High-mixing and efficient injection molding screw and injection molding machine
By designing high-mixed and efficient injection molding screws and adopting a combined structure of transition sections and separation sections, the problem of difficult injection molding screws in the prior art to take into account high melting quality, good color mixing effect and rapid plasticization efficiency, achieving high-efficiency plasticization and Low energy consumption effect.
Patent Information
- Application Number
- CN202421269368.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-04
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-06-04
AI Technical Summary
It is difficult for existing injection molded screws to take into account high melting quality, good color mixing effect and rapid plasticization efficiency, and insufficient screw strength can easily lead to torsional fracture.
A high-mixed and efficient injection molding screw is designed, adopting a combined structure of transition section, cut section, separation section and mixing section. Through the gradient base diameter of the transition section and the double-thread structure of the separation section, the fatigue resistance of the screw is improved. and plasticization efficiency.
It achieves efficient plasticization, improves melting and color mixing effects, reduces the risk of screw fracture, improves reliability, and reduces plasticization energy consumption.
Smart Images
Figure CN222473276U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of injection molding machines, in particular to a high-mix and high-efficiency injection molding screw and an injection molding machine. Background Art
[0002] Nowadays, injection molding production is increasingly pursuing high quality, high output and low cost of products, especially PET products (including various preforms or finished products), PP products (various disposable tableware, medical packaging consumables and turnover boxes, etc.), PE products (various chemical barrels and bottle caps, etc.) and PS products (aircraft cups, plastic bowls), etc., which have huge demand. Plastic raw materials are plasticized by the screw of the injection molding machine. The plasticizing performance of the screw has a great influence on the production efficiency and quality of the product. The plasticizing time of the screw often accounts for about 50% of the product production cycle, and the plasticizing quality of the screw determines the appearance and performance of the product.
[0003] In the prior art, the screw usually adopts a three-stage single-thread or twin-screw structure, coupled with a mixing ring or a barrier ring. It is difficult to take into account high melting quality, good color mixing effect and fast plasticizing efficiency at the same time in design, and it is difficult to ensure the strength of the screw itself under the premise of efficient plasticizing without torsional fracture and other phenomena.
[0004] Therefore, it is necessary to solve the above technical problems. Summary of the invention
[0005] In view of the above technical problems, the utility model provides a high-mixing and high-efficiency injection molding screw and an injection molding machine, which simultaneously improve the plasticizing melting, color mixing effect and plasticizing efficiency, reduce the risk of injection molding screw breakage, improve the reliability of the injection molding screw, and reduce plasticizing energy consumption, so as to meet the high-quality, high-efficiency and low-cost production of various types of bottles, boxes, cups and barrels, frames, boxes, covers and other packaging and medical injection molding products.
[0006] To achieve the above purpose, the technical solution of the utility model is:
[0007] A high-mixing and high-efficiency injection screw comprises an installation section, a feeding section, a separation section and a mixing section which are sequentially arranged along a conveying direction; the feeding section comprises a transition section and a conveying section, the feeding section is a single-thread structure, and the pitch of the feeding section remains unchanged; the bottom diameter of the transition section changes gradually from large to small, and the bottom diameter of the conveying section remains unchanged.
[0008] The transition section of the high-mix and high-efficiency injection screw changes gradually from large to small along the conveying direction, avoiding the sudden change of the shaft diameter at the intersection of the installation section and the unloading section, which causes a large stress concentration, greatly reducing the risk of twisting off here, and improving the fatigue resistance and screw reliability. At the same time, due to the existence of the transition section, the depth of the unloading trough can be appropriately deepened, increasing the conveying capacity of the raw materials in the unloading section.
[0009] According to a further optimization scheme, the ratio of the maximum value to the minimum value of the bottom diameter of the transition section is 1.1 to 1.2. This ratio is the optimal ratio range for the gradual change of the bottom diameter of the transition section. It is easy to manufacture and better avoids greater stress concentration.
[0010] In a further optimized solution, the separation section includes a parallel separation section and a compression section, the separation section is a double thread structure of a main thread and a secondary thread, and the main thread is connected to the thread of the blanking section;
[0011] The pitch of the main thread of the separation section remains unchanged, and its value is greater than the pitch of the feeding section; the pitch of the secondary thread is equal to the pitch of the main thread in the parallel separation section, and the pitch of the secondary thread is not equal to the pitch of the main thread in the compression section; the main thread and the secondary thread remain parallel in the parallel separation section.
[0012] The pitch of the main thread of the separation section of the high-mix and high-efficiency injection screw is greater than the pitch of the feeding section, which helps to improve the raw material passing capacity of the separation section, reduce the blocking phenomenon in the raw material conveying process, and reduce the flow resistance. Therefore, the final output of the raw material is increased, and the plasticizing capacity and efficiency are greatly improved.
[0013] According to a further optimization scheme, the main thread pitch of the separation section is 1.1 to 1.3 times the pitch of the feeding section. This value is the optimal range of the main thread pitch of the separation section and the feeding section pitch, which is easy to manufacture and effectively improves the passing efficiency of the raw materials in the separation section.
[0014] In a further optimized solution, the main thread ridge width is greater than the secondary thread ridge width, the main thread ridge width is 0.1 times the injection screw diameter, and the secondary thread ridge width can be 3 to 5 mm. This solution discloses the optimal value range of the main thread ridge width and the secondary thread ridge width of the separation section.
[0015] A further optimization scheme is that the bottom diameter of the main thread of the separation section is connected to the end of the bottom diameter of the conveying section, and the value of the bottom diameter of the main thread of the separation section gradually increases along the conveying direction; the value of the bottom diameter of the auxiliary thread of the parallel separation section gradually decreases along the conveying direction; the value of the bottom diameter of the auxiliary thread of the compression section gradually increases along the conveying direction; the bottom diameter of the auxiliary thread of the parallel separation section is connected to the end of the bottom diameter of the auxiliary thread of the compression section.
[0016] In a further optimized solution, the radius of the main thread of the separation section is greater than the radius of the secondary thread, and the radius difference is 0.4-1.5 mm. The larger the diameter of the injection screw, the greater the radius difference between the two. This solution discloses the optimal radius range of the main thread and the secondary thread of the separation section.
[0017] Further optimization scheme, the parallel separation section secondary thread divides the main thread groove into two parts, the width ratio of the two parts is 1.9 to 2.1. The parallel separation section divides the main thread groove into two parts, which can effectively separate solid plastic and liquid plastic, and store them in the grooves on both sides respectively, forming two wider channels to avoid mixing the two and affecting transportation and compression; at the same time, since the solid plastic groove width is large and remains unchanged, there is sufficient heat absorption area, and the gradual increase in the bottom diameter has a compression effect on the solid raw material.
[0018] In a further optimized solution, the mixing section is a barrier ring structure or a pin structure or a combination of the two. The mixing section can further fuse the liquid material. For example, if masterbatch, color powder or color oil is added to the solid plastic before unloading, the colors can be fully mixed and evenly mixed through this section, further enhancing the melting effect and color mixing effect, and the overall melting effect and color mixing effect are greatly improved.
[0019] According to a further optimized solution, the ratio of the sum of the lengths of the feeding section, the separation section and the mixing section to the diameter of the injection molding screw is 20 to 26. The solution discloses the optimal screw length-to-diameter ratio of the injection molding screw.
[0020] According to a further optimization scheme, the ratio of the sum of the lengths of the feeding section, the separation section and the mixing section to the diameter of the injection screw is 22 to 25.
[0021] An injection molding machine comprises a barrel, a heating ring and a shooting platform hopper, and also comprises any one of the above-mentioned high-mix and high-efficiency injection molding screws.
[0022] Compared with the prior art, the utility model has the following technical advantages:
[0023] 1. The bottom diameter of the transition section of the high-mix and high-efficiency injection molding screw changes gradually from small to large from left to right, avoiding the sudden change of the shaft diameter at the intersection of the installation section and the feeding section, which causes a large stress concentration, greatly reducing the risk of being twisted off here, and improving the fatigue resistance and screw reliability. At the same time, due to the existence of the transition section, the depth of the feeding trough can be appropriately deepened, increasing the conveying capacity of the raw materials in the feeding section; and because the pitch of the main thread of the separation section is greater than the pitch of the thread of the feeding section, it helps to improve the passing capacity of the raw materials in the separation section, reduce the jamming phenomenon in the raw material conveying process, and reduce the circulation resistance. Therefore, the final output of the raw materials is increased, and the plasticizing capacity and efficiency are greatly improved;
[0024] 2. The parallel separation section of the high-mixing and high-efficiency injection screw divides the main screw groove into two parts, which can effectively separate solid plastic and liquid plastic, and store them in the screw grooves on both sides respectively, forming two wider channels to avoid the two mixing together and affecting transportation and compression; at the same time, since the solid plastic groove width is large and remains unchanged, there is sufficient heat absorption area, and the gradual increase in the bottom diameter has a compression effect on the solid raw material, and the mixing section further enhances the melting effect and color mixing effect, so the overall melting effect and color mixing effect are greatly improved;
[0025] 3. Due to the reasonable matching of structure and screw groove size, the high-mix and high-efficiency injection screw can transport raw materials smoothly in each channel, reduce the transportation resistance and unnecessary compression and shearing, reduce the useless work in the plasticizing process, and thus reduce the plasticizing energy consumption and the energy consumption of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 This is a structural diagram of a specific embodiment of the high-mix and high-efficiency injection screw of the utility model;
[0027] Figure 2 yes Figure 1 Assembly diagram of the injection molding screw, barrel and heating ring.
[0028] In the figure: installation section M, feeding section A, transition section A1, conveying section A2, separation section B, parallel separation section B1, compression section B2, mixing section C, injection screw diameter D, transition section bottom diameter a, conveying section bottom diameter b, separation section main thread bottom diameter c, feeding section pitch L1, main thread pitch L2, secondary thread pitch L3, main thread ridge width t1, secondary thread ridge width t2, parallel separation section secondary thread bottom diameter e, compression section secondary thread bottom diameter f. DETAILED DESCRIPTION
[0029] The present invention will be further described in detail below with reference to the embodiments in the accompanying drawings.
[0030] like Figure 1 As shown, a specific embodiment of the high-mix and high-efficiency injection molding screw of the utility model includes an installation section M, a feeding section A, a separation section B and a mixing section C arranged in sequence along the conveying direction; the feeding section A includes a transition section A1 and a conveying section A2, the feeding section A is a single-thread structure, and the pitch L1 of the feeding section remains unchanged; the bottom diameter a of the transition section changes gradually from large to small, and the bottom diameter of the conveying section A2 remains unchanged. The ratio of the maximum value to the minimum value of the bottom diameter a of the transition section is 1.1 to 1.2. This ratio is the optimal ratio range for the gradual change of the bottom diameter of the transition section, which is easy to manufacture and better avoids greater stress concentration.
[0031] like Figure 1As shown, the separation section B includes a parallel separation section B1 and a compression section B2. The separation section B is a double thread structure of a main thread and a secondary thread, and the main thread is connected to the thread of the unloading section A. The main thread pitch L2 of the separation section B remains unchanged, and its value is greater than the unloading section pitch L1; the secondary thread pitch L3 is equal to the main thread pitch L2 in the parallel separation section B1, and the secondary thread pitch L3 is not equal to the main thread pitch L2 in the compression section B2; the main thread and the secondary thread remain parallel in the parallel separation section B1.
[0032] The high-mix and high-efficiency injection screw transition section gradually changes from large to small along the conveying direction, avoiding the sudden change of the shaft diameter at the intersection of the installation section and the unloading section, which causes a large stress concentration, greatly reducing the risk of being twisted off here, and improving the fatigue resistance and screw reliability. At the same time, due to the existence of the transition section, the depth of the unloading trough can be appropriately deepened, increasing the conveying capacity of the raw materials in the unloading section. The main thread pitch of the separation section is greater than the thread pitch of the unloading section, which helps to improve the raw material passing capacity of the separation section, reduce the blocking phenomenon in the raw material conveying process, and reduce the circulation resistance. Therefore, the final output of the raw material is increased, and the plasticizing capacity and efficiency are greatly improved.
[0033] like Figure 1 As shown, the main thread pitch L2 of the separation section B is 1.1 to 1.3 times the pitch L1 of the feeding section. This value is the optimal range of the main thread pitch of the separation section and the feeding section pitch, which is easy to manufacture and effectively improves the passing efficiency of the raw materials in the separation section.
[0034] like Figure 1 As shown, the main thread ridge width t1 is greater than the secondary thread ridge width t2, the main thread ridge width t1 is 0.1 times the injection screw diameter D, and the secondary thread ridge width t2 can be 3 to 5 mm. This value range is the optimal value range of the main thread ridge width and the secondary thread ridge width of the separation section.
[0035] like Figure 1 As shown, the bottom diameter c of the main thread of the separation section is connected to the end of the bottom diameter b of the conveying section, and the value of the bottom diameter c of the main thread of the separation section gradually increases along the conveying direction; the value of the bottom diameter e of the auxiliary thread of the parallel separation section gradually decreases along the conveying direction; the value of the bottom diameter f of the auxiliary thread of the compression section gradually increases along the conveying direction; the bottom diameter e of the auxiliary thread of the parallel separation section is connected to the end of the bottom diameter f of the auxiliary thread of the compression section.
[0036] like Figure 1 As shown, the radius of the main thread of the separation section B is greater than the radius of the secondary thread, and the radius difference s is 0.4-1.5 mm. The larger the injection screw diameter D, the larger the radius difference s. This numerical range is the optimal radius range of the main thread and the secondary thread of the separation section.
[0037] like Figure 1As shown in the figure, the parallel separation section B1 secondary thread divides the main thread groove into two parts, the widths of which are La and Lb respectively, and the ratio of the widths of the two parts is 1.9 to 2.1. The parallel separation section divides the main thread groove into two parts, which can effectively separate solid plastic and liquid plastic, and store them in the grooves on both sides respectively, forming two wider channels to prevent the two from mixing and affecting transportation and compression; at the same time, since the solid plastic groove width is large and remains unchanged, there is sufficient heat absorption area, and the gradual increase in the bottom diameter has a compression effect on the solid raw material.
[0038] like Figure 1 As shown, the mixing section C is a barrier ring structure or a pin structure or a combination of the two. The mixing section C can further fuse the liquid material. For example, if masterbatch, color powder or color oil is added to the solid plastic before unloading, the colors can be fully mixed and evenly mixed through this section, further enhancing the melting effect and color mixing effect, and the overall melting effect and color mixing effect are greatly improved.
[0039] like Figure 1 As shown, the ratio of the sum of the lengths of the feeding section A, the separation section B and the mixing section C to the injection screw diameter D is 20 to 26, and the optimal ratio is 22 to 25. This ratio is the optimal screw length-to-diameter ratio of the injection screw.
[0040] The utility model also discloses an injection molding machine, such as Figure 2 As shown, the injection molding machine of this embodiment includes the above-mentioned injection screw 1, barrel 2, heating coil 3 and shooting platform hopper 9; the separation section B of the injection screw 1 has a main thread 5 and a secondary thread 6; the barrel 2 has a barrel inner wall 4, which forms a solid raw material groove 7 and a liquid raw material groove 8 with the thread groove of the injection screw 1.
[0041] like Figure 1 and Figure 2 As shown, the raw material is discharged from the hopper 9 of the shooting platform, and enters the parallel separation section B1 after being conveyed and heated in the discharge section A along the conveying direction. The heating coil 3 heats the barrel 2 and transfers the heat to the inner wall 4 of the barrel. The inner wall 4 of the barrel contacts the raw material within a certain thickness range, and the raw material becomes liquid. During the rotation of the screw, the liquid raw material can enter the liquid raw material tank 8 through the gap s between the secondary thread 6 and the inner wall 4, and the solid raw material always exists in the solid raw material tank 7 at the bottom of the liquid raw material.
[0042] like Figure 1 and Figure 2 As shown, the width La of the solid raw material groove 7 is relatively wide and remains unchanged, so that the solid raw material in the groove has a good contact length with the inner wall 4 of the barrel and can be fully heated; and because Figure 1 The bottom diameter c of the main thread of the middle separation section changes gradually from small to large, and the depth ha of the solid raw material groove 7 gradually becomes shallower. The solid raw material is sheared and compressed in the solid raw material groove 7 during the transportation process. Figure 1The bottom diameter e of the secondary thread of the parallel separation section changes gradually from large to small, the depth hb of the liquid raw material groove 8 with a fixed groove width Lb gradually deepens, and the volume of the liquid raw material groove 8 gradually increases, which can store more liquid raw materials without being subjected to shear.
[0043] like Figure 1 As shown, the injection screw has a mixing section C, which is not provided with threads and is usually any one of a barrier ring structure and a pin structure or a combination of the two. The mixing section C, as a supplement to the plasticizing effect of the separation section B, can further fuse the liquid material and fully diffuse and mix the color elements added to the solid plastic before feeding to obtain a high-quality melt.
[0044] In summary, the utility model is as described in the specification and the illustrations, and actual samples are made and tested for multiple times. From the test results, it is proved that the utility model can achieve the expected purpose and its practicality is beyond doubt. The above embodiments are only used to facilitate the description of the content of the utility model, and are not formally limited to it; any equivalent embodiment made by partial changes or modifications made by anyone with common knowledge in the technical field of the utility model without departing from the scope of the technical features and similar features of the utility model, using the technical content disclosed by the utility model, belongs to the protection scope of the utility model.
Claims
1. A high-mix and high-efficiency injection screw, characterized in that: The invention comprises an installation section (M), a material discharge section (A), a separation section (B) and a mixing section (C) which are sequentially arranged along the conveying direction; the material discharge section (A) comprises a transition section (A1) and a conveying section (A2); the material discharge section (A) is a single-thread structure, and the pitch (L1) of the material discharge section remains unchanged; the bottom diameter (a) of the transition section changes gradually from large to small, and the bottom diameter (b) of the conveying section remains unchanged.
2. The high-mix and high-efficiency injection screw according to claim 1 is characterized in that: The ratio of the maximum value to the minimum value of the bottom diameter (a) of the transition section is 1.1 to 1.
2.
3. The high-mix and high-efficiency injection screw according to claim 1 is characterized in that: The separation section (B) comprises a parallel separation section (B1) and a compression section (B2); the separation section (B) is a double thread structure of a main thread and a secondary thread, and the main thread is connected to the thread of the feeding section (A); The main thread pitch (L2) of the separation section (B) remains unchanged, and its value is greater than the pitch (L1) of the feeding section; the secondary thread pitch (L3) in the parallel separation section (B1) is equal to the main thread pitch (L2), and the secondary thread pitch (L3) in the compression section (B2) is not equal to the main thread pitch (L2); the main thread in the parallel separation section (B1) remains parallel to the secondary thread.
4. The high-mix and high-efficiency injection screw according to claim 3 is characterized in that: The main thread pitch (L2) of the separation section (B) is 1.1 to 1.3 times the main thread pitch (L1) of the feeding section.
5. The high-mix and high-efficiency injection screw according to claim 3 is characterized in that The thread ridge width (t1) is greater than the secondary thread ridge width (t2), the primary thread ridge width (t1) is 0.1 times the value of the injection screw diameter (D), and the secondary thread ridge width (t2) can be 3 to 5 mm.
6. The high-mix and high-efficiency injection screw according to claim 3 is characterized in that: The bottom diameter (c) of the main thread of the separation section is connected to the end of the bottom diameter (b) of the conveying section, and the value of the bottom diameter (c) of the main thread of the separation section gradually increases along the conveying direction; the value of the bottom diameter (e) of the auxiliary thread of the parallel separation section gradually decreases along the conveying direction; the value of the bottom diameter (f) of the auxiliary thread of the compression section gradually increases along the conveying direction; the bottom diameter (e) of the auxiliary thread of the parallel separation section is connected to the end of the bottom diameter (f) of the auxiliary thread of the compression section.
7. The high-mix and high-efficiency injection screw according to claim 3 is characterized in that: The radius of the main thread of the separation section (B) is greater than the radius of the secondary thread, and the radius difference is 0.4-1.5 mm. The larger the diameter of the injection molding screw, the greater the radius difference between the two.
8. The high-mix and high-efficiency injection screw according to claim 3 is characterized in that: The secondary thread of the parallel separation section (B1) divides the screw groove of the main thread into two left and right parts, and the width ratio of the two parts is 1.9 to 2.
1.
9. The high-mix and high-efficiency injection screw according to claim 1, characterized in that: The mixing section (C) is a barrier ring structure or a pin structure or a combination of the two.
10. The high-mix and high-efficiency injection screw according to claim 1, characterized in that: The ratio of the sum of the lengths of the feeding section (A), the separation section (B) and the mixing section (C) to the diameter of the injection screw is 20-26.
11. The high-mix and high-efficiency injection screw according to claim 10, characterized in that: The ratio of the sum of the lengths of the feeding section (A), the separation section (B) and the mixing section (C) to the diameter of the injection screw is 22-25.
12. An injection molding machine, comprising a barrel (2), a heating ring (3) and a shooting platform hopper (9), characterized in that: It also includes the high-mix and high-efficiency injection molding screw as described in any one of claims 1 to 11.