An injection mold based on a uniform plasticized structure of recycled plastic particles

Abstract

The present invention relates to the field of recycled plastic injection molding technology, and discloses an injection mold based on a uniform plasticizing structure of recycled plastic particles, comprising a molding part, wherein the molding part comprises a fixed mold, and one side of the fixed mold is slidably connected to a movable mold. The injection mold based on the uniform plasticizing structure of recycled plastic particles can effectively solve the problems in the prior art, in which the main purpose of the screw conveyor is to convey, and the recycled plastic particles are conveyed forward and gradually plasticized under the rotation of the screw, but the recycled plastic particles are complex in source, and there are large differences in their materials, shapes and additives contained. It is difficult to fully and evenly mix the recycled plastic particles of different characteristics before entering the mold by relying solely on the conveying and preliminary plasticizing of the screw, and the composition and performance are easily uneven inside the product, the product has insufficient strength in some parts, and is prone to rupture when subjected to external force, the overall quality is poor, and the production efficiency and product qualification rate are low.

Description

Technical Field

[0001] The present invention relates to the technical field of recycled plastic injection molding, and in particular to an injection mold based on a uniform plasticizing structure of recycled plastic particles. Background Art

[0002] Injection molds are tools used to produce plastic products. They inject heated, molten plastic into a mold cavity, where it cools and solidifies to create the finished product. Recycled plastic injection molding is a technology that reprocesses recycled waste plastic into plastic products. This effectively reduces the environmental impact of waste plastic, reduces the amount of plastic waste landfilled and incinerated, and reduces the demand for virgin plastic raw materials.

[0003] In the existing technology, the main purpose of the screw conveyor is transportation. The recycled plastic particles are transported forward and gradually plasticized under the push of the screw's rotation. However, the sources of recycled plastic particles are complex, and there are large differences in their materials, shapes, and additives. It is difficult to fully and evenly mix the recycled plastic particles with different characteristics before entering the mold by relying solely on the screw's transportation and initial plasticization. The product is prone to uneven composition and performance. The product has insufficient strength in some parts and is prone to rupture when subjected to external force. The overall quality is low, which reduces production efficiency and product qualification rate. Summary of the Invention

[0004] In response to the above-mentioned shortcomings of the prior art, the present invention provides an injection mold based on a uniform plasticizing structure for recycled plastic particles, which can effectively solve the problems in the prior art where the main purpose of the screw conveyor is transportation, and the recycled plastic particles are transported forward and gradually plasticized under the rotation of the screw. However, the sources of recycled plastic particles are complex, and there are large differences in their materials, shapes, and additives. It is difficult to fully and evenly mix recycled plastic particles with different characteristics before entering the mold by relying solely on the conveying and preliminary plasticizing of the screw. The product is prone to uneven composition and performance, and the product has insufficient strength in some parts, and is prone to rupture when subjected to external force, resulting in poor overall quality, low production efficiency, and low product qualification rate.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0006] The present invention provides an injection mold based on a uniform plasticizing structure of recycled plastic particles, comprising:

[0007] A forming part, the forming part includes a fixed mold, one side of the fixed mold is slidably connected to the movable mold, and a side of the fixed mold away from the movable mold is fixedly connected to the heat insulation board;

[0008] The conveying part includes a barrel fixedly connected to one side of the driving seat, a screw connected to the interior of the driving seat is provided inside the barrel, and the screw is connected to a guide head through a threaded rod connected to the outer end of the screw;

[0009] A transition tube, the transition tube being detachably connected to a side of the heat insulation plate away from the movable mold, the side of the transition tube away from the movable mold being detachably connected to the outer end of the barrel, and the interior of the transition tube being provided with a mixing element for mixing external plastic;

[0010] In which, the mixing element includes a connecting ring plate, which is connected to the circumferential outer surface of the guide head through a connecting piece arranged inside it. The interior of the connecting ring plate is slidably connected to a stirring column, and the end of the stirring column away from the connecting ring plate is fixedly connected to a connecting plate that fits into the inner wall of the transition cylinder.

[0011] Furthermore, the connecting part includes a limiting ring plate, which is fixedly connected to the side of the connecting ring plate close to the stirring column, and the side of the connecting ring plate away from the stirring column is fixedly connected to the limiting plate. There are four limiting plates in a circular array with the screw as the center, and a limiting groove is provided on the circumferential outer surface of the guide head. The side of the guide head away from the stirring column is fixedly connected to a limiting block that fits with the outer surface of the limiting plate.

[0012] Furthermore, a washer that fits the outer end of the screw rod is sleeved on the circumferential outer surface of the threaded rod, and a check ring that slides with the circumferential outer surface of the threaded rod is provided on the side of the washer away from the screw rod.

[0013] Furthermore, a pad bead that fits the inner circumferential wall of the check ring is fixedly connected to the outer circumferential surface of the threaded rod. There are multiple pad beads arranged in a circumferential array with the threaded rod as the center, and a through groove is opened inside the guide head.

[0014] Furthermore, a folding ring plate is fixedly connected to the circumferential outer surface of the check ring, and the side of the folding ring plate away from the fixed mold is fitted with the outer end of the barrel. A groove is provided on the side of the connecting ring plate away from the stirring column, and the inner wall surface of the groove is fitted and slid with the outer surface of the folding ring plate.

[0015] Furthermore, the outer surface of the transition tube is provided with a heating ring, the outer surface of the barrel is provided with a heating sleeve, one end of the transition tube is connected to the outer end flange of the barrel through a flange plate, and the other end of the transition tube is connected to the outer surface flange of the insulation board through a flange plate.

[0016] Furthermore, a swivel is rotatably connected to the inner wall surface of the transition cylinder, a fixing column is fixedly connected to the outer surface of the swivel, and a side of the fixing column away from the swivel is designed with an arc surface.

[0017] Furthermore, the diameter of the screw is designed to be gradual, and the end with the largest diameter of the screw is close to the side of the guide head.

[0018] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0019] The present invention is provided with a transition barrel, a mixing piece and a connecting piece. When the driving group drives the screw to rotate, the guide head drives the mixing piece to rotate inside the transition barrel through the connecting piece. The plastic particles enter the interior of the transition barrel after preliminary stirring during transportation. The stirring column continuously rotates and stirs inside the transition barrel, which can effectively mix plastic particles with large differences in material, shape and additives, avoids the phenomenon of "stratification", "mottling" or "cold spots" of plastic particles with different densities and melting points, and interrupts the filling of molds, further prevents the uneven composition of the recycled plastic products, avoids the situation of insufficient strength of injection molded products, improves the overall quality of plastic products, and greatly improves production efficiency and product qualification rate. After being fully mixed by the mixing piece, the properties of the new plastic and the waste plastic are averaged through physical mixing, and the performance fluctuations of the waste plastic are dispersed throughout the system, avoiding local performance defects that lead to product defects, thereby allowing a higher proportion of waste materials to be used, reducing the use of new material particles, and improving the reuse rate of waste plastic particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0021] Figure 1 A schematic diagram of the three-dimensional structure of an embodiment of the present invention;

[0022] Figure 2 Schematic diagram of the cross-sectional structure of the heat insulation board according to an embodiment of the present invention;

[0023] Figure 3 For the embodiment of the present invention Figure 2 A schematic diagram of the partially enlarged structure at center A;

[0024] Figure 4 This is a schematic structural diagram of the screw, mixing element and fixed column according to an embodiment of the present invention;

[0025] Figure 5 Schematic diagram of the separation structure of the screw, threaded rod, connecting ring plate and check ring according to an embodiment of the present invention;

[0026] Figure 6This is a structural diagram of a threaded rod, a guide head, and a connecting ring plate according to an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the state change structure of the check ring and the gasket according to an embodiment of the present invention;

[0028] Figure 8 For the embodiment of the present invention Figure 7 A schematic diagram of the structure with a partial enlargement at point B in the middle;

[0029] Figure 9 Schematic diagram of the separation structure of the guide head and the connecting ring plate according to an embodiment of the present invention.

[0030] The numbers in the figure represent: 1. Forming part; 11. Fixed mold; 12. Moving mold; 13. Heat insulation board; 2. Conveying part; 21. Barrel; 211. Heating jacket; 22. Screw; 23. Threaded rod; 231. Bead; 24. Guide head; 25. Washer; 26. Check ring; 261. Folding ring plate; 3. Transition cylinder; 31. Mixing part; 311. Connecting ring plate; 3111. Slot; 312. Stirring column; 313. Connecting plate; 32. Connecting part; 321. Limiting ring plate; 322. Limiting plate; 323. Limiting groove; 324. Limiting block; 33. Heating ring; 34. Rotating ring; 341. Fixed column. DETAILED DESCRIPTION

[0031] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] The present invention will be further described below with reference to the embodiments.

[0033] Example:

[0034] See also Figures 1-9 The present invention provides a technical solution: an injection mold based on a uniform plasticizing structure of recycled plastic particles, comprising:

[0035] The forming part 1 includes a fixed mold 11, a movable mold 12 is slidably connected to one side of the fixed mold 11, and a heat insulation board 13 is fixedly connected to the side of the fixed mold 11 away from the movable mold 12;

[0036] The conveying part 2 includes a barrel 21 fixedly connected to one side of the driving seat. A screw 22 connected to the inside of the driving seat is provided inside the barrel 21. The screw 22 is connected to a guide head 24 through a threaded rod 23 connected to the outer end thereof.

[0037] The transition tube 3 is detachably connected to the side of the heat insulation plate 13 away from the movable mold 12. The side of the transition tube 3 away from the movable mold 12 is detachably connected to the outer end of the barrel 21. The interior of the transition tube 3 is provided with a mixing element 31 for mixing external plastics;

[0038] Among them, the mixing element 31 includes a connecting ring plate 311, which is connected to the circumferential outer surface of the guide head 24 through a connecting piece 32 arranged inside it. The interior of the connecting ring plate 311 is slidingly connected to a stirring column 312, and the end of the stirring column 312 away from the connecting ring plate 311 is fixedly connected to a connecting plate 313 that fits the inner wall of the transition cylinder 3.

[0039] The connecting member 32 includes a limiting ring plate 321, which is fixedly connected to the side of the connecting ring plate 311 close to the stirring column 312, and the side of the connecting ring plate 311 away from the stirring column 312 is fixedly connected to the limiting plate 322. There are four limiting plates 322 in a circular array with the screw 22 as the center. A limiting groove 323 is provided on the circumferential outer surface of the guide head 24, and a limiting block 324 is fixedly connected to the side of the guide head 24 away from the stirring column 312, which fits the outer surface of the limiting plate 322.

[0040] The outer circumferential surface of the threaded rod 23 is sleeved with a washer 25 that fits with the outer end of the screw rod 22 , and a check ring 26 that slides with the outer circumferential surface of the threaded rod 23 is provided on the side of the washer 25 away from the screw rod 22 .

[0041] The outer circumferential surface of the threaded rod 23 is fixedly connected with a pad bead 231 that fits the inner circumferential wall of the check ring 26. There are multiple pad beads 231 arranged in a circumferential array with the threaded rod 23 as the center, and a through groove is opened inside the guide head 24.

[0042] The circumferential outer surface of the check ring 26 is fixedly connected to a folding ring plate 261, and the side of the folding ring plate 261 away from the fixed mold 11 is in contact with the outer end of the barrel 21. A groove 3111 is provided on the side of the connecting ring plate 311 away from the stirring column 312, and the inner wall surface of the groove 3111 is in contact with the outer surface of the folding ring plate 261 and slides.

[0043] The outer surface of the transition tube 3 is provided with a heating ring 33, and the outer surface of the barrel 21 is provided with a heating sleeve 211. One end of the transition tube 3 is flange-connected to the outer end of the barrel 21 through a flange, and the other end of the transition tube 3 is flange-connected to the outer surface of the insulation plate 13 through a flange.

[0044] A swivel 34 is rotatably connected to the inner wall surface of the transition barrel 3, and a fixing post 341 is fixedly connected to the outer surface of the swivel 34. The side of the fixing post 341 away from the swivel 34 is designed with a curved surface. When the mixing element 31 stirs inside the transition barrel 3, the fixing post 341 will not collide with the guide head 24.

[0045] The diameter of the screw rod 22 is designed to be gradual, and the end of the screw rod 22 with the largest diameter is close to the side of the guide head 24.

[0046] The process of mixing plastic particles:

[0047] The upper position of the outer surface of the circumference of the barrel 21 is fixedly connected to a hopper, and the recycled plastic particles are added from the hopper to the inside of the barrel 21, and the driving seat is started. The driving seat drives the screw 22 to rotate clockwise in the barrel 21, and the plastic particles are moved to the side of the movable mold 12 through the spiral blades on the outer surface of the circumference of the screw 22. The diameter of the screw 22 adopts a gradually thickening design. The diameter of the end of the screw 22 close to the driving seat is smaller, and the cavity formed by the outer surface of the screw 22 and the inner wall surface of the barrel 21 is larger, so that the plastic particles can fall smoothly and avoid jamming during loading; the diameter of the end of the screw 22 close to the guide head 24 is larger, and the cavity formed by the outer surface of the screw 22 and the inner wall surface of the barrel 21 is smaller. During the conveying process, the plastic particles can be moved to the inner wall of the circumference of the barrel 21, so that the plastic particles are closer to the heating sleeve 211 sleeved on the outer surface, and the temperature there is higher, which accelerates the melting of the plastic particles.

[0048] The plastic particles, gradually turning into a liquid state, are moved toward the transition barrel 3 by screw 22. Driven by the material, the end of check ring 26 near the fixed mold 11 abuts against the outer surface of guide head 24, leaving a gap between check ring 26 and gasket 25. Check ring 26 and folding plate 261 are integrally designed. The side of folding plate 261 near the fixed mold 11 enters the interior of groove 3111, and the inner wall of groove 3111 completely abuts the outer surface of folding plate 261. The material flows from the outer surface of gasket 25 into the cavity enclosed by the inner circumference of barrel 21 and continues forward (between the fixed mold 11 and movable mold 12). The material passes through the gap between check ring 26 and threaded rod 23 and flows into the interior of transition barrel 3 through the through-slot defined within guide head 24. Four through slots are formed inside the guide head 24 , and four limiting slots 323 are formed on the circumferential outer surface of the guide head 24 . The limiting slots 323 are staggered with the through slots, and the angle between the limiting slots 323 and the through slots is forty-five degrees.

[0049] Four pad beads 231 are fixedly connected to the outer surface of the threaded rod 23. Under the action of the pad beads 231, the central axis of the check ring 26 can always coincide with the central axis of the threaded rod 23, and the contact area between the outer surface of the pad beads 231 and the circumferential inner wall of the check ring 26 is small, which does not hinder the inflow of plastic and can ensure that the check ring 26 can slide smoothly on the outer surface of the threaded rod 23 in different states.

[0050] While loading the material, the guide head 24 also drives the mixing element 31 to stir the interior of the transition barrel 3. The guide head 24 is embedded in the inner circumferential surface of the limiting ring plate 321. The side of the guide head 24 close to the fixed mold 11 is closely attached to the limiting ring plate 321, and the side of the guide head 24 away from the fixed mold 11 is attached to the inner surface of the limiting plate 322. The guide head 24 is located between the limiting ring plate 321 and the limiting plate 322. When the screw 22 rotates clockwise as a whole (when the screw 22 rotates clockwise, the connection between the screw 22 and the threaded rod 23 becomes tighter), the outer surface of the limit block 324 in the clockwise direction of rotation fits in with the outer surface of the limit plate 322 (the outer surface of the limit block 324 adopts a curved surface design that fits in with the outer surface of the limit plate 322). The limit plate 322 and the limit ring plate 321 adopt an integrated structure, and the connecting ring plate 311 rotates clockwise synchronously through the transmission of the limit plate 322 and the limit block 324. The interior of the connecting ring plate 311 is penetrated by a stirring column 312, and the other end of the stirring column 312 is connected to the connecting plate 313. The connecting plate 313 and the connecting ring plate 311 form a whole under the action of the stirring column 312, and rotate clockwise synchronously inside the transition barrel 3, stirring the material inside the transition barrel 3 and further plasticizing it under the action of the heating ring 33 on the outer surface of the transition barrel 3.

[0051] The transition tube 3 comprises a straight portion and a nozzle, which extends to the gate of the fixed mold 11. The two are internally connected. A swivel 34 is rotatably connected to the inner wall of the nozzle. The swivel 34 can rotate approximately 90 degrees within the transition tube 3. When the fixed post 341 on the outer surface of the swivel 34 is fixed to the material, it rotates synchronously.

[0052] The rotation of the mixing element 31 within the transition barrel 3 causes the plasticized plastic inside to form a circular flow, creating a specific flow state within the transition barrel 3. The flowing plastic is pushed outward clockwise from the vicinity of the stirring column 312, then flows downward or upward along the inner wall of the transition barrel 3, and then returns to the vicinity of the stirring column 312 from the bottom or top of the transition barrel 3, forming a circular flow. During this process, the flow of material generates a flexible thrust on the rotating ring 34 and fixed column 341, driving them to rotate clockwise along with the liquid material until the rotating ring 34 as a whole reaches its maximum rotation range and can no longer move. The rotating ring 34 and fixed column 341 no longer rotate and are in a relative static state with the transition barrel 3.

[0053] At this point, the fixed column 341 remains stationary, while the stirring column 312 continuously rotates in tandem with the screw 22, creating a complex flow field for the plasticized liquid within the transition barrel 3. The rotation of the stirring column 312 drives the surrounding plastic into motion, forming a mainstream region. Relatively static or slower flow regions form around the fixed column 341. Velocity differences and shear forces between the mainstream region and these regions create a flow, forcing the plasticized liquid to flow between these different velocity regions, increasing the chances of mixing. This complex flow field prevents simple, monolithic particle flow, allowing particles at different locations to fully participate in mixing and improving mixing uniformity. The clockwise rotation of the stirring column 312 exerts a shearing effect on the plasticized liquid, breaking it up and causing friction and collision between different plastics. Simultaneously, a boundary layer forms near the surface of the stationary fixed column 341, further increasing the shear forces experienced by the plastics as they pass through this boundary layer. This shearing effect helps break up plastic agglomerates, allowing recycled plastics of different types and properties to more fully contact and mix, thereby improving mixing quality and resulting in more stable final product performance. During this process, even if there are unmelted plastic particles inside, the stirring action of the mixing element 31 can fully mix them and complete the plasticization.

[0054] Injection molding process:

[0055] After the material inside the transition barrel 3 is evenly mixed, the screw 22 stops rotating, and the drive seat drives the screw 22 toward the fixed die 11. The guide head 24 and the threaded rod 23 move synchronously. The connecting plate 313 on the outer surface of the guide head 24 forms a single unit with the guide head 24 via the retaining ring plate 321, and the connecting plate 313 also moves toward the fixed die 11. During this process, although the screw 22 stops rotating for a short period of time, the plasticized liquid inside still has a certain amount of inertia. When it collides with the stopped screw 22, it generates a certain reverse force. The plasticized liquid drives the rotating ring 34 to generate a small, counterclockwise rotational force. As the guide head 24 moves forward, the outer end of the curved surface of the fixing post 341 contacts the guide head 24 between two adjacent through-slots and stops, resting inside the through-slots of the guide head 24 (the through-slots form a relatively concave area on the outer surface of the guide head 24). As the guide head 24 continues to move, the fixing post 341 follows the direction of the through-slots and passes through the guide head 24 and enters the interior of the check ring 26. The threaded rod 23 and the guide head 24 adopt an integrated structural design. There are four pad beads 231 and four through grooves. The pad beads 231 and the through grooves are staggered to prevent the fixing column 341 from entering the check ring 26 and colliding with the pad beads 231.

[0056] As the screw 22 advances, the pressure inside the transition barrel 3 is high, causing the check ring 26 to slide along the outer circumferential surface of the threaded rod 23 toward the side away from the fixed die 11. At this time, the outer surface of the folding plate 261 near the fixed die 11 separates from the inner wall of the retaining groove 3111, but a portion of the folding plate 261 remains within the retaining groove 3111. The end of the check ring 26 away from the fixed die 11 is designed with a conical surface that mates with the outer surface of the gasket 25. Under the pressure inside the transition barrel 3, the conical surface of the check ring 26 and the conical surface of the gasket 25 are completely and tightly fitted, preventing the plasticized liquid from flowing back into the barrel 21.

[0057] During this process, the plasticized liquid originally in the interior of the transition barrel 3 is injected into the gate at the outer end of the fixed mold 11 through the nozzle, and then enters the cavity between the fixed mold 11 and the movable mold 12. The coolant inside the mold accelerates the cooling of the plasticized liquid. After cooling and molding, the fixed mold 11 moves to the side away from the fixed mold 11 under the action of the external demoulding equipment, and the molded product is ejected through the internal ejection equipment to complete the unloading action. When the molding part 1 is unloading, the screw 22 retracts backward, the guide head 24 retracts synchronously, and the connecting ring plate 311 fits with the outer surface of the limit block 324 through the limit plate 322, and retracts synchronously to the initial position under the action of the guide head 24. Repeat the loading steps to transport the plasticized plastic particles to the interior of the transition barrel 3, so that different types of plastics are fully integrated to avoid stratification, uneven color, and incomplete plasticization.

[0058] The process of disassembling the transition barrel 3 and the outer end of the barrel 21:

[0059] When regular cleaning or maintenance is required, the screw 22 is driven by the drive seat to rotate in the opposite direction for a certain angle, then the machine is stopped and the heating ring 33 is removed. When the screw 22 rotates in the opposite direction, the guide head 24 rotates in the opposite direction along with it until the counterclockwise outer surface of the limit block 324 fits into the arc surface of another limit plate 322. At this time, the limit groove 323 on the outer surface of the guide head 24 coincides with the position of the limit plate 322 on the outer surface of the connecting ring plate 311, and the area occupied by the limit groove 323 is larger than the area of the limit plate 322. Find the bolts connecting the transition barrel 3 and the outer end flange of the barrel 21. These bolts are evenly distributed on the circumference of the flange. Use a suitable wrench to loosen the bolts one by one in diagonal order. Loosen each bolt a few turns first, and then gradually unscrew them completely. This can avoid deformation or damage to the flange due to uneven force.

[0060] After all bolts are removed, gently pry the flanges on the outer ends of the transition barrel 3 and barrel 21, gradually separating them axially. After separation, the transition barrel 3 contains the mixing element 31, rotating ring 34, and fixed column 341, while the barrel 21 contains the guide head 24, washer 25, threaded rod 23, check ring 26, and screw 22. The transition barrel 3 and barrel 21 are now completely separated, allowing cleaning or maintenance of any remaining plastic inside. Similarly, the end of the barrel 21 closest to the fixed mold 11 is also connected to the heat shield 13 via a flange.

[0061] In summary, the injection mold device has the following advantages:

[0062] Advantage 1: When the screw 22 rotates, the connecting piece 32 drives the mixing piece 31 to rotate inside the transition barrel 3. The plastic particles enter the interior of the transition barrel 3 after preliminary stirring during transportation. The stirring column 312 continuously rotates and stirs inside the transition barrel 3, which can effectively mix the plastic particles with large differences in material, shape and additives, avoids the phenomenon of "stratification", "mottling" or "cold spots" of plastic particles with different densities and melting points, further prevents the uneven composition of the recycled plastic products, avoids the situation of insufficient strength of injection molded products, and thus improves the overall quality of injection molded products. At the same time, the production efficiency and product qualification rate will also be greatly improved.

[0063] Advantage 2: Waste plastic particles vary in their origin, degree of aging, and contamination, leading to varying properties (such as molecular weight, strength, and melting point). After thorough mixing in the mixing element 31, the properties of the new and waste plastics are physically averaged, dispersing fluctuations in the waste plastic's properties throughout the system. This prevents product defects caused by localized performance differences, allowing for a higher proportion of waste material to be used, reducing the use of new material particles and increasing the reuse rate of waste plastic particles. Furthermore, after thorough mixing, the overall fluidity of the material becomes more uniform, allowing for smoother filling of the plastic into the fixed and movable molds 11 and 12 during injection molding. This reduces resistance during the injection molding process and mitigates problems such as material shortages and short shots caused by localized poor fluidity.

[0064] Advantage three: waste plastics will absorb moisture (such as if they are not completely dried after cleaning), residual detergents, oil or other pollutants during the recycling process. The evaporation of moisture or the decomposition of impurities at high temperatures will release gas. The transition cylinder 3 can provide a temporary residence space for the plasticized plastic particles. While the mixing element 31 is stirring, it can help to discharge the gas in the plasticized waste recycled plastic, reduce the doping of bubbles inside the plasticized liquid, avoid problems such as pores on the surface of the product, internal voids, silver streaks, etc. caused by residual gas, improve the qualified rate of finished products, reduce the injection pressure fluctuations caused by gas accumulation, and ensure the filling stability.

[0065] Advantage 4: The diameter of the screw 22 is designed to gradually increase, allowing for accelerated melting due to gradient heating. The end closest to the drive seat has a smaller diameter, creating a larger cavity with the inner wall of the barrel 21. This facilitates the smooth fall of plastic pellets, effectively avoiding jamming during loading, ensuring smooth loading, and improving work efficiency. The end of the screw 22 closest to the guide head 24 has a larger diameter, creating a smaller cavity with the inner wall of the barrel 21. This allows the plastic pellets to be moved toward the inner circumference of the barrel 21, bringing them closer to the heating jacket 211. This allows for accelerated melting of the plastic pellets at a higher temperature, shortening the plasticizing time and improving production efficiency.

[0066] Advantage 5: Fixed column 341 remains stationary while stirring column 312 rotates continuously. The relative motion of the two creates a complex flow field for the plasticized liquid within transition barrel 3. A velocity difference and shear force are created between the mainstream area and the relatively stationary or slow-flowing areas around fixed column 341. This increases the mixing opportunities for the plasticized liquid, prevents simple bulk flow of particles, and improves mixing uniformity. The clockwise rotation of stirring column 312 shears the plasticized liquid, breaking it up and causing different plastics to rub and collide with each other. Simultaneously, the boundary layer near the surface of fixed column 341 further increases the shear force, helping to break up plastic agglomerations and allowing recycled plastics of different types and properties to fully contact and mix, improving mixing quality and ensuring stable performance of the final product.

[0067] Advantage 6. Recycled plastic particles may contain impurities, moisture or carbonized residues. The detachable structure of the transition barrel 3 allows the operator to quickly disassemble the internal components and thoroughly remove the residual plastic melt, avoiding mixed contamination of different batches of raw materials and reducing product defects caused by impurities. The detachable structure of the transition barrel 3 provides a more open operating area. The operator can complete maintenance without having to touch high-temperature and high-pressure components, reducing the risk of burns and mechanical injuries. The disassembly angle is more ergonomic, reducing the operator's labor intensity and improving operating comfort. When injection molding new materials, the transition barrel 3 can be removed, and the heat insulation plate 13 can be connected to the outer end of the barrel 21 through a flange. For the remanufacturing of plastic recycled particles, the transition barrel 3 is used, and the mixing element 31 is used to fully mix the recycled plastic particles.

[0068] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An injection mold based on a uniform plasticized structure of recycled plastic particles, characterized in that: include: A molding part (1), the molding part (1) comprising a fixed mold (11), one side of the fixed mold (11) being slidably connected to a movable mold (12), and a side of the fixed mold (11) away from the movable mold (12) being fixedly connected to a heat insulation plate (13); A conveying portion (2), the conveying portion (2) comprising a barrel (21) fixedly connected to one side of a driving seat, a screw (22) connected to the interior of the driving seat being provided inside the barrel (21), and the screw (22) being connected to a guide head (24) via a threaded rod (23) connected to the outer end thereof; A transition tube (3), the transition tube (3) being detachably connected to a side of the heat insulation plate (13) away from the movable mold (12), the side of the transition tube (3) away from the movable mold (12) being detachably connected to the outer end of the barrel (21), and a mixing element (31) for mixing external plastics being provided inside the transition tube (3); The mixing element (31) includes a connecting ring plate (311), the connecting ring plate (311) is connected to the outer circumferential surface of the guide head (24) via a connecting piece (32) provided therein, a stirring column (312) is slidably connected to the interior of the connecting ring plate (311), and one end of the stirring column (312) away from the connecting ring plate (311) is fixedly connected to a connecting plate (313) that is in contact with the inner wall of the transition cylinder (3); The connecting member (32) includes a limiting ring plate (321), the limiting ring plate (321) is fixedly connected to the side of the connecting ring plate (311) close to the stirring column (312), the side of the connecting ring plate (311) away from the stirring column (312) is fixedly connected to the limiting plate (322), the limiting plates (322) are arranged in a circular array with the screw (22) as the center, the limiting groove (323) is provided on the circumferential outer surface of the guide head (24), the side of the guide head (24) away from the stirring column (312) is fixedly connected to a limiting block (324) that fits the outer surface of the limiting plate (322), the threaded rod ( The outer circumferential surface of the threaded rod (23) is sleeved with a washer (25) that fits with the outer end of the screw rod (22), and a non-return ring (26) that slides with the outer circumferential surface of the threaded rod (23) is provided on the side of the washer (25) away from the screw rod (22), and the outer circumferential surface of the threaded rod (23) is fixedly connected with a cushion bead (231) that fits with the inner circumferential wall of the non-return ring (26), and a plurality of cushion beads (231) are arranged in a circumferential array with the threaded rod (23) as the center. A through groove is provided inside the guide head (24), and the diameter of the screw rod (22) adopts a gradual design, and the end with the largest diameter of the screw rod (22) is close to the side of the guide head (24).

2. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 1, characterized in that: A folding plate (261) is fixedly connected to the circumferential outer surface of the check ring (26), and a side of the folding plate (261) away from the fixed mold (11) is in contact with the outer end of the barrel (21). A slot (3111) is provided on a side of the connecting ring plate (311) away from the stirring column (312), and an inner wall surface of the slot (3111) is in contact and slides with the outer surface of the folding plate (261).

3. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 2, characterized in that: The outer surface of the transition tube (3) is provided with a heating ring (33), the outer surface of the barrel (21) is provided with a heating sleeve (211), one end of the transition tube (3) is flange-connected to the outer end of the barrel (21) via a flange, and the other end of the transition tube (3) is flange-connected to the outer surface of the heat insulation plate (13) via a flange.

4. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 3, characterized in that: The inner wall surface of the transition cylinder (3) is rotatably connected to a rotating ring (34), and the outer surface of the rotating ring (34) is fixedly connected to a fixing column (341). The side of the fixing column (341) away from the rotating ring (34) adopts a curved surface design.

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