly connected to the output shaft of the drive motor, a first pulley is fixedly connected to the feed screw, and a second pulley is fixedly connected to the impeller. The first pulley and the second pulley are connected by a synchronous belt, and the diameter of the first pulley is three times that of the second pulley.

[0008] A feed hopper is fixedly connected to the upper end of the material cylinder, and the feed hopper is connected to the inside of the material cylinder.

[0009] An auxiliary roller is rotatably connected to the water tank, with the center of the auxiliary roller recessed inward.

[0010] A return box is fixedly connected to the lower end of the water tank, and the water inlet pipe extends into the return box. The opening of the water tank is located below the auxiliary roller.

[0011] The reflux chamber gradually becomes deeper from front to back.

[0012] Both mesh panels are flexible mesh panels. Attached Figure Description

[0013] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0014] Figure 1 and Figure 2 This is a schematic diagram of an extrusion equipment structure;

[0015] Figure 3 This is a schematic diagram of the filter plate structure;

[0016] Figure 4 This is a schematic diagram of the impeller structure;

[0017] Figure 5 This is a schematic diagram of the material cylinder structure;

[0018] Figure 6 This is a schematic diagram of the die head structure;

[0019] Figure 7 This is a schematic diagram of the feed hopper structure;

[0020] Figure 8 This is a schematic diagram of the material transfer screw. Detailed Implementation

[0021] The present invention will be described in detail with reference to the accompanying drawings in the embodiments of the present invention.

[0022] An extrusion device includes a barrel 101, a feed screw 102 rotatably connected inside the barrel 101, a slide box 201 fixedly connected to the end of the barrel 101, a filter plate 202 slidably connected inside the slide box 201, a cylinder 204 fixedly connected to the upper end of the barrel 101, the moving end of the cylinder 204 fixedly connected to the upper end of the filter plate 202, a discharge pipe 203 fixedly connected to the front end of the slide box 201, a water tank 501 fixedly connected to the lower end of the barrel 101, two screen plates 502 fixedly connected inside the water tank 501, multiple sets of wire brushes 503 installed on the inner side of each of the two screen plates 502, and a drain hole 506 opened on the water tank 501.

[0023] See Figure 3 and 7 -8,

[0024] When using extrusion equipment, the operator first adds plastic granules into the barrel 101, and then starts the feed screw 102 to rotate and convey the plastic granules from the rear end to the front end. During the process of conveying the plastic granules by the feed screw 102, the feed equipment heats and melts the plastic granules in the barrel 101. When the plastic granules are conveyed to the front end of the barrel 101, the plastic becomes molten.

[0025] Molten plastic enters the discharge pipe 203 through the filter plate 202 and is finally extruded through the discharge pipe 203. The filter plate 202 plays a role in filtering the molten plastic, which can filter out impurities in the molten plastic, thereby ensuring the overall quality of the extruded plastic.

[0026] Water tank 501 is used to store cold water. After the filter plate 202 has been used for a period of time, the impurities accumulated on the filter plate 202 will affect the filtration effect of the filter plate 202 itself. Conventional extruders require the operator to manually disassemble the machine head and then clean and replace the filter screen, which is a waste of time and manpower. When this equipment needs to clean the filter plate 202, the moving end of the control cylinder 204 is contracted to drive the filter plate 202 to slide downward, so that the filter plate 202 is separated from the slide box 201. This allows the filter plate 202 to extend from the lower end of the slide box 201 and directly insert into the water tank 501. At this time, the upper part of the filter plate 202 enters the slide box 201, which can block the slide box 201. At this time, the plastic cannot be extruded through the discharge pipe 203.

[0027] The filter plate 202 is immersed in the cold water in the water tank 501, which cools the filter plate and causes the impurities and plastic on the filter plate to change from a molten state to a solid state. At the same time, as the filter plate 202 descends, it inserts between the two mesh plates 502, and then the two sides of the filter plate 202 come into contact with the multiple sets of steel wire brushes 503 on the two mesh plates 502. The force of the filter plate 202 descending causes the multiple sets of steel wire brushes 503 to scrape off the solidified plastic, thereby realizing the automatic cleaning function of the filter plate 202. There is no need for the staff to disassemble the machine head or to clean and replace it manually.

[0028] The two mesh panels 502 have the functions of water permeability and impurity isolation. Cold water is discharged through the drain hole 506, while impurities are isolated in the water tank 501 to prevent blockage of the drain hole 506, and at the same time, it is convenient for staff to collect and process the impurities.

[0029] A cylinder drives the filter plate to rise and fall. Through the extension and retraction of cylinder 204, the filter plate 202 can slide vertically along the slide box 201. When the filtration efficiency of the filter plate 202 decreases due to impurity accumulation, the cylinder retracts, causing the filter plate 202 to detach from the slide box 201 and move down into the water tank 501. This design avoids the cumbersome operation of manually disassembling the machine head required by traditional equipment, significantly reducing downtime. The cold water stored in the water tank 501 rapidly cools the filter plate 202, causing the molten plastic impurities to solidify. Solid impurities are easier to peel off, reducing the energy consumption of secondary melting during manual cleaning, and also reducing the safety risks of high-temperature operation.

[0030] When the filter plate 202 descends, it is embedded between two mesh plates 502 inside the water tank 501. The wire brushes 503 on both sides scrape away solidified impurities from the surface of the filter plate through mechanical friction. The permeable structure of the mesh plate 502 allows cold water to circulate, while isolating impurities to prevent clogging of the drain hole 506, thus achieving integrated cleaning and drainage.

[0031] The downward motion of the filter plate 202 is converted into scraping power, eliminating the need for an additional drive device. The multiple sets of wire brushes 503 cover the entire surface of the filter plate, improving the scraping rate and avoiding the filter plate deformation problems caused by traditional incineration cleaning. The equipment achieves non-stop cleaning through the rapid switching of the filter plate 202, avoiding melt pressure fluctuations caused by traditional screen changing and ensuring the stability of extrusion quality.

[0032] A die head 301 is fixedly connected to the discharge pipe 203. The die head 301 is annular, with a through hole 303 in the middle. A cavity is provided inside the die head 301. An annular opening 302 is provided in the middle of the die head 301. The annular opening 302 communicates with the cavity and is opened downward towards the center.

[0033] See Figure 6 ,

[0034] The plastic discharged through the discharge pipe 203 enters the cavity of the die head 301 and then exits through the annular opening 302. The operator passes the cable through the through hole 303. When the cable passes through the through hole 303, the plastic in contact with the annular opening 302 can automatically wrap around the cable. Since the annular opening 302 is opened downwards towards the center, when the plastic is extruded, the plastic can move downwards automatically with the cable, thus perfectly adhering to the surface of the cable and preventing the plastic sheath from breaking.

[0035] A housing 601 is fixedly connected inside the slide box 201. An impeller 602 is rotatably connected inside the housing 601. A drain pipe 604 is fixedly connected to the housing 601. A water inlet pipe 603 is fixedly connected to the lower end of the housing 601. The drain pipe 604 extends to the outside of the water tank 501.

[0036] See Figure 4 ,

[0037] During the automatic cleaning of filter plate 202, the impeller 602 is controlled to rotate, and under centrifugal force, the water in the housing 601 is discharged into the water tank 501 through the drain pipe 604. At the same time, under negative pressure, external water is drawn into the housing 601 through the water inlet pipe 603 to achieve the function of cold water flow. This structure enables the cold water inside the water tank 501 to flow, thereby promoting the cooling and solidification of impurities on the surface of filter plate 202, and at the same time promoting the removal of impurities from filter plate 202, preventing impurities from re-adhering to filter plate 202.

[0038] The annular opening 302 faces downwards towards the center, utilizing the weight of the molten plastic to create a downward traction force. When the plastic is extruded from the cavity through the annular opening 302, it forms a continuous downward flow trend under the action of gravity, dynamically matching the downward movement speed of the cable, effectively eliminating the skin accumulation problem caused by the inertia of the melt in traditional right-angle dies.

[0039] When the cable passes through the through hole 303, its outer surface maintains a dynamic gap with the discharge edge of the annular opening 302. As the cable moves, the melt forms a continuous U-shaped coating layer under the guiding effect of the annular opening 302, achieving molecular-level adhesion to the cable surface through adhesive force, thus improving peel strength.

[0040] The turbulent pulsation formed by the water circulation keeps impurities in the water tank 501 in a suspended state, preventing impurities from redepositing on the surface of the filter plate 202.

[0041] A drive motor 401 is fixedly connected to the material cylinder 101. The material conveying screw 102 is fixedly connected to the output shaft of the drive motor 401. A first pulley 402 is fixedly connected to the material conveying screw 102. A second pulley 403 is fixedly connected to the impeller 602. The first pulley 402 and the second pulley 403 are connected by a synchronous belt. The diameter of the first pulley 402 is three times that of the second pulley 403.

[0042] See Figure 5 ,

[0043] The drive motor 401 drives the feed screw 102 to rotate, realizing the function of conveying and extruding plastic. At the same time, the first pulley 402 and the second pulley 403 work together to drive the impeller 602 to rotate, thereby realizing the function of cold water flowing in the water tank 501, which facilitates the dissipation of heat in the cold water and realizes the function of accelerating cooling.

[0044] Since the diameter of the first pulley 402 is three times that of the second pulley 403, it can accelerate the impeller 602, thereby increasing the water flow speed.

[0045] A feed hopper 103 is fixedly connected to the upper end of the material cylinder 101, and the feed hopper 103 is connected to the inside of the material cylinder 101.

[0046] See Figure 1 ,

[0047] The feed hopper 103 is used to store plastic granules. When the feed screw 102 conveys the plastic granules forward, the plastic granules in the feed hopper 103 can automatically descend and enter the material cylinder 101, realizing the function of automatically replenishing the material cylinder 101 with raw materials without the need for continuous manual addition by the staff.

[0048] An auxiliary roller 504 is rotatably connected to the water tank 501, and the middle of the auxiliary roller 504 is recessed inward.

[0049] See Figure 3 ,

[0050] After the cable is covered with plastic, the staff places the cable on the lower end of the auxiliary roller 504 at a 90° angle and then discharges it. At this time, the cold water discharged from the drain hole 506 can be poured on the corner of the cable, thereby achieving the function of cooling and shaping the cable. After the cable is shaped at the corner, it is easy for the collection roller to wind and collect the cable.

[0051] Because the auxiliary roller 504 is recessed in the middle, it serves to limit the cable and prevent the cable from shifting during transmission.

[0052] When the auxiliary roller 504 guides the cable to a 90° turn, the cold water discharged from the drain hole 506 precisely impacts the bent part of the cable. This area is a stress concentration point of the plastic coating layer. The cold water causes the local temperature to drop rapidly through forced convection, effectively inhibiting the skin cracking caused by thermal stress.

[0053] The impact of cold water triggers a rapid phase change in the molten plastic, forming a dense crystalline layer. The crystallinity of this region is higher than that of traditional straight pipe cooling, which increases the tensile strength of the coating layer.

[0054] A return box 505 is fixedly connected to the lower end of the water tank 501, and the water inlet pipe 603 extends into the return box 505. The opening of the water tank 501 is located below the auxiliary roller 504.

[0055] See Figure 3 ,

[0056] The cold water discharged from the drain hole 506 directly enters the return box 505. Since the water inlet pipe 603 extends into the return box 505, the water inlet pipe 603 can pump the cold water back into the water tank 501 under negative pressure, realizing the function of cold water circulation. Furthermore, under the action of the screen plate 502, impurities will not enter the return box 505, thus saving water and filtering water. The water tank 501 simultaneously cools the filter plate 202 and the cables.

[0057] The reflux box 505 gradually becomes darker from front to back.

[0058] See Figure 3 ,

[0059] After being discharged through the drain hole 506, the cold water can automatically flow into the deepest part of the return box 505, which makes it easy to pump the cold water back into the water tank 501 through the water inlet pipe 603, so as to realize the cold water circulation and heat dissipation function.

[0060] Both 502 mesh panels are flexible mesh panels.

[0061] See Figure 3 ,

[0062] When the filter plate 202 descends and comes into contact with the two mesh plates 502, the two mesh plates 502 can undergo adaptive elastic deformation, thereby preventing the mesh plates 502 from deforming after prolonged contact, thus avoiding affecting the cleaning ability of the multiple sets of wire brushes 503 on the filter plate 202.

[0063] The process of processing cables using the extrusion equipment of claim 8 includes the following steps:

[0064] Step 1: Plastic granules enter the screw extruder through the hopper and are heated and plasticized. They are evenly distributed through the cavity of the die 301, and the molten plastic is extruded downward from the annular opening 302 of the die 301 to coat the surface of the cable.

[0065] Step 2: During the coating process, cylinder 204 drives filter plate 202 to descend into water tank 501. Impeller 602 discharges cold water in water tank 501 through drain pipe 604, while simultaneously drawing in fresh water through inlet pipe 603, forming a circulating water flow that impacts the surface of filter plate 202.

[0066] Step 3: After the coated cable enters the water tank 501, the cable is guided to form a 90° turn by the concave structure of the auxiliary roller 504. The cold water discharged from the drain hole 506 precisely impacts the corner of the cable, and the low temperature water flow quickly cools the coating layer, eliminating the surface cracking caused by thermal stress.

[0067] Step 4: The grooved sidewall of the auxiliary roller 504 contacts the cable surface, reducing friction through hydrodynamic pressure effect and preventing cable deviation;

[0068] Step 5: After shaping, the cable is wound up at a uniform speed by a traction device, and the cable laying mechanism ensures that the cable layers are neatly stacked.

Claims

1. An extrusion apparatus characterized by: The utility model relates to a plastic cable coating device, including the cylinder, rotate and connect with the cylinder inside transmission screw rod, the cylinder end fixedly connected with the slide box, the slide box inside slide connection has the filter plate, the cylinder upper end fixedly connected with the cylinder, the cylinder moves end fixedly connected on the filter plate upper end, the slide box front end fixedly connected with the discharge pipe, the cylinder lower end fixedly connected with the water tank, the water tank inside fixedly connected with two net board, two net board inboard all install a plurality of groups of steel wire brush, the water tank is opened and has the drain hole.

2. An apparatus according to claim 1, wherein: The die head is fixedly connected to the discharge pipe, the die head is annular, a through hole is formed in the middle of the die head, a cavity is formed in the die head, an annular opening is arranged in the middle of the die head, the annular opening is communicated with the cavity, and the annular opening is downwardly formed towards the middle.

3. An apparatus according to claim 2, wherein: A shell is fixedly connected in the slide box, an impeller is rotatably connected in the shell, a drain pipe is fixedly connected to the shell, a water inlet pipe is fixedly connected to the lower end of the shell, and the drain pipe extends to the outside of the water tank.

4. An apparatus according to claim 3, wherein: A driving motor is fixedly connected to the cylinder, the transmission screw rod is fixedly connected to the output shaft of the driving motor, a first pulley is fixedly connected to the transmission screw rod, a second pulley is fixedly connected to the impeller, the first pulley and the second pulley are connected through a synchronous belt, and the diameter of the first pulley is three times that of the second pulley.

5. An apparatus according to claim 1, wherein: A feeding hopper is fixedly connected to the upper end of the cylinder, and the feeding hopper is communicated with the inside of the cylinder.

6. An apparatus according to claim 4, wherein: An auxiliary roller is rotatably connected to the water tank, and the middle of the auxiliary roller is inwardly recessed.

7. An apparatus according to claim 6, wherein: A reflux tank is fixedly connected to the lower end of the water tank, the water inlet pipe extends into the reflux tank, and the opening of the water tank is located below the auxiliary roller.

8. An apparatus according to claim 7, wherein: The reflux tank gradually deepens from front to back.

9. An apparatus according to claim 1, wherein: Both the net boards are elastic net boards.

10. Process for processing a cable using the extrusion apparatus of claim 8, characterized in that: The process comprises the following steps: In step one, plastic particles enter the screw extruder through the feeding hopper after being heated and plasticized, are uniformly distributed through the cavity of the die head, and are extruded downward from the annular opening of the die head to wrap the surface of the cable; In step two, the filter plate is driven to descend into the water tank by the cylinder during the wrapping process, the impeller discharges the cold water in the water tank through the drain pipe, simultaneously absorbs new water through the water inlet pipe to form a circulating water flow to impact the surface of the filter plate; In step three, after the wrapped cable enters the water tank, the recessed structure of the auxiliary roller guides the cable to form a 90° corner, the cold water discharged through the drain hole precisely impacts the corner of the cable, the low-temperature water flow is used to rapidly cool the wrapping layer, and the skin cracking caused by thermal stress is eliminated; In step four, the side wall of the recess of the auxiliary roller is in contact with the surface of the cable, the fluid dynamic pressure effect is used to reduce friction and prevent the cable from deviating; In step five, the shaped cable is uniformly wound through the traction device, and the cable arrangement mechanism ensures that the cables are neatly stacked.

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