An extruder
By setting multiple feed ports and a movable carriage sleeve system at the top of the extruder, the problems of functional material degradation and uneven mixing caused by the fixed feeding position of traditional extruders are solved, realizing flexible material addition and uniform mixing, and improving equipment adaptability and mixing effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- FOSHAN SHUNDE NAN KAI NEW MATERIAL
- Filing Date
- 2025-11-26
- Publication Date
- 2026-06-30
AI Technical Summary
Traditional extruders cannot flexibly adjust the feeding position according to the melting progress of the main material and the characteristics of the functional material, resulting in the degradation or uneven mixing of the functional material in a high-temperature environment, making it difficult to adapt to diverse material combinations and process requirements.
Multiple second feed ports are equidistantly spaced along the axial direction at the top of the extrusion cylinder. Combined with a sliding movable carriage and movable sleeve, functional materials can be flexibly added at different melting stages. The feeding position is precisely controlled by adjusting the motor and guiding system to ensure uniform mixing.
It achieves uniform mixing of functional materials and main materials, avoids degradation of functional materials, improves the adaptability of equipment to different production processes, and ensures the quality stability of the mixture.
Smart Images
Figure CN224426410U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of plastic processing equipment, specifically to an extruder. Background Technology
[0002] In industrial fields such as plastics processing and polymer material molding, extruders are core equipment for melting, mixing, and molding materials, and are widely used in the production of pipes, sheets, profiles, and other products. As the industry's requirements for product performance continue to increase, it is often necessary to add functional materials to the main material to optimize product characteristics. For example, adding flame retardants can improve the fire resistance of products, adding antioxidants can slow down the degradation rate of products, or adding nano-sized easily dispersible materials can enhance the mechanical properties of products.
[0003] In traditional extrusion processes, functional materials and main materials are typically fed into the extruder together through a single feed port, or added at a fixed position at the front of the extruder. However, different functional materials have significantly different characteristics: flame retardants are mostly heat-sensitive substances, which are prone to degradation when exposed to high temperatures for extended periods, leading to a decrease in their flame-retardant effect; if easily dispersible materials are mixed with the main material too early, they may agglomerate during the melting process of the main material due to uneven stress, affecting the uniformity of mixing; at the same time, different main materials have different melting rates and melting stages, making it difficult for a fixed feeding position to adapt to diverse material combinations and process requirements. Utility Model Content
[0004] This invention provides an extruder that solves the problem in the prior art that extruders cannot flexibly adjust the feeding position according to the melting progress of the main material and the characteristics of the functional material.
[0005] An extruder includes a frame, an extrusion mechanism, and a feeding mechanism. The extrusion mechanism includes an extrusion barrel, a screw, and a heating assembly. The extrusion barrel is horizontally fixedly connected to the frame. The screw is rotatably disposed inside the extrusion barrel. A first feed port and a second feed port are provided at the top of the extrusion barrel. The heating assembly is disposed on the extrusion barrel. Multiple second feed ports are provided and are equidistantly spaced along the axis of the extrusion barrel. The feeding mechanism includes a first hopper, a second hopper, a movable slide, and a movable sleeve. The first hopper is fixedly connected to the port of the first feed port. The movable slide is slidably connected to the frame along the axis of the extrusion barrel. The second hopper is fixedly connected to the movable slide and is located above the second feed port. The top of the movable sleeve is slidably connected to the second hopper, and the bottom of the movable sleeve is slidably connected to the second feed port.
[0006] According to one embodiment of the present invention, the feeding mechanism further includes a guide shaft and a lead screw. The guide shaft and the lead screw are both vertically connected to the movable slide. One side of the movable sleeve is provided with a guide hole that slides with the guide shaft, and the other side of the movable sleeve is provided with a threaded hole that mates with the lead screw.
[0007] According to one embodiment of the present invention, the feeding mechanism further includes an anti-detachment ring, which is coaxially and fixedly connected to the guide shaft, and the outer diameter of the anti-detachment ring is larger than the inner diameter of the guide hole.
[0008] According to one embodiment of the present invention, the feeding mechanism further includes an adjusting motor, which is fixedly connected to the movable slide, and the output end of the adjusting motor is fixedly connected to the lead screw on the same axis.
[0009] According to one embodiment of the present invention, the feeding mechanism further includes a sealing assembly. Several sets of sealing assemblies are provided and are respectively arranged at the ports corresponding to the second feed inlets. The sealing assembly includes a limiting frame, a limiting rod, and a movable door plate. The limiting frame is fixedly connected to the extrusion cylinder. The limiting rod is horizontally fixedly connected to the limiting frame. Two movable door plates are provided and are symmetrically arranged at the ports of the second feed inlets. The side of the movable door plate is provided with a limiting hole that slides with the limiting rod. The bottom of the movable door plate abuts against the top of the second feed inlet.
[0010] According to one embodiment of the present invention, the sealing assembly further includes a spring, wherein a plurality of springs are provided and are respectively wound around the outside of the corresponding limiting rod, one end of the spring abuts against the movable door panel, and the other end of the spring abuts against the limiting frame.
[0011] According to one embodiment of the present invention, the top of the movable door panel is provided with an inclined guide surface.
[0012] According to one embodiment of the present invention, the extrusion mechanism further includes a drive wheel, a driven wheel, a timing belt, and a drive motor. The drive wheel is rotatably connected to the frame, the driven wheel is coaxially fixedly connected to the screw, the timing belt is disposed between the drive wheel and the driven wheel, the drive motor is fixedly connected to the frame, and the output end of the drive motor is coaxially fixedly connected to the drive wheel.
[0013] According to one embodiment of the present invention, the feeding mechanism further includes an electric guide rail and a movable slide block. The electric guide rail is horizontally fixedly connected to the frame, the movable slide block is slidably connected to the electric guide rail, and the movable slide frame is fixedly connected to the movable slide block.
[0014] According to one embodiment of the present invention, the inner top of the movable sleeve is slidably connected to the outer bottom of the second hopper, and the outer bottom of the movable sleeve is slidably connected to the inner top of the second feed inlet.
[0015] The advantages of this utility model compared to the prior art are:
[0016] Multiple secondary feed ports are equidistantly spaced along the axial direction at the top of the extrusion barrel. Combined with a movable slide that slides along the frame and a dockable movable sleeve, operators can flexibly select the addition position of the functional material based on the melting progress of the main material and the characteristics of the functional material. Without disassembling or modifying the equipment, the mid-stage feeding position can be switched for different extrusion processes. This solves the problem of traditional fixed single-feed-port extruders having an unadjustable feeding position, making it difficult to adapt to the mixing needs of various materials, and significantly improves the equipment's adaptability to different production processes. At the same time, it avoids the functional material from being degraded due to prolonged heating after entering the extrusion barrel too early, while ensuring the uniformity of the mixing between the functional material and the main material.
[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:
[0019] Figure 1 This is a three-dimensional structural diagram of an extruder.
[0020] Figure 2 This is a three-dimensional structural diagram of the extrusion mechanism in this utility model.
[0021] Figure 3 This is a three-dimensional structural diagram of the feeding mechanism in this utility model.
[0022] Figure 4 This is a three-dimensional structural cross-sectional view of the feeding mechanism in this utility model.
[0023] The reference numerals in the figures include:
[0024] 1. Frame; 2. Extrusion mechanism; 3. Feeding mechanism; 4. Extrusion cylinder; 5. First feed inlet; 6. Second feed inlet; 7. First hopper; 8. Second hopper; 9. Movable slide; 10. Movable sleeve; 11. Guide shaft; 12. Lead screw; 13. Anti-detachment ring; 14. Adjusting motor; 15. Sealing assembly; 16. Limiting frame; 17. Limiting rod; 18. Movable door panel; 19. Spring; 20. Guide surface; 21. Driving wheel; 22. Driven wheel; 23. Synchronous belt; 24. Drive motor; 25. Electric guide rail; 26. Movable slide. Detailed Implementation
[0025] The specific embodiments of this utility model are described in detail below, but it should be understood that the protection scope of this utility model is not limited to the specific embodiments.
[0026] like Figures 1 to 4 As shown, an extruder includes a frame 1, an extrusion mechanism 2, and a feeding mechanism 3. The extrusion mechanism 2 includes an extrusion cylinder 4, a screw, and a heating assembly. The extrusion cylinder 4 is horizontally fixedly connected to the frame 1. The screw is rotatably disposed inside the extrusion cylinder 4. The top of the extrusion cylinder 4 has a first feed port 5 and a second feed port 6. The heating assembly is disposed on the extrusion cylinder 4. Multiple second feed ports 6 are provided and are equidistantly spaced along the axial direction of the extrusion cylinder 4. The feeding mechanism 3 includes a first hopper 7, a second hopper 8, a movable slide 9, and a movable sleeve 10. The first hopper 7 is fixedly connected to the port of the first feed port 5. The movable slide 9 is slidably connected to the frame 1 along the axial direction of the extrusion cylinder 4. The second hopper 8 is fixedly connected to the movable slide 9 and is located above the second feed port 6. The top of the movable sleeve 10 is slidably connected to the second hopper 8, and the bottom of the movable sleeve 10 is slidably connected to the second feed port 6.
[0027] During operation, the operator feeds the main material (such as plastic substrate granules) into the first hopper 7. The main material enters the extrusion cylinder 4 through the first feed port 5. At the same time, the screw rotates under the drive of an external power source, conveying the main material forward along the axis of the extrusion cylinder 4. During this process, the extrusion cylinder 4 heats the main material through a heating component, causing the main material to gradually melt from a solid state into a plasticized melt, laying the foundation for subsequent mixing of functional materials.
[0028] During the mid-stage functional material addition phase, multiple second feed ports 6 are equidistantly spaced at the top of the extrusion cylinder 4 along its axial direction. The movable slide 9 in the feeding mechanism 3 slides along the axis of the extrusion cylinder 4 with the frame 1. The second hopper 8 is fixed on the movable slide 9 and positioned above the second feed ports 6. The movable sleeve 10 slides between the bottom of the second hopper 8 and the top of the second feed ports 6. According to the addition requirements of the functional material (flame retardant or easily dispersible material), the operator can push the movable slide 9 along the frame 1, causing the second hopper 8 to move synchronously above the target second feed port 6. Then, the position of the movable sleeve 10 is adjusted to precisely align the bottom of the second hopper 8 with the top of the target second feed port 6, forming a closed feeding channel. At this point, the flame retardant or easily dispersible material is added to the second hopper 8. The material enters the extrusion cylinder 4 through the movable sleeve 10 and the second feed port 6, where it encounters the pre-plasticized main material melt within the extrusion cylinder 4. Under the rotating shearing action of the screw, the functional material and the main material melt are fully mixed. If the position of the functional material needs to be adjusted (such as to adapt to the main material at different melting stages), simply slide the movable slide 9 again, move the second hopper 8 to another second feed port 6, and reconnect the movable sleeve 10 to complete the adjustment.
[0029] During the mixing and extrusion stage, the melt containing the functional materials continues to be conveyed forward along the extrusion barrel 4 under the continuous rotation of the screw. During this process, the shearing force of the screw and the heating effect of the extrusion barrel 4 further eliminate the composition and temperature gradients in the melt, ensuring that the functional materials are uniformly dispersed in the main material melt. Finally, the uniformly mixed melt is conveyed to the discharge end of the extrusion barrel 4.
[0030] Multiple second feed ports 6 are equidistantly spaced along the axial direction at the top of the extrusion cylinder 4. These, along with a movable slide 9 that slides along the frame 1 and a dockable movable sleeve 10, allow operators to flexibly select the addition position of functional materials based on the melting progress of the main material and the characteristics of the functional materials (such as the heat resistance of flame retardants and the mixing requirements of easily dispersible materials). Without disassembling or modifying the equipment, the mid-stage feeding position can be switched for different extrusion processes. This solves the problem of traditional fixed single-feed-port extruders having an unadjustable feeding position, making it difficult to adapt to the mixing needs of various materials, and significantly improves the equipment's adaptability to different production processes. Simultaneously, it avoids the functional materials from being degraded due to prolonged heating after premature entry into the extrusion cylinder 4, while ensuring the uniform mixing of the functional materials and the main material.
[0031] According to one embodiment of the present invention, the feeding mechanism 3 further includes a guide shaft 11 and a lead screw 12. The guide shaft 11 and the lead screw 12 are both vertically connected to the movable slide 9. One side of the movable sleeve 10 is provided with a guide hole that slides with the guide shaft 11, and the other side of the movable sleeve 10 is provided with a threaded hole that mates with the lead screw 12.
[0032] When it is necessary to adjust the connection between the movable sleeve 10 and the second hopper 8 and the second feed inlet 6, the operator can rotate the lead screw 12. Since the lead screw 12 is threadedly engaged with the threaded hole of the movable sleeve 10, the rotation of the lead screw 12 will be converted into linear motion of the movable sleeve 10 in the vertical direction. At the same time, the guide shaft 11 passes through the guide hole of the movable sleeve 10, constraining the movement trajectory of the movable sleeve 10 and preventing it from deviating or tilting during vertical movement. By rotating the lead screw 12 to control the raising and lowering of the movable sleeve 10, the connection gap between it and the bottom of the second hopper 8 and the top of the second feed inlet 6 can be precisely adjusted to ensure the formation of a closed feeding channel and prevent material leakage or scattering.
[0033] According to one embodiment of this utility model, the feeding mechanism 3 further includes an anti-detachment ring 13, which is coaxially and fixedly connected to the guide shaft 11, and the outer diameter of the anti-detachment ring 13 is larger than the inner diameter of the guide hole. When the movable sleeve 10 slides vertically along the guide shaft 11, the anti-detachment ring 13 is always located at the end of the guide shaft 11 away from the movable slide 9. If the operator excessively rotates the lead screw 12 during the adjustment process, causing the movable sleeve 10 to move away from the movable slide 9, the anti-detachment ring 13 will physically block the movable sleeve 10, preventing the movable sleeve 10 from falling off the guide shaft 11 due to excessive sliding, ensuring that the movable sleeve 10 always maintains a cooperative state with the guide shaft 11 and the lead screw 12, and does not affect subsequent docking operations.
[0034] According to one embodiment of this utility model, the feeding mechanism 3 further includes an adjusting motor 14, which is fixedly connected to the movable slide 9. The output end of the adjusting motor 14 is coaxially fixedly connected to the lead screw 12. When it is necessary to adjust the position of the movable sleeve 10, the operator does not need to manually rotate the lead screw 12. Instead, by starting the adjusting motor 14, the adjusting motor 14 drives the lead screw 12 to rotate, thereby driving the movable sleeve 10 to vertically rise and fall along the guide shaft 11. The adjusting motor 14 can achieve speed adjustment through frequency conversion control, thereby controlling the lifting speed of the movable sleeve 10 and precisely controlling the number of rotations of the lead screw 12, realizing quantitative adjustment of the lifting distance of the movable sleeve 10 and ensuring the consistency of the docking position.
[0035] According to one embodiment of the present invention, the feeding mechanism 3 further includes a sealing assembly 15. The sealing assembly 15 is provided in several groups and is respectively provided at the port of the corresponding second feed port 6. The sealing assembly 15 includes a limiting frame 16, a limiting rod 17 and a movable door plate 18. The limiting frame 16 is fixedly connected to the extrusion cylinder 4. The limiting rod 17 is horizontally fixedly connected to the limiting frame 16. Two movable door plates 18 are provided and are symmetrically arranged at the port of the second feed port 6. The side of the movable door plate 18 is provided with a limiting hole that slides with the limiting rod 17. The bottom of the movable door plate 18 abuts against the top of the second feed port 6.
[0036] When the movable sleeve 10 is not connected to a certain second feed port 6, the movable door plate 18 abuts against the top of the second feed port 6, closing the second feed port 6 to prevent the high-temperature melt or hot gas in the extrusion cylinder 4 from overflowing from the idle second feed port 6; when the movable sleeve 10 needs to connect to the second feed port 6, it pushes the movable door plate 18 to slide to both sides along the limiting rod 17 to open the second feed port 6, and forms a closed feeding channel after the connection is completed; when the movable sleeve 10 leaves, the movable door plate 18 is reset to close the second feed port 6 again.
[0037] According to one embodiment of the present invention, the sealing assembly 15 further includes a spring 19, wherein a plurality of springs 19 are provided and are respectively wound around the outside of the corresponding limiting rod 17, one end of the spring 19 abuts against the movable door panel 18, and the other end of the spring 19 abuts against the limiting frame 16.
[0038] When the movable door panel 18 is pushed to slide to both sides, it compresses the spring 19, causing the spring 19 to store elastic potential energy. When the movable sleeve 10 moves away, the spring 19 releases its elastic potential energy, pushing the movable door panel 18 back to its original position along the limit rod 17, quickly closing the second feed port 6. The elastic force of the spring 19 always acts on the movable door panel 18, ensuring that the movable door panel 18 is in close contact with the top of the second feed port 6 in a non-butt-fitting state, improving the sealing effect. Even under slight vibration of the equipment, it can prevent the sealing failure caused by the displacement of the movable door panel 18.
[0039] According to one embodiment of this utility model, the top of the movable door panel 18 is provided with an inclined guide surface 20. When the movable sleeve 10 descends to connect with the second feed port 6, the bottom of the movable sleeve 10 will first contact the inclined guide surface 20 on the top of the movable door panel 18. As the sleeve continues to descend, the guide surface 20 will decompose the vertical downward force of the sleeve into a horizontal component force that pushes the movable door panel 18 to slide to both sides, making the movable door panel 18 slide open more smoothly along the limiting rod 17. Without the need for operators to adjust the position of the door panel, the movable sleeve 10 can automatically push open the movable door panel 18 through the guide surface 20 to complete the docking preparation.
[0040] According to one embodiment of the present invention, the extrusion mechanism 2 further includes a drive wheel 21, a driven wheel 22, a timing belt 23, and a drive motor 24. The drive wheel 21 is rotatably connected to the frame 1, the driven wheel 22 is coaxially fixedly connected to the screw, the timing belt 23 is disposed between the drive wheel 21 and the driven wheel 22, the drive motor 24 is fixedly connected to the frame 1, and the output end of the drive motor 24 is coaxially fixedly connected to the drive wheel 21.
[0041] During operation, the drive motor 24 is started, and its output drives the drive wheel 21 to rotate. The drive wheel 21 transmits power to the driven wheel 22 via the synchronous belt 23, which in turn drives the screw to rotate synchronously, realizing the conveying and mixing of the main material and the functional material. The drive motor 24 can be adjusted by frequency conversion control, thereby controlling the rotation speed of the screw to adapt to the conveying and mixing requirements of materials with different viscosities. For example, the speed can be reduced when processing high-viscosity melts to avoid excessive pressure, while the speed can be increased when processing low-viscosity materials to ensure conveying efficiency.
[0042] According to one embodiment of the present invention, the feeding mechanism 3 further includes an electric guide rail 25 and a movable slide 26. The electric guide rail 25 is horizontally fixedly connected to the frame 1, the movable slide 26 is slidably connected to the electric guide rail 25, and the movable carriage 9 is fixedly connected to the movable slide 26.
[0043] When the position of the second hopper 8 needs to be adjusted to align with different second feed inlets 6, the electric guide rail 25 is activated. The electric guide rail 25 drives the movable slide 26 to slide horizontally along the guide rail. The movable slide 26 drives the movable carriage 9 to move synchronously with the second hopper 8 until the second hopper 8 moves above the target second feed inlet 6. The electric guide rail 25 can achieve precise positioning of the second hopper 8 by setting the moving distance and speed, without requiring the operator to manually push the movable carriage 9.
[0044] According to one embodiment of this utility model, the inner top side of the movable sleeve 10 is slidably connected to the outer bottom side of the second hopper 8, and the outer bottom side of the movable sleeve 10 is slidably connected to the inner top side of the second feed inlet 6. When the movable sleeve 10 is engaged, its inner top side wraps around the outer bottom side of the second hopper 8, and its outer bottom side is embedded in the inner top side of the second feed inlet 6, forming a nested fit structure. This fit increases the contact area between the movable sleeve 10 and the second hopper 8 and the second feed inlet 6, while reducing dead corners where materials stagnate in the feeding channel, and preventing materials from accumulating and clumping at the fit gaps.
[0045] The above-disclosed embodiments are only a few specific examples of the present utility model. However, the embodiments of the present utility model are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the protection scope of the present utility model.
Claims
1. An extruder, characterized in that, The device includes a frame (1), an extrusion mechanism (2), and a feeding mechanism (3). The extrusion mechanism (2) includes an extrusion cylinder (4), a screw, and a heating assembly. The extrusion cylinder (4) is horizontally fixedly connected to the frame (1). The screw is rotatably disposed inside the extrusion cylinder (4). The top of the extrusion cylinder (4) has a first feed port (5) and a second feed port (6). The heating assembly is disposed on the extrusion cylinder (4). Multiple second feed ports (6) are provided and are equidistantly spaced along the axial direction of the extrusion cylinder (4). The feeding mechanism (3) includes a first feed port (5) and a second feed port (6). The machine includes a hopper (7), a second hopper (8), a movable slide (9), and a movable sleeve (10). The first hopper (7) is fixedly connected to the port of the first feed inlet (5). The movable slide (9) is slidably connected to the frame (1) along the axis of the extrusion cylinder (4). The second hopper (8) is fixedly connected to the movable slide (9) and located above the second feed inlet (6). The top of the movable sleeve (10) is slidably connected to the second hopper (8), and the bottom of the movable sleeve (10) is slidably connected to the second feed inlet (6).
2. The extruder as described in claim 1, characterized in that, The feeding mechanism (3) also includes a guide shaft (11) and a lead screw (12). The guide shaft (11) and the lead screw (12) are both vertically connected to the movable slide (9). One side of the movable sleeve (10) is provided with a guide hole that slides with the guide shaft (11), and the other side of the movable sleeve (10) is provided with a threaded hole that mates with the lead screw (12).
3. An extruder as described in claim 2, characterized in that, The feeding mechanism (3) also includes an anti-detachment ring (13), which is coaxially fixedly connected to the guide shaft (11), and the outer diameter of the anti-detachment ring (13) is larger than the inner diameter of the guide hole.
4. An extruder as described in claim 2, characterized in that, The feeding mechanism (3) also includes an adjusting motor (14), which is fixedly connected to the movable slide (9), and the output end of the adjusting motor (14) is fixedly connected to the lead screw (12) on the same axis.
5. An extruder as described in claim 1, characterized in that, The feeding mechanism (3) also includes a sealing assembly (15). The sealing assembly (15) is provided in several sets and is respectively provided at the port of the corresponding second feed port (6). The sealing assembly (15) includes a limiting frame (16), a limiting rod (17) and a movable door plate (18). The limiting frame (16) is fixedly connected to the extrusion cylinder (4). The limiting rod (17) is fixedly connected to the limiting frame (16) in a horizontal state. There are two movable door plates (18) and they are symmetrically arranged at the port of the second feed port (6). The side of the movable door plate (18) is provided with a limiting hole that slides with the limiting rod (17). The bottom of the movable door plate (18) abuts against the top of the second feed port (6).
6. An extruder as described in claim 5, characterized in that, The sealing assembly (15) also includes a spring (19), which is provided in several parts and is respectively wrapped around the outside of the corresponding limiting rod (17). One end of the spring (19) abuts against the movable door panel (18), and the other end of the spring (19) abuts against the limiting frame (16).
7. An extruder as described in claim 5, characterized in that, The top of the movable door panel (18) is provided with an inclined guide surface (20).
8. An extruder as described in claim 1, characterized in that, The extrusion mechanism (2) further includes a drive wheel (21), a driven wheel (22), a timing belt (23), and a drive motor (24). The drive wheel (21) is rotatably connected to the frame (1), the driven wheel (22) is coaxially fixedly connected to the screw, the timing belt (23) is disposed between the drive wheel (21) and the driven wheel (22), the drive motor (24) is fixedly connected to the frame (1), and the output end of the drive motor (24) is coaxially fixedly connected to the drive wheel (21).
9. An extruder as described in claim 1, characterized in that, The feeding mechanism (3) also includes an electric guide rail (25) and a movable slide (26). The electric guide rail (25) is horizontal and fixedly connected to the frame (1). The movable slide (26) is slidably connected to the electric guide rail (25). The movable carriage (9) is fixedly connected to the movable slide (26).
10. An extruder as described in claim 1, characterized in that, The inner top of the movable sleeve (10) is slidably connected to the outer bottom of the second hopper (8), and the outer bottom of the movable sleeve (10) is slidably connected to the inner top of the second feed inlet (6).