Multi-screw devolatilization extruder capable of independently controlling revolution and rotation

Abstract

The invention relates to the technical field of devolatilization extruders, and discloses a multi-screw devolatilization extruder capable of independently controlling revolution and rotation, which comprises a revolution motor, a rotation motor, couplings, a machine barrel and a gear box, the front end of the machine barrel is connected with the machine head; a gear in the gear box is connected with a plurality of devolatilization screw rods and a revolution screw rod, and the devolatilization screw rods and the revolution screw rod are positioned in the machine barrel. Through revolution of the revolution screw rod and rotation of the devolatilization screw rod, the high-viscosity polymer can be fully mixed, and the devolatilization efficiency is improved. The devolatilization screw rod adopts a variable-interval thread design, and the devolatilization effect and the conveying efficiency are further improved by adjusting the thread interval.

Description

Technical Field

[0001] This invention relates to the field of devouring extruder technology, specifically to a multi-screw devouring extruder whose revolution and rotation can be controlled independently. Background Technology

[0002] In the production of high-viscosity polymers, residual volatile substances can affect the quality and performance of the final product. To remove these volatile substances, a devolatilization process is typically required.

[0003] Existing devolatilization equipment, such as single-screw extruders and twin-screw extruders, while achieving some devolatilization effect, presents several challenges when processing high-viscosity polymers. For example, single-screw extruders exhibit poor mixing and low devolatilization efficiency; twin-screw extruders have complex structures and high maintenance costs. Therefore, there is an urgent need to develop a multi-screw devolatilization extruder that offers high-efficiency devolatilization, efficient mixing, and a simplified structure. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a multi-screw devouring extruder whose revolution and rotation can be controlled independently. Through innovative design of the screw motion mode, thread structure, and vacuum distribution, efficient devouring, efficient mixing, and stable continuous conveying are achieved.

[0005] To achieve the above objectives, the technical solution of the present invention is: a multi-screw devouring extruder with independently controllable revolution and rotation, comprising a revolution motor, a rotation motor, a coupling, a barrel, and a gearbox. The revolution motor and the rotation motor are respectively connected to gears inside the gearbox via the coupling. The rear end of the barrel is connected to the gearbox, and the front end is connected to the die head. The gears inside the gearbox are connected to devouring screws and revolution screws. There are several devouring screws, and the devouring screws and revolution screws are located inside the barrel.

[0006] Furthermore, the devouring screw consists of eight screws evenly distributed around a central point.

[0007] Furthermore, the barrel is provided with a feed hole and several vacuum holes above it.

[0008] Furthermore, a circular fixed plate is provided inside the barrel, and both the devouring screw and the revolution screw pass through the circular fixed plate and are connected to the circular fixed plate through bearings. A sealing ring is provided between the devouring screw and the revolution screw and the circular fixed plate.

[0009] Furthermore, the devouring screw is provided with a variable pitch thread, with a smaller thread pitch near the vacuum hole and a larger thread pitch away from the vacuum hole.

[0010] Furthermore, the cross-sectional shape of the revolution screw is polygonal.

[0011] The beneficial effects of this invention are: 1) This invention achieves thorough mixing of high-viscosity polymers and improves devolatilization efficiency by using the revolution of the revolution screw and the rotation of the devolatilization screw.

[0012] 2) The devouring screw adopts a variable pitch thread design, which further improves the devouring effect and conveying efficiency by adjusting the thread pitch.

[0013] 3) The independent control system for the revolution motor and the rotation motor allows for flexible adjustment of the revolution and rotation speeds, optimizing the devolatilization process.

[0014] 4) The multi-screw structure increases the contact area between the material and the screw, improving heat transfer efficiency and devolatilization efficiency. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the structure of the devouring screw and the revolution screw of the present invention; Figure 3 This is a schematic diagram of the devouring screw structure of the present invention; Figure 4 This is a partial structural diagram of the orbiting screw of the present invention.

[0016] In the diagram: 1. Revolutionary motor; 2. Rotary motor; 3. Coupling; 4. Barrel; 5. Head; 6. Gearbox; 7. Vacuum port; 8. Feed port; 9. Deviation screw; 10. Revolutionary screw; 11. Sealing ring; 12. Bearing. Detailed Implementation

[0017] The gearbox of this invention was purchased from Zhejiang Shuanghuan Transmission Machinery Co., Ltd., and is an SH series planetary reducer.

[0018] Example:

[0019] like Figures 1 to 4As shown, a multi-screw devouring extruder with independently controllable revolution and rotation includes a revolution motor 1, a rotation motor 2, a coupling 3, a barrel 4, and a gearbox 6. The revolution motor 1 and the rotation motor 2 are respectively connected to gears inside the gearbox 6 via the coupling 3. The coupling 3 transmits power and can absorb a certain amount of vibration and deviation. The rear end of the barrel 4 is connected to the gearbox 6, and the front end is connected to the die head 5; the die head 5 is used to extrude the devoured material into shape. The gears inside the gearbox 6 are connected to devouring screws 9 and revolution screws 10. There are eight devouring screws 9 evenly distributed around the revolution screw 10. The devouring screws 9 are arranged around the revolution screw 10 to form a multi-screw structure, which can increase the mixing and heat transfer area of ​​the material. The devouring screws 9 and revolution screws 10 are located inside the barrel 4. The gearbox 6 realizes the distribution and speed change of power, enabling the devouring screws 9 to rotate on their own axis and the revolution screws 10 to revolve around the revolution.

[0020] The barrel 4 has a feed port 8 and three vacuum ports 7 at its top. The vacuum ports 7 are used to connect a vacuum pump to achieve depressurized devolatilization. A circular fixed plate is fixedly installed inside the barrel 4. The devolatilization screw 9 and the revolution screw 10 both pass through the circular fixed plate and are connected and supported by the circular fixed plate through bearings 12 to ensure stable rotation. Sealing rings 11 are provided between the devolatilization screw 9 and the revolution screw 10 and the circular fixed plate to prevent material leakage.

[0021] The devolatilization screw 9 is provided with a variable pitch thread. The thread pitch is smaller near the vacuum hole 7 to enhance the devolatilization effect, and the thread pitch is larger away from the vacuum hole 7 to facilitate material conveying.

[0022] The cross-sectional shape of the revolution screw 10 is polygonal to increase the contact area with the material and improve the mixing effect.

[0023] Working Principle: The high-viscosity polymer enters the barrel 4 through the feed port 8. The devolatilization screw 9 rotates via the self-rotating motor 2, while the revolution screw 10 revolves via the revolution motor 1. The gearbox 6 independently controls the rotation speed of the devolatilization screw 9 and the revolution speed of the revolution screw 10, ensuring thorough mixing of the material. Under the rotation of the devolatilization screw 9, the material is conveyed to the vicinity of the vacuum port 7. Due to the small thread pitch, the material stays there for a longer time, which is beneficial for the escape of volatile substances. The vacuum pump creates a vacuum inside the barrel through the vacuum port 7, further lowering the boiling point of the volatile substances and promoting the devolatilization process. The fully devolatilized material is extruded from the die head 5.

[0024] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications may be made without departing from the technical solutions described in the claims.

[0025] In the description of this invention, it should be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

Claims

1. A multi-screw devouring extruder with independently controllable revolution and rotation, characterized in that: The machine includes a revolution motor (1), a rotation motor (2), a coupling (3), a barrel (4), and a gearbox (6). The revolution motor (1) and the rotation motor (2) are connected to the gears inside the gearbox (6) through the coupling (3). The rear end of the barrel (4) is connected to the gearbox (6), and the front end is connected to the machine head (5). The gear inside the gearbox (6) is connected to a detached screw (9) and a revolution screw (10). There are several detached screws (9), and the detached screws (9) and the revolution screws (10) are located inside the barrel (4).

2. The multi-screw devouring extruder with independently controllable revolution and rotation as described in claim 1, characterized in that: The devouring screw (9) consists of eight evenly distributed revolving screws (10) around the center.

3. The multi-screw devouring extruder with independently controllable revolution and rotation as described in claim 1, characterized in that: The barrel (4) is provided with a feed hole (8) and several vacuum holes (7) above it.

4. The multi-screw devouring extruder with independently controllable revolution and rotation as described in claim 1, characterized in that: The barrel (4) is provided with a circular fixed plate inside. The devouring screw (9) and the revolution screw (10) both pass through the circular fixed plate and are connected to the circular fixed plate through a bearing (12). A sealing ring (11) is provided between the devouring screw (9) and the revolution screw (10) and the circular fixed plate.

5. The multi-screw devouring extruder with independently controllable revolution and rotation as described in claim 1, characterized in that: The devouring screw (9) is provided with a variable pitch thread. The thread pitch is smaller when it is close to the vacuum hole (7) and larger when it is far away from the vacuum hole (7).

6. The multi-screw devouring extruder with independently controllable revolution and rotation as described in claim 1, characterized in that: The cross-sectional shape of the revolution screw (10) is polygonal.

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