Material mixing mechanism and extruder

Abstract

The invention belongs to the technical field of extruders, and discloses a material mixing mechanism and an extruder, in the material mixing mechanism, when a first meshing element and a second meshing element rotate relative to a machine barrel, a material can be periodically segmented through a first convex tooth assembly and a second convex tooth assembly, and recombination and drawing are completed in the process; in addition, in the first convex tooth assembly, a plurality of first convex teeth are arranged at intervals in the circumferential direction of the first meshing element, and in the second convex tooth assembly, a plurality of second convex teeth are arranged at intervals in the circumferential direction of the second meshing element, so that when the high-solid-content solid particles and the non-Newtonian liquid are mixed, the high-solid-content solid particles and the non-Newtonian liquid are uniformly mixed. The high-solid-content solid particles can be extruded into the tooth grooves between the adjacent first convex teeth or the tooth grooves between the adjacent second convex teeth, and high-frequency mechanical segmentation, recombination and drawing are triggered, so that the solid particles are ensured to be uniformly dispersed in the non-Newtonian fluid, and the mixing effect is improved.

Description

Technical Field

[0001] This invention relates to the field of extruder technology, and more particularly to a material mixing mechanism and an extruder. Background Technology

[0002] Both energetic material processing and lithium battery manufacturing involve mixing high-solids-content solid particles with non-Newtonian liquids (such as adhesives and curing agents). Currently, twin-screw extruders are commonly used for material mixing. A twin-screw extruder consists of two screw elements with interlocking, staggered teeth. Their high-speed rotation generates high shear forces to achieve material mixing and transport. However, the flow and mixing of particles in high-solids-content systems within non-Newtonian fluids is extremely difficult. After feeding, solids cannot be fully mixed with the non-Newtonian fluid in this strong shear field. Therefore, this type of extruder is not suitable for mixing high-solids-content solid particles with non-Newtonian liquids. Summary of the Invention

[0003] According to one aspect of the invention, a material mixing mechanism is provided to solve the problem that existing twin-screw extruders are not suitable for mixing high-solids-content solid particles with non-Newtonian liquids.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: Material mixing mechanism, including: barrel; The first meshing element is shaft-shaped and is disposed inside the barrel and is rotatable relative to the barrel. The outer peripheral wall of the first meshing element is provided with a plurality of first tooth assemblies spaced apart along the axial direction of the first meshing element. The first tooth assembly includes a plurality of first teeth spaced apart along the circumferential direction of the first meshing element. The second meshing element is shaft-shaped and disposed inside the barrel. It is rotatable relative to the barrel, and the rotation direction of the second meshing element is the same as that of the first meshing element. The outer peripheral wall of the second meshing element is provided with a plurality of second tooth assemblies spaced apart along the axial direction of the second meshing element. The second tooth assembly includes a plurality of second teeth spaced apart along the circumferential direction of the second meshing element. The first meshing element is parallel to and spaced apart from the second meshing element. Along the axial direction of the second meshing element, the first tooth assembly and the second tooth assembly are misaligned.

[0005] As a preferred embodiment of the material mixing mechanism, in the first tooth assembly, there is a first tooth groove between two adjacent first teeth, and in the second tooth assembly, there is a second tooth groove between two adjacent second teeth. When the first meshing element and the second meshing element rotate relative to the barrel, the first tooth and the second tooth groove are positioned opposite each other along the axial direction of the first meshing element, and the second tooth and the first tooth groove are positioned opposite each other along the axial direction of the second meshing element.

[0006] As a preferred embodiment of the material mixing mechanism, along the circumferential direction of the first meshing element, the central angle corresponding to the tooth tip of the first tooth is smaller than the central angle corresponding to the tooth root of the first tooth; along the circumferential direction of the second meshing element, the central angle corresponding to the tooth tip of the second tooth is smaller than the central angle corresponding to the tooth root of the second tooth.

[0007] As a preferred embodiment of the material mixing mechanism, the first tooth assembly includes 8 to 12 first teeth, and the second tooth assembly includes 8 to 12 second teeth.

[0008] As a preferred embodiment of the material mixing mechanism, the outer diameters of the first meshing element and the second meshing element are both R1, the height of the top surface of the first tooth relative to the outer wall of the first meshing element and the height of the top surface of the second tooth relative to the outer wall of the second meshing element are both R2, and 0.3≤R2 / R1≤0.6.

[0009] As a preferred embodiment of the material mixing mechanism, there is always a gap between the top surface of the first tooth and the outer wall of the second meshing element; there is always a gap between the top surface of the second tooth and the outer wall of the first meshing element.

[0010] As a preferred embodiment of the material mixing mechanism, when the first meshing element and the second meshing element rotate relative to the barrel, the minimum gap between the top surface of the first tooth and the outer wall of the second meshing element, and the minimum gap between the top surface of the second tooth and the outer wall of the first meshing element, are both d, where d≤1mm.

[0011] As a preferred embodiment of the material mixing mechanism, a gap exists between the first tooth assembly and the second tooth assembly along the axial direction of the second meshing element.

[0012] As a preferred embodiment of the material mixing mechanism, it further includes an engagement element drive structure, the output end of which has a first spline and a second spline, the first engagement element having a first spline hole for connecting the first spline, and the second engagement element having a second spline hole for connecting the second spline.

[0013] According to another aspect of the invention, an extruder is provided, including the aforementioned material mixing mechanism, and further including a material conveying mechanism for conveying the material to be mixed into the interior of the barrel and conveying the mixed material inside the barrel out of the barrel.

[0014] The beneficial effects of this invention are: This invention provides a material mixing mechanism, including a barrel, a first meshing element, and a second meshing element. The first meshing element is shaft-shaped, disposed inside the barrel, and rotatable relative to the barrel. The outer peripheral wall of the first meshing element is provided with a plurality of first tooth assemblies spaced apart along the axial direction of the first meshing element. Each first tooth assembly includes a plurality of first teeth spaced apart along the circumferential direction of the first meshing element. The second meshing element is shaft-shaped, disposed inside the barrel, and rotatable relative to the barrel. The rotation direction of the second meshing element is the same as that of the first meshing element. The outer peripheral wall of the two meshing elements is provided with a plurality of second tooth assemblies spaced apart along the axial direction of the second meshing element. The second tooth assembly includes a plurality of second teeth spaced apart along the circumferential direction of the second meshing element. The first meshing element and the second meshing element are parallel and spaced apart. Along the axial direction of the second meshing element, the first tooth assembly and the second tooth assembly are staggered. With this arrangement, when the first meshing element and the second meshing element rotate relative to the barrel, the material can be periodically divided by the first tooth assembly and the second tooth assembly, and reorganization and drawing can be completed in the process to achieve efficient solid-liquid mixing. Furthermore, since multiple first teeth are spaced apart along the circumferential direction of the first meshing element in the first tooth assembly, and multiple second teeth are spaced apart along the circumferential direction of the second tooth assembly, when mixing high-solids-content solid particles with non-Newtonian fluids, the high-solids-content solid particles can be squeezed into the grooves between adjacent first teeth or adjacent second teeth, triggering high-frequency mechanical segmentation, recombination, and stretching, ensuring that the solid particles are uniformly dispersed in the non-Newtonian fluid, thereby improving the mixing effect.

[0015] The present invention also provides an extruder, including the above-mentioned material mixing mechanism, and further including a material conveying mechanism. The material conveying mechanism is used to convey the material to be mixed into the interior of the barrel and to convey the mixed material inside the barrel out of the barrel. In the material mixing mechanism, when the first meshing element and the second meshing element rotate relative to the barrel, the material can be periodically divided by the first tooth assembly and the second tooth assembly, and in this process, reorganization and stretching are completed to achieve efficient solid-liquid mixing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the material mixing mechanism in an embodiment of the present invention; Figure 2This is a schematic diagram of the structure of the first meshing element and the second meshing element in an embodiment of the present invention; Figure 3 This is a side view schematic diagram of the first meshing element and the second meshing element in an embodiment of the present invention; Figure 4 This is a side view schematic diagram of the first engaging element in an embodiment of the present invention; Figure 5 This is a side view schematic diagram of the second engaging element in an embodiment of the present invention; Figure 6 This is a top view schematic diagram of the first meshing element and the second meshing element in an embodiment of the present invention.

[0017] In the picture: 1. Barrel; 11. First through hole; 12. Second through hole; 2. First meshing element; 21. First tooth assembly; 211. First tooth; 212. First tooth groove; 22. First spline hole; 3. Second meshing element; 31. Second tooth assembly; 311. Second tooth; 312. Second tooth groove; 32. Second spline hole. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0019] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0020] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0021] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0022] Both energetic material processing and lithium battery manufacturing involve mixing high-solids-content solid particles with non-Newtonian liquids (such as adhesives and curing agents). Currently, twin-screw extruders are commonly used for material mixing. A twin-screw extruder consists of two screw elements with interlocking, staggered teeth. Their high-speed rotation generates high shear forces to achieve material mixing and transport. However, the flow and mixing of particles in high-solids-content systems within non-Newtonian fluids is extremely difficult. After feeding, solids cannot be fully mixed with the non-Newtonian fluid in this strong shear field. Therefore, this type of extruder is not suitable for mixing high-solids-content solid particles with non-Newtonian liquids.

[0023] To address this issue, this embodiment provides a material mixing mechanism to solve the problem that existing twin-screw extruders are not suitable for mixing high-solids-content particles with non-Newtonian liquids, and can be applied in the field of extruder technology. In this embodiment, the material mixing mechanism is specifically used for mixing high-solids-content particles with non-Newtonian liquids, while in other embodiments, the material mixing mechanism can also be used for mixing other types of materials.

[0024] Reference Figures 1-6The material mixing mechanism includes a barrel 1, a first meshing element 2, and a second meshing element 3. The first meshing element 2 is shaft-shaped and disposed inside the barrel 1, and can rotate relative to the barrel 1. The outer peripheral wall of the first meshing element 2 is provided with a plurality of first tooth assemblies 21 spaced apart along the axial direction of the first meshing element 2. Each first tooth assembly 21 includes a plurality of first teeth 211 spaced apart along the circumferential direction of the first meshing element 2. The second meshing element 3 is shaft-shaped and disposed inside the barrel 1, and can rotate relative to the barrel 1. The rotation direction of the second meshing element 3 is the same as that of the first meshing element 2, in order to reduce shearing of the material. The outer peripheral wall of the second meshing element 3 is provided with a plurality of second tooth assemblies 31 spaced apart along the axial direction of the second meshing element 3. The second tooth assembly 31 includes a plurality of second teeth 311 spaced apart along the circumferential direction of the second meshing element 3. The first meshing element 2 and the second meshing element 3 are parallel and spaced apart. Along the axial direction of the second meshing element 3, the first tooth assembly 21 and the second tooth assembly 31 are staggered. With this arrangement, when the first meshing element 2 and the second meshing element 3 rotate relative to the barrel 1, the material can be periodically divided by the first tooth assembly 21 and the second tooth assembly 31, and in this process, recombination and stretching are completed to achieve efficient solid-liquid mixing. Furthermore, since multiple first teeth 211 are spaced apart along the circumferential direction of the first meshing element 2 in the first tooth assembly 21, and multiple second teeth 311 are spaced apart along the circumferential direction of the second meshing element 3 in the second tooth assembly 31, when mixing high solid content solid particles with non-Newtonian liquid, the high solid content solid particles can be squeezed into the grooves between adjacent first teeth 211 or adjacent second teeth 311, and trigger high-frequency mechanical segmentation, recombination and stretching, ensuring that the solid particles are uniformly dispersed in the non-Newtonian fluid, thereby improving the mixing effect.

[0025] Continue to refer to Figures 1-6 In the first tooth assembly 21, there is a first tooth groove 212 between two adjacent first teeth 211. In the second tooth assembly 31, there is a second tooth groove 312 between two adjacent second teeth 311. When the first meshing element 2 and the second meshing element 3 rotate relative to the barrel 1, the first teeth 211 and the second tooth groove 312 are arranged facing each other along the axial direction of the first meshing element 2, and the second teeth 311 and the first tooth groove 212 are arranged facing each other along the axial direction of the second meshing element 3, thereby improving the material separation ability of the two meshing elements and further improving the mixing effect.

[0026] Continue to refer to Figures 1-6Along the circumferential direction of the first meshing element 2, the central angle corresponding to the tip of the first tooth 211 is smaller than the central angle corresponding to the root of the first tooth 211. The cross-section of the first tooth 211 has a fan-shaped structure, allowing material to be guided through the side of the first tooth 211, enabling the material to flow fully. Similarly, along the circumferential direction of the second meshing element 3, the central angle corresponding to the tip of the second tooth 311 is smaller than the central angle corresponding to the root of the second tooth 311. The cross-section of the second tooth 311 also has a fan-shaped structure, allowing material to be guided through the side of the second tooth 311, enabling the material to flow fully.

[0027] Continue to refer to Figures 1-6 The first tooth assembly 21 includes 8 to 12 first teeth 211, and the second tooth assembly 31 includes 8 to 12 second teeth 311. Optionally, the number of first teeth 211 in the first tooth assembly 21 is the same as the number of second teeth 311 in the second tooth assembly 31, and the multiple first teeth 211 are evenly arranged along the circumferential direction of the first meshing element 2, and the multiple second teeth 311 are evenly arranged along the circumferential direction of the second meshing element 3. In this embodiment, specifically, the first tooth assembly 21 includes 10 first teeth 211, and the second tooth assembly 31 includes 10 second teeth 311. In the first tooth assembly 21, the central angle between the centers of the top surfaces of two adjacent first teeth 211 is θ1, specifically 36°. In addition, along the circumferential direction of the first meshing element 2, the central angle corresponding to the tooth tip of the first tooth 211 is θ2, specifically 12°. The central angles corresponding to the two hypotenuses of the first tooth 211 are both θ3, specifically 6°. Correspondingly, the central angle corresponding to the tooth root of the first tooth 211 is θ4, specifically 24°. Furthermore, the central angle corresponding to the first tooth groove 212 between two adjacent first teeth 211 is θ5, specifically 12°. In the second tooth assembly 31, the shape parameters of the second tooth 311 are similar to those of the first tooth 211. Specifically, the central angle between the centers of the top surfaces of two adjacent second teeth 311 is also θ1, specifically 36°. Furthermore, along the circumferential direction of the second meshing element 3, the central angle corresponding to the tooth tip of the second tooth 311 is also θ2, specifically 12°. The central angle corresponding to the two hypotenuses of the second tooth 311 is also θ3, specifically 6°. Correspondingly, the central angle corresponding to the tooth root of the second tooth 311 is also θ4, specifically 24°. Additionally, the central angle corresponding to the second tooth groove 312 between two adjacent second teeth 311 is also θ5, specifically 12°. In other embodiments, the number of first teeth 211 in the first tooth assembly 21 and the number of second teeth 311 in the second tooth assembly 31 can be set to 8, 9, 11, or 12.

[0028] Continue to refer to Figures 1-6 The outer diameters of the first meshing element 2 and the second meshing element 3 are both R1. The height of the top surface of the first tooth 211 relative to the outer wall of the first meshing element 2 and the height of the top surface of the second tooth 311 relative to the outer wall of the second meshing element 3 are both R2, with 0.3≤R2 / R1≤0.6, so that the ratio of the height of the top surface of the first tooth 211 relative to the outer wall of the first meshing element 2 to the outer diameter of the first meshing element 2 is appropriate, and at the same time, the ratio of the height of the top surface of the second tooth 311 relative to the outer wall of the second meshing element 3 to the outer diameter of the second meshing element 3 is appropriate. Specifically, the ratio of R2 to R1 can be 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, or 0.6. In this embodiment, the outer diameters of both the first meshing element 2 and the second meshing element 3 are 12 mm. The height of the top surface of the first tooth 211 relative to the outer wall of the first meshing element 2 and the height of the top surface of the second tooth 311 relative to the outer wall of the second meshing element 3 are both 5.5 mm, and the ratio of R2 to R1 is approximately 0.46.

[0029] Another problem with existing twin-screw extruders is that excessive shear force and mechanical heat generation can easily lead to thermal degradation of materials or even explosion of oxidant particles.

[0030] In this regard, we will continue to refer to Figures 1-6 There is always a gap between the top surface of the first protrusion 211 and the outer wall of the second meshing element 3; there is always a gap between the top surface of the second protrusion 311 and the outer wall of the first meshing element 2. This arrangement allows the material to be contained in the gap between the top surface of the first protrusion 211 and the outer wall of the second meshing element 3 or the gap between the top surface of the second protrusion 311 and the outer wall of the first meshing element 2, fundamentally avoiding the safety hazards of strong shear and shear heat generated by small gaps, and improving safety performance.

[0031] Continue to refer to Figures 1-6When the first meshing element 2 and the second meshing element 3 rotate relative to the barrel 1, the minimum clearance between the top surface of the first tooth 211 and the outer wall of the second meshing element 3, and the minimum clearance between the top surface of the second tooth 311 and the outer wall of the first meshing element 2, are both d, where d ≤ 1 mm. Specifically, the value of d between the top surface of the first tooth 211 and the outer wall of the second meshing element 3, and between the top surface of the second tooth 311 and the outer wall of the first meshing element 2, can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, or 1 mm. In this embodiment, the value of d is specifically 0.5mm. Experiments show that this setting can ensure safety while enabling the material mixing mechanism to have a better material mixing effect.

[0032] Continue to refer to Figures 1-6 Along the axial direction of the second meshing element 3, there is a gap between the first tooth assembly 21 and the second tooth assembly 31, thereby forming an additional material flow channel between the first tooth assembly 21 and the second tooth assembly 31 on the basis of the above structure, so as to further avoid excessive local shear force.

[0033] Continue to refer to Figures 1-6 The material mixing mechanism also includes a meshing element drive structure. The output end of the meshing element drive structure has a first spline and a second spline. The first meshing element 2 is provided with a first spline hole 22 for connecting the first spline, and the second meshing element 3 is provided with a second spline hole 32 for connecting the second spline.

[0034] The meshing element drive structure includes a motor and two drive shafts. Both drive shafts are connected to the output end of the motor, and the two drive shafts rotate in the same direction. One drive shaft is provided with a first spline and is used to drive the first meshing element 2 to rotate, while the other drive shaft is provided with a second spline and is used to drive the second meshing element 3 to rotate. Specifically, one drive shaft is directly connected to the output end of the motor, and the two drive shafts are connected by a gear set, thereby indirectly connecting the other drive shaft to the output end of the motor. Optionally, the barrel 1 also has a first through hole 11 for the first spline to pass through and a second through hole 12 for the second spline to pass through.

[0035] This embodiment also provides an extruder, including the above-mentioned material mixing mechanism and a material conveying mechanism. The material conveying mechanism is used to convey the material to be mixed into the interior of the barrel 1 and to convey the mixed material inside the barrel 1 out of the barrel 1. In the material mixing mechanism, when the first meshing element 2 and the second meshing element 3 rotate relative to the barrel 1, the material can be periodically divided by the first tooth assembly 21 and the second tooth assembly 31, and in this process, reorganization and stretching are completed to achieve efficient solid-liquid mixing.

[0036] Example 1 A material mixing mechanism is provided, comprising a barrel 11 and the aforementioned first engaging element 2 and second engaging element 3. The barrel 11 has an inner diameter of 36 mm and a length of 32 mm. The center distance between the first engaging element 2 and the second engaging element 3 is 30 mm. The radii of the first engaging element 2 and the second engaging element 3 (excluding the first tooth 211 and the second tooth 311) are both 24 mm. The total length of the first engaging element 2 and the second engaging element 3 is 32 mm. The specific shape parameters of the first tooth 211 and the second tooth 311 are as follows: Figures 4-5 As specified above, the minimum gap between the top surface of the first tooth 211 and the outer wall of the second meshing element 3, the minimum gap between the top surface of the second tooth 311 and the outer wall of the first meshing element 2, and the gap between the first tooth assembly 21 and the second tooth assembly 31 along the axial direction of the second meshing element 3 are all 0.2 mm.

[0037] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 10 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0038] Example 2 A material mixing mechanism is provided, comprising a barrel 11 and the aforementioned first engaging element 2 and second engaging element 3. The barrel 11 has an inner diameter of 36 mm and a length of 32 mm. The center distance between the first engaging element 2 and the second engaging element 3 is 30 mm. The radii of the first engaging element 2 and the second engaging element 3 (excluding the first tooth 211 and the second tooth 311) are both 24 mm. The total length of the first engaging element 2 and the second engaging element 3 is 32 mm. The specific shape parameters of the first tooth 211 and the second tooth 311 are as follows: Figures 4-5As specified above, the minimum gap between the top surface of the first tooth 211 and the outer wall of the second meshing element 3, the minimum gap between the top surface of the second tooth 311 and the outer wall of the first meshing element 2, and the gap between the first tooth assembly 21 and the second tooth assembly 31 along the axial direction of the second meshing element 3 are all 0.2 mm.

[0039] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 20 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0040] Example 3 A material mixing mechanism is provided, comprising a barrel 11 and the aforementioned first engaging element 2 and second engaging element 3. The barrel 11 has an inner diameter of 36 mm and a length of 32 mm. The center distance between the first engaging element 2 and the second engaging element 3 is 30 mm. The radii of the first engaging element 2 and the second engaging element 3 (excluding the first tooth 211 and the second tooth 311) are both 24 mm. The total length of the first engaging element 2 and the second engaging element 3 is 32 mm. The specific shape parameters of the first tooth 211 and the second tooth 311 are as follows: Figures 4-5 As specified above, the minimum gap between the top surface of the first tooth 211 and the outer wall of the second meshing element 3, the minimum gap between the top surface of the second tooth 311 and the outer wall of the first meshing element 2, and the gap between the first tooth assembly 21 and the second tooth assembly 31 along the axial direction of the second meshing element 3 are all 0.2 mm.

[0041] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 30 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0042] Comparative Example 1 A material mixing mechanism is provided, comprising a barrel 1 and conventional twin-screw meshing elements. The barrel 1 has an inner diameter of 36 mm and a length of 32 mm. Two meshing elements are provided, each with multiple meshing blocks protruding from it. The multiple meshing blocks are spaced apart along the axial direction of the meshing elements. The center distance between the two meshing elements is 30 mm. The radius of the meshing elements (excluding the meshing blocks) is 24 mm. The staggered angle of the meshing blocks is 45°. The gaps between the screw and between the screw and the barrel 1 are both 0.2 mm. The length of both meshing elements is 32 mm.

[0043] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 10 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0044] Comparative Example 2 A material mixing mechanism is provided, comprising a barrel 1 and conventional twin-screw meshing elements. The barrel 1 has an inner diameter of 36 mm and a length of 32 mm. Two meshing elements are provided, each with multiple meshing blocks protruding from it. The multiple meshing blocks are spaced apart along the axial direction of the meshing elements. The center distance between the two meshing elements is 30 mm. The radius of the meshing elements (excluding the meshing blocks) is 24 mm. The staggered angle of the meshing blocks is 45°. The gaps between the screw and between the screw and the barrel 1 are both 0.2 mm. The length of both meshing elements is 32 mm.

[0045] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 20 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0046] Comparative Example 3 A material mixing mechanism is provided, comprising a barrel 1 and conventional twin-screw meshing elements. The barrel 1 has an inner diameter of 36 mm and a length of 32 mm. Two meshing elements are provided, each with multiple meshing blocks protruding from it. The multiple meshing blocks are spaced apart along the axial direction of the meshing elements. The center distance between the two meshing elements is 30 mm. The radius of the meshing elements (excluding the meshing blocks) is 24 mm. The staggered angle of the meshing blocks is 45°. The gaps between the screw and between the screw and the barrel 1 are both 0.2 mm. The length of both meshing elements is 32 mm.

[0047] The material used for mixing consists of high-solids-content solid particles and a non-Newtonian liquid, wherein the non-Newtonian fluid serves as the continuous phase. The feed mass flow rate is 0.002778 kg / s, and the density is 1372 kg / m³. 3 Solid particles were used as the dispersed phase, with an initial dispersed phase content of 50 vol% and a density of 1980 kg / m³. 3 The continuous phase and the dispersed phase were mechanically mixed at 30 rpm of the meshing element for 0.17 s. Shear stress, viscous dissipation power, and mixing effect were monitored during the mechanical mixing process.

[0048] Experiments were conducted on each of the above embodiments and comparative examples, and the shear stress, viscous dissipation power, and mixing effect were monitored. The solid-liquid mixing efficiency is shown in Table 1, the peak shear stress and volume average shear stress are shown in Table 2, and the maximum viscous dissipation power and volume average viscous dissipation power are shown in Table 3.

[0049] Table 1. Solid-liquid mixing efficiency of each embodiment and comparative example Table 2. Peak shear stress and volume average shear stress of each embodiment and comparative example Table 3. Maximum viscous dissipation power and volume-average viscous dissipation power of each embodiment and comparative example. Experiments show that, compared with the traditional twin-screw meshing element scheme, the scheme using the first meshing element 2 and the second meshing element 3 provided in this application has higher solid-liquid mixing efficiency, lower peak shear stress, lower volume average shear stress, lower maximum viscous dissipation power, and lower volume average viscous dissipation power.

[0050] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this invention is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-disclosed concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A material mixing mechanism, characterized in that, include: barrel (1); The first meshing element (2) is shaft-shaped and is disposed inside the barrel (1) and can rotate relative to the barrel (1). The outer peripheral wall of the first meshing element (2) is provided with a plurality of first tooth assemblies (21) spaced apart along the axial direction of the first meshing element (2). The first tooth assembly (21) includes a plurality of first teeth (211) spaced apart along the circumferential direction of the first meshing element (2). The second meshing element (3) is shaft-shaped and is disposed inside the barrel (1) and can rotate relative to the barrel (1). The rotation direction of the second meshing element (3) is the same as that of the first meshing element (2). The outer peripheral wall of the second meshing element (3) is provided with a plurality of second tooth assemblies (31) spaced apart along the axial direction of the second meshing element (3). The second tooth assembly (31) includes a plurality of second teeth (311) spaced apart along the circumferential direction of the second meshing element (3). The first meshing element (2) is parallel to and spaced apart from the second meshing element (3). Along the axial direction of the second meshing element (3), the first tooth assembly (21) and the second tooth assembly (31) are misaligned.

2. The material mixing mechanism according to claim 1, characterized in that, In the first tooth assembly (21), there is a first tooth groove (212) between two adjacent first teeth (211), and in the second tooth assembly (31), there is a second tooth groove (312) between two adjacent second teeth (311). When the first engagement element (2) and the second engagement element (3) rotate relative to the barrel (1), the first tooth (211) and the second tooth groove (312) are arranged opposite each other along the axial direction of the first engagement element (2), and the second tooth (311) and the first tooth groove (212) are arranged opposite each other along the axial direction of the second engagement element (3).

3. The material mixing mechanism according to claim 1, characterized in that, Along the circumferential direction of the first meshing element (2), the central angle corresponding to the tooth tip of the first tooth (211) is smaller than the central angle corresponding to the tooth root of the first tooth (211); along the circumferential direction of the second meshing element (3), the central angle corresponding to the tooth tip of the second tooth (311) is smaller than the central angle corresponding to the tooth root of the second tooth (311).

4. The material mixing mechanism according to claim 1, characterized in that, The first tooth assembly (21) includes 8 to 12 first teeth (211), and the second tooth assembly (31) includes 8 to 12 second teeth (311).

5. The material mixing mechanism according to claim 1, characterized in that, The outer diameters of the first meshing element (2) and the second meshing element (3) are both R1. The height of the top surface of the first tooth (211) relative to the outer wall of the first meshing element (2) and the height of the top surface of the second tooth (311) relative to the outer wall of the second meshing element (3) are both R2, and 0.3≤R2 / R1≤0.

6.

6. The material mixing mechanism according to any one of claims 1-5, characterized in that, There is always a gap between the top surface of the first tooth (211) and the outer wall of the second meshing element (3); there is always a gap between the top surface of the second tooth (311) and the outer wall of the first meshing element (2).

7. The material mixing mechanism according to claim 6, characterized in that, When the first meshing element (2) and the second meshing element (3) rotate relative to the barrel (1), the minimum gap between the top surface of the first tooth (211) and the outer wall of the second meshing element (3) and the minimum gap between the top surface of the second tooth (311) and the outer wall of the first meshing element (2) are both d, d≤1mm.

8. The material mixing mechanism according to any one of claims 1-5, characterized in that, Along the axial direction of the second meshing element (3), there is a gap between the first tooth assembly (21) and the second tooth assembly (31).

9. The material mixing mechanism according to any one of claims 1-5, characterized in that, It also includes a meshing element drive structure, the output end of which has a first spline and a second spline. The first meshing element (2) is provided with a first spline hole (22) for connecting the first spline, and the second meshing element (3) is provided with a second spline hole (32) for connecting the second spline.

10. An extruder, characterized in that, The material mixing mechanism as described in any one of claims 1-9 is further comprising a material conveying mechanism for conveying the material to be mixed into the interior of the barrel (1) and conveying the mixed material inside the barrel (1) out of the barrel (1).

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