Energy-saving screw
By designing single-thread, double-thread, and annular groove structures on the screw, the problems of insufficient conveying capacity and poor melting in conventional screws during plastic processing are solved, achieving full mixing and melting of materials and improving the quality of plastic products.
Patent Information
- Application Number
- CN202520321671.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-02-27
AI Technical Summary
Conventional screws have problems such as low solid conveying capacity, poor plasticization after increasing speed, and increased overheating and fluctuation of molten material during plastic processing, which affect the quality of extruded products.
An energy-saving screw is designed, including a feeding section, a melting section, a mixing section and an extrusion section. The melting section has single and double screw ribs arranged at intervals. The surface of the mixing section is provided with a feed trough and a discharge trough. The extrusion section is provided with an extrusion trough. An annular groove is set between the mixing section and the extrusion section. The material flows alternately in these structures to promote thorough mixing.
By increasing the compression ratio and mixing effect during material conveying, the melting efficiency and mixing uniformity of the material are improved, thereby enhancing the quality of plastic products.
Smart Images
Figure CN223918632U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to an energy-saving screw. Background Technology
[0002] Plastic product processing is accomplished through plastic extruders. A plastic extruder consists of a feeding system, a heating system, and a screw. It heats fixed plastic granules to a molten state and then extrudes them into corresponding molds, where they are cooled to obtain the desired plastic products. The screw is one of the core components of the extruder; its function is to convey, compact, melt, mix, and pressurize the plastic. During the screw's rotation within the barrel, friction and mutual movement occur between the plastic and the barrel wall, the bottom surface of the screw groove, the screw's advancing surface, and between the plastic particles themselves. The forward propulsion of the plastic is the result of this combination of movements, and the heat generated by friction is absorbed to raise the plastic's temperature and melt it. Conventional screws, during use, exhibit drawbacks such as low solid conveying capacity, poor plasticization at increased speed, overheating of the melt, and increased fluctuations in the molten material. These drawbacks severely affect the quality of the extruded products. Utility Model Content
[0003] To address the shortcomings mentioned above, this utility model provides an energy-saving screw.
[0004] To achieve the above objectives, this utility model provides an energy-saving screw, comprising a feeding section, a melting section, a mixing section, and an extrusion section connected in sequence. The melting section has single and double helical ridges arranged at intervals. The mixing section is a cylindrical section. Feed grooves and discharge grooves are machined at intervals on the outer circumference of the mixing section. The feed grooves and discharge grooves are distributed in a spiral shape. An annular groove is formed at the connection between the mixing section and the extrusion section. The extrusion section is a cylindrical section with a diameter matching that of the mixing section. Extrusion grooves are uniformly machined on the outer circumference of the extrusion section. The extrusion grooves are distributed in a spiral shape and open at both ends.
[0005] As a further improvement of this utility model, the double spiral ridge includes a first spiral ridge and a second spiral ridge. The end of the first spiral ridge is connected to the single spiral ridge to form an integral structure. The pitch between the second spiral ridge and the first spiral ridge gradually decreases from the feeding section to the mixing section.
[0006] As a further improvement of this utility model, the annular groove is connected to the discharge groove and the extrusion groove respectively.
[0007] As a further improvement of this utility model, the feed trough is open at one end toward the melting section and closed at the other end, the discharge trough is open at one end toward the extrusion section and closed at the other end, the depth of the feed trough gradually decreases from the open end to the closed end, and the depth of the discharge trough gradually increases from the closed end to the open end.
[0008] As a further improvement of this utility model, the depth of the extrusion groove gradually decreases from the feed end to the discharge end.
[0009] The beneficial effects of this utility model are as follows:
[0010] 1. The screw structure is provided with single and double screw ribs at intervals on the melting section. The double screw rib is formed by the first screw rib and the second screw rib. The first screw rib is connected to the single screw rib to form a whole. The pitch between the first screw rib and the second screw rib gradually decreases along the conveying direction, so that the material flows back and forth between the single screw rib and the double screw rib. At the same time, the compression ratio during material conveying is increased, which promotes the full mixing of the material.
[0011] 2. Feed troughs and discharge troughs are machined at intervals on the surface of the mixing section. The molten material is squeezed from the feed trough to the discharge trough through the gap between the mixing section and the barrel, and then enters the extrusion section, while the unmelted material flows back to the melting section to continue melting.
[0012] 3. An annular trough is set between the mixing section and the extrusion section. The material flows along the discharge trough on the mixing section into the annular trough, accumulates and mixes, and then is dispersed and extruded along the extrusion trough, so that the material is mixed more thoroughly and the plasticizing effect is better. Attached Figure Description
[0013] Figure 1 This is an overall structural diagram of an energy-saving screw according to the present invention;
[0014] Figure 2 for Figure 1 Enlarged view of point A in the middle;
[0015] Figure 3 for Figure 1 Enlarged view of point B in the middle.
[0016] In the diagram: 1. Feeding section; 2. Melting section; 21. Single spiral ridge; 22. Double spiral ridge; 221. First spiral ridge; 222. Second spiral ridge; 3. Mixing section; 31. Feed trough; 32. Discharge trough; 4. Annular trough; 5. Extrusion section; 51. Extrusion trough. Detailed Implementation
[0017] like Figure 1 As shown, the energy-saving screw of this utility model includes a feeding section 1, a melting section 2, a mixing section 3, and an extrusion section 5 connected in sequence. Single screw ribs 21 and double screw ribs 22 are arranged at intervals on the melting section 2 (see...). Figure 3The double-screw 22 includes a first screw 221 and a second screw 222. The end of the first screw 221 is connected to the single screw 21 to form an integral structure. The pitch between the second screw 222 and the first screw 221 gradually decreases from the feeding section 1 to the mixing section 3. The mixing section 3 is a cylindrical section. Feed grooves 31 and discharge grooves 32 are machined at intervals on the outer circumference of the mixing section 3. The feed grooves 31 and discharge grooves 32 are spirally distributed. The feed groove 31 is open at one end facing the melting section 2 and closed at the other end. The discharge groove 32 is open at one end facing the extrusion section 5 and closed at the other end. The depth of the feed groove 31 gradually decreases from the open end to the closed end, and the depth of the discharge groove 32 gradually increases from the closed end to the open end. An annular groove 4 is formed at the connection between the mixing section 3 and the extrusion section 5. The extrusion section 5 is a cylindrical section with a diameter matching that of the mixing section 3. Extrusion grooves 51 are uniformly machined on the outer circumference of the extrusion section 5. The extrusion grooves 51 are spirally distributed and open at both ends (see...). Figure 2 The depth of the extrusion groove 51 gradually decreases from the feed end to the discharge end, and the annular groove 4 is connected to the discharge groove 32 and the extrusion groove 51 respectively.
[0018] This screw structure features single and double screw ribs spaced apart on the melting section. The double screw ribs are formed by a first and a second screw rib, with the first rib connected to the single screw rib to form a single unit. The pitch between the first and second screw ribs gradually decreases along the conveying direction, allowing the material to flow back and forth between the single and double screw ribs. This increases the compression ratio during material conveying and promotes thorough mixing. The mixing section has spaced feed troughs and discharge troughs machined on its surface. Molten material is squeezed from the feed trough to the discharge trough through the gap between the mixing section and the barrel, then enters the extrusion section. Unmelted material flows back to the melting section to continue melting. An annular groove is installed between the mixing and extrusion sections. Material flows along the discharge trough on the mixing section into the annular groove, accumulates and mixes, and then is dispersed and extruded along the extrusion groove, resulting in more thorough mixing and better plasticizing.
[0019] In practical use, for ease of understanding of this utility model, it will be described in conjunction with the accompanying drawings;
[0020] The mixed material enters the feeding section of the screw through the extruder's feed inlet. In the feeding section, the material remains solid. Through screw rotation and shearing, and friction between the materials, it is compressed and heated simultaneously before being conveyed to the screw's melting section. After entering the melting section, the material continues to be heated, and further subjected to friction between the materials and shearing between the material and the screw, gradually compacting and softening it into a mixture of melt and solid. This mixture is slowly conveyed to the mixing section. The closer to the mixing section, the higher the melt content and the lower the solid content. The melting section is designed with spaced single and double screw ridges, with the pitch between the first and second screw ridges in the double screw ridges extending along the feed path. The material direction continuously decreases and changes state, and the material flows alternately between single-screw and double-screw, forming a turbulent state. At the same time, it increases the compression ratio during material conveying and accelerates the melting and mixing of the material. After the material enters the mixing section, the mixing section separates the melt in the material from the remaining unmelted solids. The molten material is squeezed from the feed chute to the discharge chute through the gap between the mixing section and the barrel, and then enters the annular trough, while the unmelted material flows back to the melting section to continue melting. The molten material enters the annular trough for further accumulation and mixing, and then flows dispersed along the extrusion groove on the extrusion section. Finally, it is uniformly extruded through the flow channel formed by the screw head and the barrel.
[0021] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. An energy-saving screw, characterized in that: The system includes a feeding section (1), a melting section (2), a mixing section (3), and an extrusion section (5) connected in sequence. The melting section (2) has single spiral ridges (21) and double spiral ridges (22) arranged at intervals. The mixing section (3) is a cylindrical section. The outer circumference of the mixing section (3) is machined with a feed groove (31) and a discharge groove (32) at intervals. The feed groove (31) and the discharge groove (32) are spirally distributed. The connection between the mixing section (3) and the extrusion section (5) forms an annular groove (4). The extrusion section (5) is a cylindrical section with a diameter matching that of the mixing section (3). The outer circumference of the extrusion section (5) is uniformly machined with extrusion grooves (51). The extrusion grooves (51) are spirally distributed and open at both ends.
2. The energy-saving screw according to claim 1, characterized in that: The double-screw edge (22) includes a first screw edge (221) and a second screw edge (222). The end of the first screw edge (221) is connected to the single screw edge (21) to form an integral structure. The pitch between the second screw edge (222) and the first screw edge (221) gradually decreases from the feeding section (1) to the mixing section (3).
3. The energy-saving screw according to claim 1, characterized in that: The annular groove (4) is connected to the discharge groove (32) and the extrusion groove (51) respectively.
4. The energy-saving screw according to claim 1, characterized in that: The feed trough (31) is open at one end toward the melting section (2) and closed at the other end. The discharge trough (32) is open at one end toward the extrusion section (5) and closed at the other end. The depth of the feed trough (31) gradually decreases from the open end to the closed end, and the depth of the discharge trough (32) gradually increases from the closed end to the open end.
5. An energy-saving screw according to claim 1, characterized in that: The depth of the extrusion groove (51) gradually decreases from the feed end to the discharge end.