Low-precipitation PBT (polybutylene terephthalate) resin extrusion molding device

Abstract

The invention discloses a low-precipitation PBT (Polybutylene Terephthalate) resin extrusion molding device, and aims to solve the resin precipitation phenomenon caused by low material conveying efficiency, non-uniform mixing and insufficient temperature control precision in the prior art. The device comprises a rotor compression assembly and a mixing extrusion assembly, a compression cavity with an approximately trilobal elliptical section and an eccentrically rotating rotor are arranged in the rotor compression assembly, and efficient compression and preliminary mixing of materials are achieved through dynamic sealing; the mixing and extruding assembly comprises a conveying pipe, a shaft rod, a plurality of rotary vane conveying paddles, a fixing strip and electric heating guide rings arranged at intervals in the axial direction, the conical spiral structures of the rotary vane conveying paddles are matched with the design of branch flow channels and axial flow channels of the fixing strip, efficient shunting, confluence and mixing of materials are achieved, and the electric heating guide rings have the independent temperature control function; the temperature can be adjusted in sections, local overheating or supercooling is avoided, and the phenomenon of resin precipitation is effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of resin extrusion molding, in particular to a low-precipitation PBT resin extrusion molding device. Background Art

[0002] At present, the extrusion molding of PBT resin mainly adopts traditional screw extrusion equipment. Traditional equipment usually consists of a single screw or twin screw conveying mechanism, a heating system and an extrusion die. The material is conveyed forward under the rotation of the screw and heated to a molten state by the heating system for molding. In order to improve the performance of the resin, functional additives are added to the molten resin through a simple side feeding device in some processes. Traditional screw extrusion equipment relies on the change in the depth of the screw thread to compress the material and controls the melt temperature through the heating system in the barrel.

[0003] Although traditional screw extruders are widely used in the molding of PBT resins, they have the following obvious defects in material conveying, mixing and temperature control: The compression capacity of traditional screw structures is limited. The material is compressed in the area where the screw depth changes, which leads to poor compression uniformity, especially when extruding high-viscosity materials or mixed materials containing additives, which can easily lead to unstable conveying. Traditional screw equipment is difficult to form an effective dynamic seal, and materials may leak and reflux during the conveying process, further reducing the compression and conveying efficiency. In traditional screw equipment, materials are mainly mixed by the shearing effect generated by the rotation of the screw, but the shear force in the mixing area is unevenly distributed, especially after the addition of additives, it is difficult to achieve full distribution of materials and additives, affecting the quality of the final product.

[0004] The traditional heating system mainly controls the overall temperature by heating the barrel, and cannot independently regulate different conveying areas, resulting in uneven heating. When processing low-precipitation PBT resin, the insufficient temperature control accuracy can easily lead to resin degradation or precipitation due to local overheating during the heating process, reducing product performance.

[0005] In view of this, the existing problems are studied and improved, and a low precipitation PBT resin extrusion molding device is provided to solve the current problems. The purpose is to solve the problems and improve the practical value through this technology. Summary of the invention

[0006] The present invention aims to solve one of the technical problems existing in the prior art or related technology.

[0007] To this end, the technical solution adopted by the present invention is: a low precipitation PBT resin extrusion molding device, comprising: Rotor compression assembly: The rotor compression assembly is provided with a compression chamber and a rotor rotatably mounted inside the compression chamber, a feed hopper and an additive filling port are fixedly mounted on the surface of the rotor compression assembly, the rotor is installed in the compression chamber and driven to rotate by the main shaft, and the material is transported from the feed hopper to the compression chamber for compression through the rotation of the rotor; Mixing extrusion assembly: including a conveying pipe, a shaft, a plurality of rotary blade conveying paddles, a fixing bar and an electric heating guide ring. One end of the conveying pipe is connected to the inside of the compression chamber. A reduction motor is provided inside the conveying pipe to drive the rotating shaft to rotate, thereby driving the rotary blade conveying paddle to convey and mix the materials. Electric heating guide rings: arranged at intervals along the axial direction of the conveying pipe, and fixed to the inner side of the conveying pipe by fixing strips, cooperate with the rotary blade conveying paddle to form an outer flow channel and an inner flow channel, which are used to divert, converge and mix the materials, and heat the materials at the same time.

[0008] In a preferred example, the present invention can be further configured as follows: Optimized design of compression chamber and rotor: The compression chamber is an elliptical cross-section cavity with a three-leaf shape, and its inner wall is a smooth curved surface, which is used to cooperate with the eccentric rotation of the rotor to form a dynamic seal and improve the compression effect of the material. The rotor as a whole is a cylinder formed by the intersection of two ellipses, and an eccentric shaft hole is installed in the center for connecting the main shaft rod. The surface of the main shaft rod is provided with a crankshaft rod, and an eccentric counterweight block is fixedly installed on the surface of the crankshaft rod to balance the eccentric torque generated during the rotation process and improve the stability of the rotation.

[0009] Enhanced design of mixing extrusion components: The rotary blade conveying paddle is a conical spiral structure, set on the shaft, used to apply moderate shear force to the material during the conveying process to enhance the mixing effect. The branch flow channel and axial flow channel formed by the fixed bar and the rotary blade conveying paddle can achieve the diversion and confluence of materials during the conveying process, further improving the mixing uniformity.

[0010] Independently temperature-controlled electric heating guide rings: Several electric heating guide rings are arranged at intervals along the axial direction of the conveying pipe and can achieve independent temperature control. By accurately controlling the temperature in sections, local overheating or overcooling can be avoided, reducing the risk of resin precipitation.

[0011] The beneficial effects achieved by the present invention are: 1. In the present invention, the design of the compression chamber and the rotor structure can achieve dynamic sealing, and complete the staged compression and transportation of the material in the working chamber, significantly improve the compression efficiency of the material, and carry out high-efficiency transportation of additives and extrudates. The eccentric rotation thereof improves the compression effect and thus achieves a large torque extrusion effect.

[0012] 2. In the present invention, the conical spiral structure design of the rotary blade conveying paddle, the branch flow channel and axial flow channel design formed by the fixed bar and the rotary blade conveying paddle, and the arc-shaped opposing design of the outer flow channel and the inner flow channel on the outside of the electric heating guide ring enable the material to be diverted and converged in alternating motion, further improve the uniformity of the mixing, and enhance the mixing effect of the material and the additive.

[0013] 3. In the present invention, the independent temperature control design of the electric heating guide ring can adjust the temperature of the material regionally along the axial direction of the conveying pipe, and accurately control the temperature in sections to avoid local overheating or overcooling, thereby effectively inhibiting the precipitation of PBT resin caused by uneven temperature during the extrusion process. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of the exploded structure of a rotor compression assembly according to an embodiment of the present invention; Figure 3 A schematic diagram of the internal structure of a rotor compression assembly according to an embodiment of the present invention; Figure 4 A schematic diagram of the cross-sectional structure of a mixed extrusion assembly according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of a fixing bar, a shaft rod and an electric heating guide ring according to an embodiment of the present invention; Figure 6 A schematic diagram of the structure of a fixing strip and an electric heating guide ring according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the installation structure of a rotary blade conveying paddle according to an embodiment of the present invention.

[0015] Reference numerals: 100, rotor compression assembly; 110, feed hopper; 120, main shaft rod; 130, rotor; 101, compression chamber; 102, additive filling port; 103, sealing strip; 121, crankshaft rod; 122, eccentric counterweight; 200, mixing extrusion assembly; 210, conveying pipe; 220, fixing bar; 230, shaft rod; 240, electric heating guide ring; 250, rotary blade conveying paddle; 300, reduction motor. DETAILED DESCRIPTION

[0016] To make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in combination with specific implementations and with reference to the accompanying drawings. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0017] It is to be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention.

[0018] The following is combined with Figure 1-Figure 7 A low precipitation PBT resin extrusion molding device provided by some embodiments of the present invention is described.

[0019] Implementation method 1: basic structure and working principle A low precipitation PBT resin extrusion molding device, the main structure of which includes: a rotor compression component 100, a mixing extrusion component 200 and an electric heating guide ring 240.

[0020] 1. Rotor compression assembly 100 The rotor compression assembly 100 includes a compression chamber 101 and a rotor 130. The compression chamber 101 is an elliptical cross-section chamber that is approximately three-leaf shaped, and the inner wall surface is smooth, which is used to cooperate with the eccentric rotation of the rotor 130 to achieve dynamic sealing. The rotor 130 is a cylinder formed by the intersection of two ellipses, and an eccentric shaft hole is installed in the center for connecting the main shaft rod 120. One end of the main shaft rod 120 is connected to the crankshaft rod 121, and an eccentric counterweight block 122 is fixed on the surface of the crankshaft rod 121 to balance the eccentric torque generated during the eccentric rotation of the rotor, thereby improving the stability of the equipment operation and the compression effect.

[0021] The main shaft 120 is connected to the external driving structure, and the rotor 130 is driven to rotate by the main shaft 120 to complete the dynamic compression of the material in the compression chamber 101. During the compression process, the material enters the compression chamber 101 from the feed hopper 110, and the additive is added through the additive filling port 102. The two are preliminarily mixed during the rotor compression process, and the sealing strip 103 in the compression chamber 101 is used to achieve the sealing separation of the chamber to prevent material leakage.

[0022] 2. Mixing extrusion component 200 The mixing extrusion assembly 200 includes a conveying pipe 210, a shaft 230, a plurality of rotary blade conveying paddles 250, a fixing bar 220 and an electric heating guide ring 240. One end of the conveying pipe 210 is connected to the compression chamber 101 for receiving the material output from the compression chamber 101, and the other end can be connected to an extrusion head or a molding die for extrusion molding.

[0023] The shaft 230 is driven to rotate by the reduction motor 300, driving a number of rotary blade conveying paddles 250 to work. The rotary blade conveying paddles 250 are conical spiral structures and are evenly spaced and installed on the shaft 230. Under the action of the rotary blade conveying paddles 250, the material generates moderate shear force during the conveying process, thereby enhancing the mixing effect. A fixing bar 220 is also provided inside the conveying pipe 210. The fixing bar 220 cooperates with the rotary blade conveying paddles 250 to form a branch flow channel and an axial flow channel. The material alternately moves between the branch flow channel and the axial flow channel, further improving the mixing uniformity of the material and the additive.

[0024] 3. Electric heating guide ring 240 The electric heating guide rings 240 are arranged at intervals along the axial direction of the conveying pipe 210 and fixed to the inner side of the conveying pipe 210 by the fixing strips 220. An outer flow channel is formed on the outer side of each electric heating guide ring 240, and an inner flow channel is formed between the rotary blade conveying paddle 250. The outer flow channel and the inner flow channel are designed to be opposite to each other in an arc shape. During the material conveying process, the material is diverted into the outer flow channel, diverted through the outer flow channel, and then merged into the inner flow channel to achieve sufficient diversion and confluence mixing. The electric heating guide ring 240 has an independent temperature control function, which can accurately adjust the temperature according to the material characteristics of different areas of the conveying pipe, prevent local overheating or overcooling, and effectively reduce the precipitation of PBT resin during processing.

[0025] Implementation method 2: Improved multi-stage compression hybrid structure On the basis of the first embodiment, this embodiment further optimizes the structural design of the rotor compression assembly 100 and the mixing extrusion assembly 200 to meet the mixing requirements of higher viscosity resin materials and complex additives.

[0026] 1. Improvement of rotor compression assembly In this embodiment, the compression chamber 101 maintains a three-leaf elliptical cross-section design, but multiple annular sealing strips 103 are added inside to further improve the sealing performance of the compression chamber. The rotor 130 is driven to rotate by the main shaft 120, and the crankshaft 121 and the eccentric counterweight 122 provide stable eccentric torque support.

[0027] 2. Enhancement of temperature control system The number and distribution density of the electric heating guide rings 240 are further optimized to achieve more accurate temperature gradient control in different areas of the conveying pipe 210. By setting up an intelligent temperature control system, the material temperature is monitored in real time, and the working state of the electric heating guide rings is dynamically adjusted, thereby ensuring that the material maintains the optimal temperature range during the entire conveying process.

[0028] 3. Workflow After the material enters the compression chamber 101 from the feed hopper 110, it is transported by the multi-stage spiral structure of the rotary blade conveying paddle 250. During the conveying process, the material passes through the fixed bar 220 and the electric heating guide ring 240 for multiple diversions and confluences, and at the same time completes efficient mixing and precise temperature control, and finally is output from the conveying pipe 210 in the form of high-quality extrudates.

[0029] The working principle and use process of the present invention: The low precipitation PBT resin extrusion molding device of the present invention is mainly composed of a rotor compression assembly 100 and a mixing extrusion assembly 200, and the two parts work in coordination to achieve efficient transportation, compression, mixing and molding of low precipitation PBT resin. The specific working principle is as follows: Compression and preliminary mixing principle of the rotor compression assembly: Compression chamber 101: The compression chamber adopts an elliptical cross-section design that is approximately three-leaf shaped, which matches the eccentric rotation trajectory of the rotor 130 to form a dynamic sealing effect. The rotor 130 rotates eccentrically under the drive of the crankshaft rod 121, and the sliding of its outer surface and the cooperation of the sealing strip 103 compress the material in stages.

[0030] Material conveying and preliminary mixing: The raw material enters the compression chamber 101 from the feed hopper 110, and functional additives are added through the additive filling port 102. Under the eccentric rotation of the rotor 130, the material is compressed and conveyed to the mixing extrusion assembly 200, and preliminary mixing with the additive is achieved.

[0031] Efficient mixing and conveying principle of mixing extrusion components: Rotary blade conveying paddle 250: The rotary blade conveying paddle 250 in the mixing and extruding assembly is designed in a conical spiral shape, and drives the material forward through the rotation of the shaft 230. During the conveying process, the rotary blade conveying paddle 250 generates a moderate shear force to further mix the material.

[0032] Diversion and confluence: The fixed bar 220 cooperates with the rotary blade conveying paddle 250 to form an outer flow channel and an inner flow channel. The material moves alternately in the outer flow channel and the inner flow channel, further realizing diversion and confluence mixing to ensure uniform distribution of the material and additives.

[0033] Independently temperature-controlled electric heating guide ring 240: The electric heating guide ring is arranged at intervals along the axial direction of the conveying pipe 210 and has an independent temperature control function. It can perform precise temperature control on the material in sections according to the needs of the conveying area to prevent local overheating or overcooling, thereby reducing the risk of precipitation of PBT resin.

[0034] Extrusion molding: The uniformly mixed material with moderate temperature is extruded from the end of the conveying pipe 210 and enters the subsequent molding process such as mold molding, wire drawing, injection molding, etc. to complete the production of the resin product.

[0035] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0036] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A low precipitation PBT resin extrusion molding device, characterized in that: include: A rotor compression assembly (100), wherein a compression chamber (101) and a rotor (130) rotatably mounted inside the compression chamber (101) are provided inside the rotor compression assembly (100); a feed hopper (110) and an additive filling port (102) are fixedly mounted on the surface of the rotor compression assembly (100); the rotor (130) is mounted in the compression chamber (101) and driven to rotate by a main shaft (120); and the rotation of the rotor (130) transports materials from the feed hopper (110) to the compression chamber (101) for compression; The mixing extrusion assembly (200) comprises a conveying pipe (210), a shaft (230), a plurality of rotary blade conveying paddles (250), a fixing bar (220) and an electric heating guide ring (240), wherein one end of the conveying pipe (210) is in communication with the interior of the compression chamber (101), and a reduction motor (300) is provided inside the conveying pipe (210) for driving the rotating shaft (230) to rotate, thereby driving the rotary blade conveying paddles (250) to convey and mix materials; The electric heating guide rings (240) are arranged at intervals along the axial direction of the conveying pipe (210), and are fixed to the inner side of the conveying pipe (210) via the fixing strips (220), and cooperate with the rotary blade conveying paddles (250) to form an outer flow channel and an inner flow channel, and are used to divide and merge materials, and to heat the materials at the same time.

2. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The compression chamber (101) is an elliptical cross-section chamber that is approximately three-leaf shaped, and its inner wall is a smooth curved surface that is used to cooperate with the eccentric rotation of the rotor (130). A sealing strip (103) that is in sliding contact with the surface of the rotor (130) is provided on the inner side of the compression chamber (101).

3. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The rotor (130) is a cylindrical body formed by the intersection of two ellipses, and an eccentric shaft hole is installed at the center of the cylindrical body for connecting the main shaft rod (120). The surface of the main shaft rod (120) is provided with a crankshaft rod (121), and the crankshaft rod (121) is sleeved on the inner side of the rotor (130) for driving the rotor (130) to rotate eccentrically. An eccentric counterweight block (122) is fixedly installed on the surface of the crankshaft rod (121) to balance the eccentric torque generated during the rotation process and improve the stability of the rotation.

4. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The plurality of electric heating guide rings (240) can be independently temperature-controlled to adjust the temperature of the material in a regional manner along the axial direction of the conveying pipe (210), thereby reducing the risk of resin precipitation.

5. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The rotary blade conveying paddle (250) is arranged on the shaft (230) in a conical spiral shape, and is used to generate a moderate shear force on the material during the conveying process to enhance the mixing effect.

6. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The fixing strips (220) are multiple and evenly distributed in the circumferential direction, and are used to fix the electric heating guide ring (240); in the axial direction of the conveying pipe (210), the fixing strips (220) cooperate with the rotary blade conveying paddle (250) to form multiple branch flow channels and axial flow channels, and the material alternately moves between the branch flow channels and the axial flow channels through the rotation of the rotary blade conveying paddle (250), thereby achieving efficient mixing of the material.

7. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The outer flow channel outside the electric heating guide ring (240) is arc-shaped and opposite to the inner flow channel of the electric heating guide ring (240); during the conveying movement, the material is diverted to the outer flow channel and then merged into the inner flow channel again, thereby improving the mixing effect of the material.

8. A low precipitation PBT resin extrusion molding device according to claim 1, characterized in that: The number of the electric heating guide rings (240) and the rotary blade conveying paddles (250) is several and they are evenly spaced and distributed along the straight line direction of the surface of the shaft (230).

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