Injection mold based on plastic recovery particle uniform plasticizing structure

Abstract

The invention relates to the technical field of recycled plastic injection molding, and discloses an injection mold based on a plastic recycled particle uniform plasticizing structure, the injection mold comprises a molding part, the molding part comprises a fixed mold, and one side of the fixed mold is slidably connected with a movable mold. The injection mold based on the uniform plasticizing structure of the plastic recycled particles can effectively solve the problems that in the prior art, the main purpose of a spiral conveyor is conveying, the recycled plastic particles are conveyed forwards and plasticized step by step under rotation pushing of a screw, but the recycled plastic particles are complex in source and difficult to plasticize. The material, the shape, the contained additives and the like of the recycled plastic particles are greatly different, the recycled plastic particles with different characteristics are difficult to be fully and uniformly mixed when entering a mold only through screw conveying and preliminary plasticizing, the interiors of products are easy to have nonuniform components and performances, and the strength of some parts of the products is insufficient. The invention solves the problems of high probability of breakage when bearing external force, poor overall quality, low production efficiency and low product percent of pass.

Description

Technical Field

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

[0002] An injection mold is a tool for producing plastic products. It injects heated and molten plastic into the mold cavity and obtains finished products after cooling and solidification. Recycled plastic injection molding is a technology that reprocesses recycled waste plastics into plastic products, which can effectively reduce the environmental pollution caused by waste plastics, reduce the amount of plastic waste landfilled and incinerated, and at the same time reduce the demand for virgin plastic raw materials.

[0003] In the prior art, the main purpose of a screw conveyor is to convey. Under the rotation of the screw, recycled plastic particles are pushed forward for conveying and gradually plasticized. However, the sources of recycled plastic particles are complex, and there are significant differences in their materials, shapes, and additives. It is difficult to fully and evenly mix different characteristic plastic recycling particles before entering the mold only by the conveying and preliminary plasticization of the screw. The internal components and properties of the product are prone to unevenness, and the product has insufficient strength in some parts, is prone to cracking when subjected to external forces, has poor overall quality, and reduces production efficiency and product qualification rate. Summary of the Invention

[0004] Aiming at the above-mentioned disadvantages of the prior art, the present invention provides an injection mold based on a uniform plasticizing structure of plastic recycling particles, which can effectively solve the problems in the prior art that the main purpose of a screw conveyor is to convey, under the rotation of the screw, recycled plastic particles are pushed forward for conveying and gradually plasticized, but the sources of recycled plastic particles are complex, there are significant differences in their materials, shapes, and additives, it is difficult to fully and evenly mix different characteristic plastic recycling particles before entering the mold, the internal components and properties of the product are prone to unevenness, the product has insufficient strength in some parts, is prone to cracking when subjected to external forces, has poor overall quality, and low production efficiency and product qualification rate.

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

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

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

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

[0009] The transition cylinder, the transition cylinder is detachably connected to the side of the heat insulation plate away from the moving mold, the side of the transition cylinder away from the moving mold is detachably connected to the outer end of the barrel, and a mixing part for mixing external plastics is arranged inside the transition cylinder;

[0010] Among them, the mixing part includes a connecting ring plate, the connecting ring plate is connected to the circumferential outer surface of the guiding head through a connecting part arranged inside it, a stirring column is slidably connected inside the connecting ring plate, and one end of the stirring column away from the connecting ring plate is fixedly connected with a connecting plate that fits the inner wall of the transition cylinder.

[0011] Further, the connecting part includes a limiting ring plate, the limiting ring plate is fixedly connected to the side of the connecting ring plate close to the stirring column, a limiting plate is fixedly connected to the side of the connecting ring plate away from the stirring column, there are four limiting plates arranged in a circumferential array with the screw rod as the center, a limiting groove is opened on the circumferential outer surface of the guiding head, and a limiting block that fits the outer surface of the limiting plate is fixedly connected to the side of the guiding head away from the stirring column.

[0012] Further, a washer that fits the outer end of the screw rod is sleeved on the circumferential outer surface of the threaded rod, and a non-return ring that slides on the circumferential outer surface of the threaded rod is arranged on the side of the washer away from the screw rod.

[0013] Further, a cushion bead that fits the circumferential inner wall of the non-return ring is fixedly connected to the circumferential outer surface of the threaded rod, a plurality of cushion beads are arranged in a circumferential array with the threaded rod as the center, and a through groove is opened inside the guiding head.

[0014] Further, a folding ring plate is fixedly connected to the circumferential outer surface of the non-return ring, the side of the folding ring plate away from the fixed mold fits the outer end of the barrel, a clamping groove is opened on the side of the connecting ring plate away from the stirring column, and the inner wall surface of the clamping groove fits and slides with the outer surface of the folding ring plate.

[0015] Further, a heating ring is sleeved on the outer surface of the transition cylinder, a heating sleeve is sleeved on the outer surface of the barrel, one end of the transition cylinder is flange-connected to the outer end of the barrel through a flange, and the other end of the transition cylinder is flange-connected to the outer surface of the heat insulation plate through a flange.

[0016] Further, a rotating ring is rotatably connected to the inner wall surface of the transition cylinder, a fixing column is fixedly connected to the outer surface of the rotating ring, and the side of the fixing column away from the rotating ring is designed with a cambered surface.

[0017] Furthermore, the diameter of the screw rod is designed in a gradual change manner, and the largest diameter end of the screw rod is close to the side of the guiding head.

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

[0019] The present invention is provided with a transition cylinder, a mixing member and a connecting member. When the driving group drives the screw rod to rotate, the guiding head drives the mixing member to rotate inside the transition cylinder through the connecting member. After the plastic particles are preliminarily stirred during the transportation process, they enter the inside of the transition cylinder. Through the continuous rotation and stirring of the stirring column inside the transition cylinder, plastic particles with large differences in material, shape, additives, etc. can be effectively mixed, avoiding the phenomena of "stratification", "mottling" or "cold spots" of plastic particles with different densities and melting points, preventing the interruption of mold filling, further preventing uneven composition inside the recycled plastic products, avoiding the situation of insufficient strength of the injection-molded products, improving the overall quality of the plastic products, and at the same time greatly improving the production efficiency and product qualification rate. After being fully mixed by the mixing member, the performance of the new plastic and the waste plastic is averaged through physical mixing, and the performance fluctuations of the waste plastic are dispersed into the whole system, avoiding product defects caused by too poor local performance, thereby allowing a higher proportion of waste materials to be used, reducing the use of new material particles, and improving the recycling rate of waste plastic particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

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

[0022] Figure 2 is a cross-sectional structure schematic diagram of the heat insulation board of an embodiment of the present invention;

[0023] Figure 3 is an embodiment of the present invention Figure 2 is a partial enlarged structure schematic diagram of part A in the embodiment;

[0024] Figure 4 is a structure schematic diagram of the screw rod, the mixing member and the fixing column of an embodiment of the present invention;

[0025] Figure 5 is a separated structure schematic diagram of the screw rod, the threaded rod, the connecting ring plate and the check ring of an embodiment of the present invention;

[0026] Figure 6Schematic structural diagram of the threaded rod, guide head and connecting ring plate in the embodiment of the present invention;

[0027] Figure 7 Schematic structural diagram of the state change of the check ring and washer in the embodiment of the present invention;

[0028] Figure 8 In the embodiment of the present invention Figure 7 Schematic diagram of the partial enlargement at position B in;

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

[0030] The reference numerals in the figure respectively represent: 1, forming part; 11, fixed mold; 12, moving mold; 13, heat insulation plate; 2, conveying part; 21, barrel; 211, heating sleeve; 22, screw; 23, threaded rod; 231, cushion bead; 24, guide head; 25, washer; 26, check ring; 261, folded ring plate; 3, transition cylinder; 31, mixing part; 311, connecting ring plate; 3111, clamping groove; 312, stirring column; 313, connecting plate; 32, connecting piece; 321, limiting ring plate; 322, limiting plate; 323, limiting groove; 324, limiting block; 33, heating ring; 34, rotating ring; 341, fixing column. Detailed implementation manners

[0031] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

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

[0033] Embodiment:

[0034] Please refer to Figures 1-9 , the present invention provides a technical solution: an injection mold based on a uniform plasticization structure of plastic recycling particles, including:

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

[0036] A conveying part 2, the conveying part 2 includes a barrel 21 fixedly connected to one side of the driving seat, a screw 22 is arranged inside the barrel 21 and is connected to the inside of the driving seat, and the screw 22 is connected to a guide head 24 through a threaded rod 23 connected to its outer end;

[0037] The transition cylinder 3 is detachably connected to the side of the heat insulation plate 13 away from the moving mold 12. The side of the transition cylinder 3 away from the moving mold 12 is detachably connected to the outer end of the barrel 21. A mixing member 31 for mixing external plastics is provided inside the transition cylinder 3;

[0038] Among them, the mixing member 31 includes a connecting ring plate 311. The connecting ring plate 311 is connected to the circumferential outer surface of the guiding head 24 through a connecting member 32 provided inside it. A stirring column 312 is slidably connected inside the connecting ring plate 311. One end of the stirring column 312 away from the connecting ring plate 311 is fixedly connected to a connecting plate 313 that fits against the inner wall of the transition cylinder 3.

[0039] 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. A limiting plate 322 is fixedly connected to the side of the connecting ring plate 311 away from the stirring column 312. Four limiting plates 322 are circumferentially arranged around the screw rod 22. A limiting groove 323 is formed on the circumferential outer surface of the guiding head 24. A limiting block 324 that fits against the outer surface of the limiting plate 322 is fixedly connected to the side of the guiding head 24 away from the stirring column 312.

[0040] A washer 25 that fits against the outer end of the screw rod 22 is sleeved on the circumferential outer surface of the threaded rod 23. A non-return ring 26 that slides on the circumferential outer surface of the threaded rod 23 is provided on the side of the washer 25 away from the screw rod 22.

[0041] Pad beads 231 that fit against the circumferential inner wall of the non-return ring 26 are fixedly connected to the circumferential outer surface of the threaded rod 23. A plurality of pad beads 231 are circumferentially arranged around the threaded rod 23. A through groove is formed inside the guiding head 24.

[0042] A folding ring plate 261 is fixedly connected to the circumferential outer surface of the non-return ring 26. The side of the folding ring plate 261 away from the fixed mold 11 fits against the outer end of the barrel 21. A clamping groove 3111 is formed on the side of the connecting ring plate 311 away from the stirring column 312. The inner wall surface of the clamping groove 3111 fits and slides against the outer surface of the folding ring plate 261.

[0043] A heating ring 33 is sleeved on the outer surface of the transition cylinder 3. A heating sleeve 211 is sleeved on the outer surface of the barrel 21. One end of the transition cylinder 3 is flange-connected to the outer end flange of the barrel 21 through a flange. The other end of the transition cylinder 3 is flange-connected to the outer surface flange of the heat insulation plate 13 through a flange.

[0044] A rotating ring 34 is rotatably connected to the inner wall surface of the transition cylinder 3. A fixed column 341 is fixedly connected to the outer surface of the rotating ring 34. The side of the fixed column 341 away from the rotating ring 34 is designed with a curved surface. When the mixing member 31 stirs inside the transition cylinder 3, the fixed column 341 will not collide with the guiding head 24.

[0045] The diameter of the screw rod 22 adopts a gradual change design, and the largest diameter end of the screw rod 22 is on the side close to the guiding head 24.

[0046] The process of mixing plastic particles:

[0047] A hopper is fixedly connected above the circumferential outer surface of the barrel 21. The recycled plastic particles are added into the interior of the barrel 21 from the hopper. The driving seat is started, and the driving seat drives the screw rod 22 to rotate clockwise in the barrel 21. The plastic particles are moved towards the moving mold 12 side through the spiral blades on the circumferential outer surface of the screw rod 22. The diameter of the screw rod 22 adopts a gradually thickening design. The diameter of the end of the screw rod 22 close to the driving seat is smaller, and the cavity formed between the circumferential outer surface of the screw rod 22 and the inner wall surface of the barrel 21 is larger, so as to facilitate the smooth falling of the plastic particles and avoid the jamming phenomenon during feeding; the diameter of the end of the screw rod 22 close to the guiding head 24 is larger, and the cavity formed between the circumferential outer surface of the screw rod 22 and the inner wall surface of the barrel 21 at this place is smaller, which can move the plastic particles towards the circumferential inner wall of the barrel 21 during the conveying process, making the plastic particles closer to the heating sleeve 211 sleeved on the outer surface, and the temperature here is higher, accelerating the melting of the plastic particles.

[0048] The plastic particles gradually becoming a liquid state move towards the transition cylinder 3 under the action of the screw rod 22. Under the pushing action of the material, at this time, the end of the check ring 26 close to the fixed mold 11 fits with the outer surface of the guiding head 24. There is a certain gap between the check ring 26 and the washer 25. The check ring 26 and the folding ring plate 261 adopt an integral structure design. The side of the folding ring plate 261 close to the fixed mold 11 enters the inside of the clamping groove 3111, and the inner wall surface of the clamping groove 3111 is completely attached to the outer surface of the folding ring plate 261. The material passes through the cavity formed by the outer surface of the washer 25 and the circumferential inner wall of the barrel 21 and continues to move forward (towards the fixed mold 11 and the moving mold 12). The material passes through the gap between the check ring 26 and the threaded rod 23 and flows into the inside of the transition cylinder 3 from the through groove opened inside the guiding head 24. Four through grooves are opened inside the guiding head 24, and four limiting grooves 323 are opened on the circumferential outer surface of the guiding head 24. The limiting grooves 323 and the through grooves are staggered, and the included angle between the limiting grooves 323 and the through grooves is 45 degrees.

[0049] Four cushion beads 231 are fixedly connected to the outer surface of the threaded rod 23. Under the action of the cushion 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 cushion bead 231 and the circumferential inner wall of the check ring 26 is small. Without hindering the inflow of plastic, it can ensure that the check ring 26 can smoothly slide on the outer surface of the threaded rod 23 in different states.

[0050] While loading the material, the guiding head 24 also synchronously drives the mixing member 31 to stir inside the transition cylinder 3. The guiding head 24 is embedded in the circumferential inner surface of the limiting ring plate 321. Among them, the side of the guiding head 24 close to the fixed mold 11 is in close contact with the limiting ring plate 321, the side of the guiding head 24 far from the fixed mold 11 is in contact with the inner surface of the limiting plate 322, and the guiding head 24 is located between the limiting ring plate 321 and the limiting plate 322. 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 is tighter), then the outer surface of the limiting block 324 in the advancing direction of clockwise rotation is in contact with the outer surface of the limiting plate 322 (the outer surface of the limiting block 324 is designed with an arc surface that fits the outer surface of the limiting plate 322). The limiting plate 322 and the limiting ring plate 321 adopt an integral structure. Through the transmission of the limiting plate 322 and the limiting block 324, the connecting ring plate 311 rotates clockwise synchronously. A stirring column 312 penetrates through the inside of the connecting ring plate 311, 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 cylinder 3 to stir the material inside the transition cylinder 3, and further plasticize it under the action of the heating ring 33 on the outer surface of the transition cylinder 3.

[0051] The transition cylinder 3 includes a straight cylinder part and a nozzle part. The nozzle part extends to the gate of the fixed mold 11, and the two are internally connected. A rotating ring 34 is rotatably connected to the inner wall of the nozzle part. The rotatable range of the rotating ring 34 inside the transition cylinder 3 is about ninety degrees. When the fixed column 341 fixed on the outer surface of the rotating ring 34 rotates synchronously under the action of the material stirring.

[0052] The rotation of the mixing member 31 inside the transition cylinder 3 will cause the plastic in a plasticized state inside to form a circulating flow, generating a specific flow state inside the transition cylinder 3. The flowing plastic is pushed outward and clockwise from near the stirring column 312, then flows downward or upward along the inner wall of the transition cylinder 3, and then returns to near the stirring column 312 from the bottom or top of the transition cylinder 3, forming a circulating flow. During this process, the flow of the material will generate a flexible thrust on the rotating ring 34 and the fixed column 341, pushing them to rotate clockwise together with the liquid material until the whole rotating ring 34 cannot move further due to being in its maximum rotation range, and the rotating ring 34 and the fixed column 341 no longer rotate and are in a relatively static state with the transition cylinder 3.

[0053] At this time, the fixed column 341 remains stationary, while the stirring column 312 continues to rotate along with the screw 22, which will cause the plasticized liquid in the transition barrel 3 to form a complex flow field. The rotation of the stirring column 312 drives the surrounding plastic to move, forming a mainstream area, while a relatively static or slow flow area will be formed around the fixed column 341. The speed difference and shear force are formed between the mainstream area and these areas, so that the plasticized liquid flows between different speed areas, increasing the mixing opportunities between the plasticized liquids. This complex flow field can avoid the simple overall flow of particles, allowing particles at different positions to fully participate in the mixing and improve the mixing uniformity. The clockwise rotation of the stirring column 312 will produce a shearing effect on the plasticized liquid, causing the plasticized liquid to be broken up, and different plastics to rub and collide with each other. At the same time, a boundary layer is formed near the surface of the stationary fixed column 341. When the plastic passes through the boundary layer, the shear force is further increased. This shearing effect helps to break the agglomeration of the plastic, so that recycled plastics of different types and properties can contact and mix with each other more fully, thereby improving the mixing quality and making the performance of the final product more stable. In this process, even if there are plastic particles that are not completely melted inside, the stirring action of the mixing element 31 can fully mix them and complete the plasticization.

[0054] Injection molding process:

[0055] After the materials inside the transition barrel 3 are mixed, the screw 22 stops rotating, the driving seat drives the screw 22 to move toward the fixed mold 11, the guide head 24 and the threaded rod 23 move synchronously, and the connecting plate 313 on the outer surface of the circumference of the guide head 24 forms a whole with the guide head 24 through the limit ring plate 321, and the connecting plate 313 also moves toward the fixed mold 11. In this process, since the screw 22 stops rotating for a short time, but the plasticized liquid inside still has a certain inertia, after colliding with the stopped screw 22, a certain reverse force is generated, and the plasticized liquid drives the rotating ring 34 to generate a small counterclockwise rotation force. When the guide head 24 moves forward, the outer end of the arc surface of the fixed column 341 touches the guide head 24 between the two adjacent through grooves and stops, and stays inside the through groove of the guide head 24 (the through groove forms a relatively concave area on the outer surface of the guide head 24). As the guide head 24 continues to move, the fixed column 341 passes through the guide head 24 in the direction of the through groove and enters the inside of the check ring 26. The threaded rod 23 and the guide head 24 adopt an integrated structural design. There are four cushion beads 231 and four through grooves. The cushion beads 231 and the through grooves are staggered, which prevents the fixing column 341 from entering the check ring 26 and colliding with the cushion beads 231.

[0056] When the screw rod 22 advances, the pressure inside the transition cylinder 3 is relatively high, which will cause the check ring 26 to slide away from the fixed mold 11 on the outer surface of the circumference of the threaded rod 23. At this time, the outer surface of the folding ring plate 261 close to the fixed mold 11 is separated from the inner wall surface of the card slot 3111, but part of the folding ring plate 261 is still inside the card slot 3111. One end of the check ring 26 away from the fixed mold 11 adopts a conical surface design that fits the outer surface of the washer 25. At this time, under the action of the pressure inside the transition cylinder 3, the conical surface of the check ring 26 is completely and tightly fitted with the conical surface of the washer 25, preventing the plasticized liquid from flowing back into the inside of the barrel 21.

[0057] During this process, the plasticized liquid originally inside the transition cylinder 3 is injected into the gate at the outer end of the fixed mold 11 along the nozzle, and then enters the cavity between the fixed mold 11 and the moving mold 12. The coolant inside the mold accelerates the cooling of the plasticized liquid. After cooling and forming, the fixed mold 11 moves away from the fixed mold 11 side under the action of an external demolding device, and the formed product is ejected through the internal ejection device to complete the blanking action. When the forming part 1 discharges materials, the screw rod 22 retracts backward, and the guiding head 24 retracts synchronously. The connecting ring plate 311 is attached to the outer surfaces of the limiting plate 322 and the limiting block 324, and retracts back to the initial position synchronously under the action of the guiding head 24. Repeat the feeding steps to transport the plasticized plastic particles into the inside of the transition cylinder 3, so that different types of plastics are fully fused, avoiding situations such as stratification, uneven color, and incomplete plasticization.

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

[0059] When regular cleaning or maintenance is required, drive the screw rod 22 to rotate reversely by a certain angle and then stop, and remove the heating ring 33. When the screw rod 22 rotates reversely, the guiding head 24 rotates reversely with it until the outer surface of the limiting block 324 rotating counterclockwise fits the arc surface of another limiting plate 322. At this time, the limiting groove 323 on the outer surface of the guiding head 24 coincides with the position of the limiting plate 322 on the outer surface of the connecting ring plate 311, and the area occupied by the limiting groove 323 is larger than the area of the limiting plate 322. Find the bolts connecting the outer flanges of the transition cylinder 3 and 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 the diagonal order. First loosen each bolt by a few turns, and then gradually screw them all off completely, which can avoid flange deformation or damage caused by uneven stress.

[0060] After all the bolts are removed, gently pry the flange at the outer ends of the transition cylinder 3 and the barrel 21 to gradually separate them in the axial direction. After separation, the inside of the transition cylinder 3 contains the mixing member 31, the rotating ring 34 and the fixing column 341, while the inside of the barrel 21 contains the guiding head 24, the washer 25, the threaded rod 23, the check ring 26 and the screw 22. The transition cylinder 3 and the barrel 21 are completely separated, and the residual plastic inside can be cleaned or maintained. Similarly, one end of the barrel 21 close to the fixed mold 11 is also connected to the heat insulation plate 13 through a flange.

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

[0062] Advantage 1: When the screw 22 rotates, it drives the mixing member 31 to rotate inside the transition cylinder 3 through the connecting member 32. After the plastic particles are preliminarily stirred during transportation, they enter the inside of the transition cylinder 3. Through the continuous rotation and stirring of the stirring column 312 inside the transition cylinder 3, plastic particles with large differences in material, shape, and additives can be effectively mixed, avoiding the phenomena of "stratification", "mottling", or "cold spots" in plastic particles with different densities and melting points, further preventing uneven composition inside the recycled plastic products, avoiding the situation of insufficient strength of the injection molded products, and thus improving the overall quality of the injection molded products. At the same time, the production efficiency and the product qualification rate will also be greatly improved.

[0063] Advantage 2: The sources, aging degrees, and pollution degrees of waste plastic particles are different, and their properties (such as molecular weight, strength, melting point) are different. After being fully mixed by the mixing member 31, the properties of new plastics and waste plastics are averaged through physical mixing, and the performance fluctuations of waste plastics are dispersed throughout the system, avoiding product defects caused by too poor local performance, thus allowing a higher proportion of waste materials to be used, reducing the use of new plastic particles, and improving the recycling rate of waste plastic particles. At the same time, after sufficient stirring, the fluidity of the whole material tends to be uniform, and the plastic fills more smoothly in the fixed mold 11 and the moving mold 12 during injection molding, reducing the resistance during the injection molding process and reducing problems such as material shortage and short shot caused by poor local fluidity.

[0064] Advantage 3: Waste plastics will adsorb moisture (such as not being completely dried after washing), residual detergents, oil stains or other pollutants during the recycling process. At high temperatures, the evaporation of moisture or the decomposition of impurities will release gases. The transition cylinder 3 can provide a temporary residence space for the plastic particles after plasticization. While the mixing member 31 is stirring, it can help the gases in the plasticized recycled waste plastics to be discharged, reducing the doping of bubbles in the plasticized liquid, avoiding problems such as surface pores, internal cavities, and silver streaks in the products caused by gas residues, improving the finished product qualification rate, reducing the injection pressure fluctuations caused by gas accumulation, and ensuring the filling stability.

[0065] Advantage 4: The diameter of the screw 22 is designed to be gradually thickened. Gradient heating accelerates melting. The diameter is small at the end close to the drive seat, and the cavity formed with the inner wall of the barrel 21 is large, facilitating the smooth falling of plastic particles, effectively avoiding jamming during feeding, ensuring smooth feeding, and improving work efficiency. The diameter of the screw 22 is large at the end close to the guide head 24, and the cavity formed with the inner wall of the barrel 21 is small, which can move the plastic particles towards the circumferential inner wall of the barrel 21, making them closer to the heating sleeve 211, accelerating the melting of plastic particles at a higher temperature, shortening the plasticization time, and improving production efficiency.

[0066] Advantage 5: The fixed column 341 remains stationary, and the stirring column 312 rotates continuously. Their relative movement forms a complex flow field of the plasticized liquid in the transition cylinder 3. The velocity difference and shear force are formed between the mainstream area and the area around the fixed column 341 where the flow velocity is relatively static or slow, increasing the mixing opportunity of the plasticized liquid, avoiding simple overall flow of particles, and improving mixing uniformity. The clockwise rotation of the stirring column 312 generates a shear effect on the plasticized liquid, breaking up the liquid and causing different plastics to rub and collide with each other. At the same time, the boundary layer near the surface of the fixed column 341 further increases the shear force, which helps to break plastic agglomeration, enabling different types and properties of recycled plastics to come into full contact and mixing, improving the mixing quality, and ensuring the 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 cylinder 3 allows operators to quickly disassemble the internal components, thoroughly remove the remaining plastic melt, avoid cross-contamination of raw materials in different batches, and reduce product defects caused by impurities. The detachable structure of the transition cylinder 3 provides a more open operating area. Operators can complete maintenance without contacting high-temperature and high-pressure components, reducing the risks of scalding and mechanical injury. The disassembly angle is more ergonomic, reducing the labor intensity of operators and improving operating comfort. When injecting new materials, the transition cylinder 3 can be removed, and the heat insulation plate 13 is connected to the outer end of the barrel 21 through a flange. When using the transition cylinder 3 for remanufacturing recycled plastic particles, the mixing part 31 is used to fully mix the recycled plastic particles evenly.

[0068] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the protection scope of the technical solutions of the 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 board (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 inside of the driving seat being arranged inside the barrel (21), 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 an outer end of the barrel (21), and a mixing element (31) for mixing external plastic being provided inside the transition tube (3); The mixing element (31) comprises a connecting ring plate (311), the connecting ring plate (311) being connected to the circumferential outer surface of the guide head (24) via a connecting piece (32) arranged inside the connecting ring plate (311), a stirring column (312) being slidably connected inside the connecting ring plate (311), and a connecting plate (313) abutting against the inner wall of the transition cylinder (3) being fixedly connected to one end of the stirring column (312) away from the connecting ring plate (311).

2. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 1, characterized in that: The connecting member (32) comprises a limiting ring plate (321), wherein the limiting ring plate (321) is fixedly connected to a side of the connecting ring plate (311) close to the stirring column (312), and a side of the connecting ring plate (311) away from the stirring column (312) is fixedly connected to a limiting plate (322), wherein four limiting plates (322) are arranged in a circular array with the screw rod (22) as the center, and a limiting groove (323) is provided on the circumferential outer surface of the guide head (24), and a limiting block (324) that fits the outer surface of the limiting plate (322) is fixedly connected to a side of the guide head (24) away from the stirring column (312).

3. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 2, characterized in that: The outer circumferential surface of the threaded rod (23) is sleeved with a washer (25) that fits 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).

4. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 3, characterized in that: A cushion bead (231) that fits the circumferential inner wall of the check ring (26) is fixedly connected to the circumferential outer surface of the threaded rod (23), 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).

5. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 4, characterized in that: A folding ring plate (261) is fixedly connected to the circumferential outer surface of the check ring (26); a 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 formed on a side of the connecting ring plate (311) away from the stirring column (312); an inner wall surface of the groove (3111) is in contact and slides with the outer surface of the folding ring plate (261).

6. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 5, 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.

7. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 6, characterized in that: A rotating ring (34) is rotatably connected to the inner wall surface of the transition cylinder (3), a fixing column (341) is fixedly connected to the outer surface of the rotating ring (34), and a side of the fixing column (341) away from the rotating ring (34) is designed with an arc surface.

8. The injection mold based on the uniform plasticization structure of recycled plastic particles according to claim 1, characterized in that: The diameter of the screw rod (22) is designed to be gradually changed, and the end of the screw rod (22) with the largest diameter is close to the side of the guide head (24).

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