Ultra-long small-taper double-barrel screw extruder for plastic recovery

Abstract

The invention relates to the technical field of exhaust of extruders, and discloses a super-long small-taper double-barrel screw extruder for plastic recovery. Materials are conveyed forwards through the interior of the machine barrel, the heater heats the interior of the machine barrel, the materials are fused in the machine barrel, then the fused materials are extruded out of the other end of the machine barrel, meanwhile, the moving part is driven to move, the moving part moves in an 8-shaped track in the machine barrel, and the moving part drives the shifting rod to move; according to the invention, the stirring rod is arranged in the machine barrel, so that the stirring rod turns over materials in the machine barrel to help bubbles in the materials to escape, the molten materials in the machine barrel are turned over and stirred, the molten materials are turned over at the position of the exhaust port to assist the molten materials in exhausting, and the exhausting efficiency is improved within a specific exhausting time period; the content of bubbles contained in a molten material is reduced, the influence of the bubbles on extrusion molding of the material is avoided, and the production quality of the extruder is improved.

Description

Technical Field

[0001] The invention relates to the technical field of extruder exhaust, in particular to an ultra-long small-taper twin-barrel screw extruder for plastic recycling. Background Art

[0002] The principle of the extruder is to use a screw of a specific shape to rotate in a heated barrel. The surface of the screw is provided with working sections with different texture shapes. Each working section has a different function. The plastic sent from the hopper is squeezed forward to melt the plastic evenly. The plastic is extruded into continuous plastic layers of various shapes required through the machine head and molds of different shapes.

[0003] In existing extruders, such as Chinese patent application CN113492513A, a twin-screw extruder element is provided, and a plurality of groups of axially arranged pin groups are provided on the screw ribs of the twin-screw extruder, which can increase the number of fluid flow line bundles, so that the material can be continuously separated, merged, crossed or changed in direction during the flow process, and the material can be effectively divided, the material flow condition can be changed, and the mixing ability of the screw can be enhanced.

[0004] However, there are still the following problems: due to the influence of the size of the exhaust port, the exhaust time period for the bubbles in the melted material in the barrel is relatively short, and it is very easy for bubbles to remain in the molten material and affect the extrusion molding of subsequent materials, thereby reducing the production quality of the extruder. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides an extra-long small-taper twin-barrel screw extruder for plastic recycling, which has the function of stirring the molten material in the barrel, so that the molten material is turned over at the exhaust port to assist the molten material in exhausting, thereby improving the exhaust efficiency within a specific exhaust time period, reducing the bubble content in the molten material, avoiding the influence of bubbles on the extrusion molding of the material, and improving the production quality of the extruder. It solves the problem that due to the influence of the size of the exhaust port, the exhaust time period for the bubbles in the material after melting in the barrel to remain is short, it is very easy for bubbles to exist in the molten material and affect the extrusion molding of subsequent materials, thereby reducing the production quality of the extruder.

[0006] To achieve the above object, the present invention provides the following technical solution: an ultra-long small-taper twin-barrel screw extruder for plastic recycling, comprising a base, an extrusion mechanism arranged on the base, and an auxiliary mechanism arranged on the extrusion mechanism, the extrusion mechanism comprising a heater and a barrel, the heater is fixedly mounted on the base, the heater is used to melt the material, the barrel is arranged on the base, the barrel passes through the heating area of ​​the heater, and the barrel is used to transport and process the material;

[0007] The auxiliary mechanism includes a moving part and a lever. The moving part is movably arranged in the barrel and is located in the exhaust area of ​​the extruder. The shape of the moving part is matched with the shape of the inner wall of the barrel. A plurality of the levers are fixedly installed on the inner ring wall surface of the moving part. The levers are evenly distributed on the moving part. The length of the lever is matched with the length of the exhaust area of ​​the extruder, and the lever moves synchronously with the moving part.

[0008] Preferably, the extrusion mechanism also includes a machine cover plate, the machine cover plate is fixedly mounted on the base, a barrel bracket is arranged inside the machine cover plate, the barrel bracket is fixedly mounted on the base, the barrel bracket passes through both ends of the machine cover plate, a feed hopper is fixedly mounted on the machine cover plate, the bottom end of the feed hopper passes through the wall of the machine cover plate, the bottom end of the feed hopper passes through the barrel bracket, the bottom end of the feed hopper is connected to the barrel, and the barrel passes through the heating area of ​​the heater.

[0009] Preferably, a main motor is fixedly mounted on the base, a coupling is fixedly mounted on the shaft of the main motor, a gear set is provided on the base, one end of the gear set is power-connected to the coupling, the other end of the gear set extends into the barrel, a first screw is provided in the barrel, a second screw is provided in the barrel, the first screw and the second screw are threadably adapted, the gear set is power-connected to the first screw, and the gear set is power-connected to the second screw, so that the first screw and the second screw rotate relative to each other.

[0010] Preferably, the barrel is provided with a plurality of exhaust ports, the exhaust ports are located in the exhaust area of ​​the extruder, the exhaust ports are communicated with the interior of the machine cover plate, a discharge port is fixedly installed at one end of the barrel, the discharge port is communicated with the barrel, the discharge port passes through the barrel bracket, and the discharge port passes through the machine cover plate.

[0011] Preferably, the interior of the barrel comprises a plurality of regions, a feeding section is provided at one end of the interior of the barrel, the feeding section is used to convey the material, a preplasticizing section is provided inside the barrel, the preplasticizing section is adjacent to the feeding section, the preplasticizing section is used to heat and soften the material, a mixing section a is provided inside the barrel, the mixing section a is adjacent to the preplasticizing section, the mixing section a is used to mix and shear the material, a compression section a is provided inside the barrel, the compression section a is adjacent to the mixing section a, the compression section a is used to compact the material, a exhaust section a is provided inside the barrel, the exhaust section a is adjacent to the compression section a, the exhaust section a is used to exhaust the material, a mixing section b is provided inside the barrel, the mixing section b is adjacent to the exhaust section a, the mixing section b is used to mix and shear the material again, A compression section b is provided inside the barrel, and the compression section b is adjacent to the mixing section b. The compression section b is used to compact the material again. A degassing section b is provided inside the barrel, and the degassing section b is adjacent to the compression section b. The degassing section b is used to degas the material again. An extrusion section is provided inside the barrel, and the extrusion section is adjacent to the degassing section b. The extrusion section is used to extrude the material. The first screw and the second screw are both fixed with a plurality of first shearing teeth of a tooth type at the mixing section a, and the first shearing teeth on the first screw and the second screw are meshed with each other. The first screw and the second screw are both fixed with screw ridges a, second shearing teeth of a tooth type, screw ridges b and screw ridges c in sequence at the mixing section b, and the second shearing teeth on the first screw and the second screw are meshed with each other.

[0012] Preferably, the first screw and the second screw have the same structure and are both small conical screws, whose diameters gradually decrease along the material conveying direction, whose diameters at the end away from the discharge port are D1, and whose diameters at the end close to the discharge port are D2, whose lengths are L, whose cone angles are α, tanα=(D1-D2) / 2 / L, tanα is 0.001~0.009, and whose aspect ratios are A, A=L / D2, and A is 30~40.

[0013] Preferably, the auxiliary mechanism also includes a first accommodating slot, a plurality of the first accommodating slots are provided in the barrel, the first accommodating slots are symmetrically distributed on both sides of the exhaust port, the first accommodating slot is adjacent to the exhaust port, the shape of the first accommodating slot is the same as the shape of the inner wall of the barrel, a first annular rail is fixedly installed in the first accommodating slot, the shape of the first annular rail is the same as the shape of the first accommodating slot, the size of the first annular rail is matched with the size of the first accommodating slot, the first annular rail is sealed with the barrel, the moving part is movably installed on the first annular rail, the shape of the moving part is the same as the first annular rail, the moving part passes through the wall of the first annular rail, and the moving part is sealed with the first annular rail.

[0014] Preferably, a toothed belt is fixedly mounted on the outer ring of the movable member, the shape of the toothed belt is the same as that of the movable member, the toothed belt passes through the barrel bracket, a plurality of auxiliary gears are rotatably mounted on the barrel bracket, the auxiliary gears are meshed with the toothed belt, and a first traction wheel is fixedly mounted on the shaft of the auxiliary gear.

[0015] Preferably, a servo motor is fixedly mounted on the base, the servo motor is located inside the machine cover plate, a second traction wheel is fixedly mounted on the shaft of the servo motor, and a belt is tensioned between the second traction wheel and the first traction wheel.

[0016] Preferably, a second accommodating groove is opened in the barrel, and the shape of the second accommodating groove is the same as the shape of the inner wall of the barrel. A second annular rail is fixedly installed on the second accommodating groove, and the shape of the second annular rail is the same as the shape of the second accommodating groove. A protective collar is movably installed on the inner ring of the second annular rail, and the shape of the protective collar is the same as that of the second annular rail. A plurality of ball rods are arranged between the protective collar and the second annular rail, and the ball rods are evenly distributed between the protective collar and the second annular rail.

[0017] Compared with the prior art, the present invention provides an ultra-long small-taper twin-screw extruder for plastic recycling, which has the following beneficial effects:

[0018] 1. The ultra-long small-taper twin-barrel screw extruder for plastic recycling first feeds the material into one end of the barrel, conveys the material forward from the inside of the barrel, starts the heater, heats the inside of the barrel, melts the material inside the barrel, and then extrude the molten material from the other end of the barrel. At the same time, the moving part is driven to move, so that the moving part moves in an "8"-shaped trajectory inside the barrel, and the moving part drives the lever to move, so that the lever flips the material in the barrel, thereby assisting the material to flip in the exhaust area to help the bubbles in the material escape, thereby forming a stirring action for the molten material in the barrel, and flipping the molten material at the exhaust port to assist the molten material in exhausting, thereby improving the exhaust efficiency within a specific exhaust time period, reducing the bubble content in the molten material, avoiding the influence of bubbles on the extrusion molding of the material, and improving the production quality of the extruder.

[0019] 2. The ultra-long small-taper twin-barrel screw extruder for plastic recycling, through the arrangement of the first accommodating notch and the first annular rail, enables the auxiliary mechanism to be better installed inside the barrel, thereby improving the stability of the extruder operation.

[0020] 3. The extra-long small-taper twin-barrel screw extruder for plastic recycling has a protective collar. When the first screw or the second screw contacts the protective collar, the first screw or the second screw drives the protective collar to move on the second annular rail, so that the first screw and the second screw will not generate a lot of friction with the inner wall of the barrel, and the ball rod reduces the friction between the protective collar and the second annular rail, so that the friction contact between the screw and the barrel is reduced, thereby increasing the service life of the screw and the barrel. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the extruder of the present invention;

[0022] Figure 2 It is a schematic diagram of the structure of the extrusion mechanism of the present invention;

[0023] Figure 3 This is a schematic diagram of the structural distribution of the feed hopper of the present invention;

[0024] Figure 4 It is an exploded schematic diagram of the structural distribution of the barrel, the first screw and the second screw of the present invention;

[0025] Figure 5 It is a plan view schematic diagram of the distribution of the working area inside the barrel of the present invention;

[0026] Figure 6 It is a schematic diagram of the auxiliary mechanism structure of the present invention;

[0027] Figure 7 This is a schematic diagram of the belt structure distribution of the present invention;

[0028] Figure 8 It is a schematic diagram of the structure distribution of the lever of the present invention;

[0029] Fig. 9 This is a schematic diagram of the structure distribution at the second receiving notch of the present invention;

[0030] Fig.10 This is a schematic diagram of the internal structure distribution of the second annular track of the present invention;

[0031] Fig.11 It is a schematic diagram of a unified plane identification of the first screw and the second screw of the present invention.

[0032] In the figure: 1, base; 2, extrusion mechanism; 21, machine cover plate; 22, barrel support; 23, feed hopper; 24, heater; 25, main motor; 26, coupling; 27, gear set; 28, barrel; 29, first screw; 210, second screw; 211, exhaust port; 212, discharge port; 213, feed section; 214, pre-plasticization section; 215, mixing section a; 216, compression section a; 217, exhaust section a; 218, mixing Refining section b; 219, compression section b; 220, exhaust section b; 221, extrusion section; 3, auxiliary mechanism; 31, first receiving slot; 32, first annular rail; 33, moving part; 34, lever; 35, toothed belt; 36, auxiliary gear; 37, first traction wheel; 38, servo motor; 39, second traction wheel; 310, belt; 311, second receiving slot; 312, second annular rail; 313, protective collar; 314, ball rod. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] As introduced in the background technology, there are deficiencies in the prior art. In order to solve the above technical problems, the present application proposes an extra-long small-taper twin-barrel screw extruder for plastic recycling.

[0035] Example 1

[0036] In a typical implementation of the present application, Figure 1-Figure 2As shown, an ultra-long small-taper twin-barrel screw extruder for plastic recycling includes a base 1, an extrusion mechanism 2 arranged on the base 1, and an auxiliary mechanism 3 arranged on the extrusion mechanism 2. The extrusion mechanism 2 includes a heater 24 and a barrel 28. The heater 24 is fixedly installed on the base 1, and the heater 24 is used to melt the material. The base 1 is provided with a barrel 28, and the barrel 28 passes through the heating area of ​​the heater 24, and the barrel 28 is used to transport and process the material.

[0037] The auxiliary mechanism 3 includes a moving part 33 and a lever 34. The moving part 33 is movably arranged in the barrel 28. The moving part 33 is located in the exhaust area of ​​the extruder. The shape of the moving part 33 is adapted to the shape of the inner wall of the barrel 28. A plurality of levers 34 are fixedly installed on the inner ring wall surface of the moving part 33. The levers 34 are evenly distributed on the moving part 33. The length of the levers 34 is adapted to the length of the exhaust area of ​​the extruder. The levers 34 move synchronously with the moving part 33.

[0038] Specifically, the inner shape of the barrel 28 is an "8"-shaped structure, and the shape of the moving member 33 is an "8"-shaped structure.

[0039] When using the present invention:

[0040] First, the material is fed into one end of the barrel 28, and the material is transported forward from the inside of the barrel 28, and the heater 24 is started. The heater 24 heats the inside of the barrel 28 so that the material melts inside the barrel 28, and then the molten material is extruded from the other end of the barrel 28. At the same time, the moving member 33 is driven to move, so that the moving member 33 moves in an "8"-shaped trajectory inside the barrel 28, and the moving member 33 drives the lever 34 to move, so that the lever 34 flips the material in the barrel 28, thereby assisting the material to flip in the exhaust area to help the bubbles in the material escape, thereby forming a stirring action for the molten material in the barrel, and the molten material is flipped at the exhaust port to assist the molten material to exhaust, thereby improving the exhaust efficiency within a specific exhaust time period, reducing the bubble content in the molten material, avoiding the bubbles from affecting the extrusion molding of the material, and improving the production quality of the extruder.

[0041] Example 2

[0042] like Figure 3-Figure 5As shown, the difference from the above embodiment is that the extrusion mechanism 2 also includes a machine cover plate 21, the machine cover plate 21 is fixedly mounted on the base 1, a barrel bracket 22 is arranged in the machine cover plate 21, the barrel bracket 22 is fixedly mounted on the base 1, the barrel bracket 22 passes through both ends of the machine cover plate 21, a feed hopper 23 is fixedly mounted on the machine cover plate 21, the bottom end of the feed hopper 23 passes through the wall of the machine cover plate 21, the bottom end of the feed hopper 23 passes through the barrel bracket 22, the bottom end of the feed hopper 23 is connected to the barrel 28, and the barrel 28 passes through the heating area of ​​the heater 24.

[0043] Furthermore, a main motor 25 is fixedly mounted on the base 1, a coupling 26 is fixedly mounted on the shaft of the main motor 25, a gear set 27 is provided on the base 1, one end of the gear set 27 is power-connected to the coupling 26, the other end of the gear set 27 extends into the barrel 28, a first screw 29 is provided in the barrel 28, a second screw 210 is provided in the barrel 28, the first screw 29 and the second screw 210 are threadably adapted, the gear set 27 is power-connected to the first screw 29, the gear set 27 is power-connected to the second screw 210, so that the first screw 29 and the second screw 210 rotate relative to each other.

[0044] Furthermore, a plurality of exhaust ports 211 are provided on the barrel 28, and the exhaust ports 211 are located in the exhaust area of ​​the extruder. The exhaust ports 211 are communicated with the interior of the machine cover plate 21, and a discharge port 212 is fixedly installed at one end of the barrel 28, and the discharge port 212 is communicated with the barrel 28, and the discharge port 212 passes through the barrel bracket 22, and the discharge port 212 passes through the machine cover plate 21.

[0045] Furthermore, the interior of the barrel 28 includes multiple areas. A feeding section 213 is provided at one end of the barrel 28, and the feeding section 213 is used to transport materials. A preplasticizing section 214 is provided inside the barrel 28, and the preplasticizing section 214 is adjacent to the feeding section 213. The preplasticizing section 214 is used to heat and soften the materials. A mixing section a215 is provided inside the barrel 28, and the mixing section a215 is adjacent to the preplasticizing section 214. The mixing section a215 is used to mix and shear the materials. A compression section a216 is provided inside the barrel 28, and the compression section a216 is adjacent to the mixing section a215. The compression section a216 is used to compact the materials.

[0046] Furthermore, an exhaust section a217 is provided inside the barrel 28, and the exhaust section a217 is adjacent to the compression section a216. The exhaust section a217 is used to exhaust the material. A mixing section b218 is provided inside the barrel 28, and the mixing section b218 is adjacent to the exhaust section a217. The mixing section b218 is used to mix and shear the material again. A compression section b219 is provided inside the barrel 28, and the compression section b219 is adjacent to the mixing section b218. The compression section b219 is used to compact the material again. An exhaust section b220 is provided inside the barrel 28, and the exhaust section b220 is adjacent to the compression section b219. The exhaust section b220 is used to exhaust the material again. An extrusion section 221 is provided inside the barrel 28, and the extrusion section 221 is adjacent to the exhaust section b220. The extrusion section 221 is used to extrude the material.

[0047] Among them, the feeding section 213: The main function is to convey materials and prevent material backflow. The screw in this section is similar to the conveying section of a single-screw extruder, which smoothly conveys materials such as plastic particles from the hopper to the inside of the extruder to prepare for subsequent processing;

[0048] Pre-plasticization section 214: Preliminary heating and softening of plastic raw materials, stirring and heating to fully mix the raw materials to ensure stable product quality and consistent performance, and fully melt and homogenize the materials through heat transfer and friction shear. In this section, the material begins to gradually change from a solid state to a molten state, providing conditions for the next step of mixing and processing. Heat transfer means heating in this section, and friction shear is achieved through the screw threads;

[0049] Mixing section a215: Mixing is performed by the mutual meshing of the first shearing teeth of the tooth shape, which can fully mix and shear the materials, so that different material components are fully mixed and reach a uniform state;

[0050] Compression section a216: The compression section after the mixing section further compacts the material. After mixing, the material may still be relatively loose. The compression section applies pressure to the material through the action of the screw and other components to compact it, making the material denser and exhausting the air in the material to prepare for the subsequent exhaust section. During the compression process, the material is subjected to higher pressure and appropriate shear force, which helps to better disperse;

[0051] Exhaust section a217: When the material is sent to the exhaust section under the conveyance of the screw, the gas in the material (such as water vapor formed by evaporation of water, air entrained in the raw materials, etc.) will be discharged under vacuum or normal pressure. The thread distribution gap of the exhaust section will be relatively large. The larger thread gap can provide sufficient escape space and channel for the gas, so that the gas can be smoothly separated from the material and discharged out of the extruder through the opening of the exhaust section;

[0052] Mixing section b218: The first screw 29 and the second screw 210 are fixed with screw ridge a, the second shearing teeth of the tooth type, screw ridge b and screw ridge c in sequence. Through the combination of the screw ridge and the second shearing teeth and the change of the gap between the screw ridges, the flipping at various angles is achieved, so that the mixing is more complete;

[0053] Compression section b219: The compression section after the mixing section further compacts the material. After mixing, the material may still be relatively loose. The compression section applies pressure to the material through the action of the screw and other components to compact it, making the material denser and expelling the air in the material.

[0054] Exhaust section b220: exhaust the material again;

[0055] Extrusion section 221: conveying and pressurizing the material, establishing a certain pressure, making the material at the die mouth have a certain density, and further mixing, ultimately achieving the purpose of smooth extrusion granulation.

[0056] Further, such as Fig.11 As shown, the first screw 29 and the second screw 210 have the same structure and are both small conical screws. Their diameters gradually decrease along the material conveying direction. The diameter at the end away from the discharge port 212 is D1, and the diameter at the end close to the discharge port 212 is D2. Their length is L, and their cone angle is α, tanα=(D1-D2) / 2 / L, tanα is 0.001~0.009, and their aspect ratio is A, A=L / D2, and A is 30~40.

[0057] Furthermore, for common conical twin screws, the conical screws are generally designed according to the ratio of 2:1 between the large and small head diameters, and the aspect ratio A is adjusted within the range of 20 to 23. Taking the 65 / 132 diameter conical twin screw barrel, which is widely used in the market, as an example, the effective length of the screw is 1420mm, the large head diameter is 132mm, the small head diameter is 65mm, and the aspect ratio is 1420 / 65, which is approximately equal to 22 times, tanα = (132-65) / 2 / 1420 = 0.0236. The first screw 29 and the second screw 210 of the present invention can have a diameter of 145 / 192, a length of 5588 mm, a large head diameter of 192 mm, a small head diameter of 145 mm, and an aspect ratio of 5588 / 145 exceeding 38 times, tanα=(192-145) / 2 / 5588≈0.0042. From the above data, it can be seen that the first screw 29 and the second screw 210 of the present invention are small-taper ultra-long-diameter screws, and their advantages are as follows:

[0058] The first small taper: Compared with parallel twin-screw barrels, the working pressure of the inner cavity of the conical twin-screw barrel is higher, which can significantly improve the working efficiency of the plastic extruder. Ordinary conical twin-screw barrels have a relatively large cone angle, and the screw speed is highly sensitive to the pressure in the barrel cavity. The small taper of the present invention is that the screw speed is relatively less sensitive to the pressure in the barrel cavity, which is more conducive to accurately adjusting the working pressure in the barrel cavity by adjusting the screw speed. The speed adjustment range is relatively larger. According to the performance of the processed raw materials, different extrusion products can be processed by setting different speeds in a targeted manner, and the types of raw materials that can be selected are more diverse. At the same time, since the working pressure in the barrel cavity can be accurately adjusted, it is beneficial to improve the quality of the products processed by the plastic extruder.

[0059] The second extra-long diameter: the working length of the screw in the barrel is extended, the component structure is optimized, and the mixing is more sufficient. Since the screw stroke is lengthened, more blending areas can be arranged. During the processing of PET and calcium powder mixed products, a large amount of air will be mixed. In order to reduce the air content in the product, an exhaust section can be reasonably set in the lengthened barrel. The present invention can exhaust the gas in time by setting two exhaust sections, so that the raw materials are mixed more fully and the extrusion is smoother, because the gas will occupy a certain space and affect the full mixing of the materials.

[0060] Example 3

[0061] like Figure 6-Figure 10 As shown, the difference from the above embodiment is that the auxiliary mechanism 3 also includes a first accommodating slot 31, a plurality of first accommodating slots 31 are opened in the barrel 28, the first accommodating slots 31 are symmetrically distributed on both sides of the exhaust port 211, the first accommodating slots 31 are adjacent to the exhaust port 211, the shape of the first accommodating slot 31 is the same as the shape of the inner wall of the barrel 28, a first annular rail 32 is fixedly installed in the first accommodating slot 31, the shape of the first annular rail 32 is the same as the shape of the first accommodating slot 31, the size of the first annular rail 32 is matched with the size of the first accommodating slot 31, the first annular rail 32 and the barrel 28 are sealed, a moving part 33 is movably installed on the first annular rail 32, the shape of the moving part 33 is the same as the first annular rail 32, the moving part 33 passes through the wall of the first annular rail 32, and the moving part 33 and the first annular rail 32 are sealed.

[0062] Furthermore, a toothed belt 35 is fixedly mounted on the outer ring of the movable member 33. The shape of the toothed belt 35 is the same as that of the movable member 33. The toothed belt 35 passes through the barrel bracket 22. A plurality of auxiliary gears 36 are rotatably mounted on the barrel bracket 22. The auxiliary gears 36 are meshed with the toothed belt 35. A first traction wheel 37 is fixedly mounted on the shaft of the auxiliary gear 36.

[0063] Furthermore, a servo motor 38 is fixedly mounted on the base 1 , and the servo motor 38 is located inside the machine cover 21 . A second traction wheel 39 is fixedly mounted on the shaft of the servo motor 38 , and a belt 310 is tensioned between the second traction wheel 39 and the first traction wheel 37 .

[0064] Furthermore, a second accommodating slot 311 is provided in the barrel 28, and the shape of the second accommodating slot 311 is the same as the shape of the inner wall of the barrel 28. A second annular rail 312 is fixedly installed on the second accommodating slot 311, and the shape of the second annular rail 312 is the same as the shape of the second accommodating slot 311. A protective collar 313 is movably installed on the inner ring of the second annular rail 312, and the shape of the protective collar 313 is the same as the second annular rail 312. A plurality of ball rods 314 are provided between the protective collar 313 and the second annular rail 312, and the ball rods 314 are evenly distributed between the protective collar 313 and the second annular rail 312.

[0065] When the auxiliary material is exhausted, the servo motor 38 is started, the servo motor 38 drives the second traction wheel 39 to rotate, the second traction wheel 39 drives the belt 310 to rotate, the belt 310 drives the first traction wheel 37 to rotate, the first traction wheel 37 drives the auxiliary gear 36 to rotate, the auxiliary gear 36 drives the toothed belt 35 to move, the toothed belt 35 drives the moving member 33 to move on the first annular rail 32, the moving member 33 drives the lever 34 to move, so that the lever 34 stirs the material; at the same time, as the first screw 29 and the second screw 210 rotate, when the first screw 29 or the second screw 210 contacts the protective collar 313, the first screw 29 or the second screw 210 drives the protective collar 313 to move on the second annular rail 312, so that the first screw 29 and the second screw 210 will not generate a lot of friction with the inner wall of the barrel 28, and the ball rod 314 reduces the friction between the protective collar 313 and the second annular rail 312.

[0066] Furthermore, according to production needs, the setting length of some extruders may span the entire production workshop. A large number of bubbles may accumulate inside the longer barrel 28, causing the internal air pressure of the barrel 28 to be relatively high. Therefore, additional settings of the auxiliary mechanism 3 are required on larger extruders.

[0067] Specifically, an extension cavity is provided on the barrel 28, and the extension cavity of the barrel 28 is an integral structure with the barrel 28, that is, it is a rigid part cast as an integral part by using a mold. The auxiliary gear 36, the first traction wheel 37, the servo motor 38, the second traction wheel 39, and the belt 310 in the auxiliary mechanism 3 are all arranged in the extension cavity of the barrel 28. The first annular rail 32 and the moving part 33 separate the interior of the barrel 28 from the extension cavity of the barrel 28, so that the auxiliary mechanism 3 is arranged as a whole inside the structure of the barrel 28, thereby preventing the high air pressure in the barrel 28 from causing the barrel 28 to explode.

[0068] Furthermore, due to the pressure difference between the interior of the barrel 28 and the extension chamber of the barrel 28, a plurality of triangular stabilizing frames made of rigid materials are arranged in the extension chamber of the barrel 28, and the triangular stabilizing frames are evenly distributed beside the first annular rail 32. Rotating wheels are arranged on the triangular stabilizing frames, and the rotating wheels are in contact with the moving part 33, so that the rotating wheels can assist in supporting the moving part 33 made of soft materials. At the same time, a pressure detector is arranged on a single rotating wheel, and the detection end of the pressure detector is in contact with the moving part 33. A high-pressure gas tank and an air pump are arranged in the extension chamber of the barrel 28. When the pressure detector detects that the moving part 33 begins to deform under pressure, the air pump will synchronously release gas to balance the pressure difference between the interior of the barrel 28 and the extension chamber of the barrel 28, thereby maintaining the pressure balance between the interior of the barrel 28 and the extension chamber of the barrel 28.

[0069] Furthermore, the extension cavity of barrel 28 is under pressure to maintain the overall structural integrity of barrel 28, and the pressure balance method between the inside of barrel 28 and the extension cavity of barrel 28 are both existing technologies, which need to be selectively set according to the size of the extruder equipment. In addition, the setting of the extension cavity of barrel 28 has no substantial impact on the improvement of the present invention, so it will not be repeated here.

[0070] The overall working principle of the extruder:

[0071] First, the material is fed into one end of the barrel 28, and the material is transported forward from the inside of the barrel 28, and the heater 24 is started. The heater 24 heats the inside of the barrel 28, so that the material melts inside the barrel 28, and then the molten material is extruded from the other end of the barrel 28. At the same time, the moving member 33 is driven to move, so that the moving member 33 moves in an "8"-shaped trajectory inside the barrel 28, and the moving member 33 drives the lever 34 to move, so that the lever 34 turns the material in the barrel 28, thereby assisting the material to turn over in the exhaust area to help the bubbles in the material escape, thereby forming a stirring action for the molten material in the barrel, and the molten material is turned over at the exhaust port to assist the molten material to exhaust, thereby improving the exhaust efficiency within a specific exhaust time period, reducing the bubble content in the molten material, avoiding the bubbles from affecting the extrusion molding of the material, and improving the production quality of the extruder;

[0072] When the auxiliary material is exhausted, the servo motor 38 is started, the servo motor 38 drives the second traction wheel 39 to rotate, the second traction wheel 39 drives the belt 310 to rotate, the belt 310 drives the first traction wheel 37 to rotate, the first traction wheel 37 drives the auxiliary gear 36 to rotate, the auxiliary gear 36 drives the toothed belt 35 to move, the toothed belt 35 drives the moving member 33 to move on the first annular rail 32, the moving member 33 drives the lever 34 to move, so that the lever 34 stirs the material; at the same time, as the first screw 29 and the second screw 210 rotate, when the first screw 29 or the second screw 210 contacts the protective collar 313, the first screw 29 or the second screw 210 drives the protective collar 313 to move on the second annular rail 312, so that the first screw 29 and the second screw 210 will not generate a lot of friction with the inner wall of the barrel 28, and the ball rod 314 reduces the friction between the protective collar 313 and the second annular rail 312.

[0073] Although 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 appended claims and their equivalents.

Claims

1. An ultra-long small-taper twin-barrel screw extruder for plastic recycling, comprising a base (1), an extrusion mechanism (2) arranged on the base (1), and an auxiliary mechanism (3) arranged on the extrusion mechanism (2), characterized in that: The extrusion mechanism (2) comprises a heater (24) and a barrel (28); the heater (24) is fixedly mounted on the base (1); the heater (24) is used to perform a melting process on the material; the barrel (28) is arranged on the base (1); the barrel (28) passes through a heating area of ​​the heater (24); and the barrel (28) is used to perform a conveying process on the material; The auxiliary mechanism (3) comprises a moving part (33) and a lever (34). The moving part (33) is movably arranged in the barrel (28). The moving part (33) is located in the exhaust area of ​​the extruder. The shape of the moving part (33) is matched with the shape of the inner wall of the barrel (28). A plurality of levers (34) are fixedly mounted on the inner ring wall surface of the moving part (33). The levers (34) are evenly distributed on the moving part (33). The length of the lever (34) is matched with the length of the exhaust area of ​​the extruder. The lever (34) moves synchronously with the moving part (33).

2. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 1, characterized in that: The extrusion mechanism (2) also includes a machine cover plate (21), the machine cover plate (21) is fixedly mounted on the base (1), a barrel bracket (22) is arranged inside the machine cover plate (21), the barrel bracket (22) is fixedly mounted on the base (1), the barrel bracket (22) passes through both ends of the machine cover plate (21), a feed hopper (23) is fixedly mounted on the machine cover plate (21), the bottom end of the feed hopper (23) passes through the wall surface of the machine cover plate (21), the bottom end of the feed hopper (23) passes through the barrel bracket (22), the bottom end of the feed hopper (23) is connected to the barrel (28), and the barrel (28) passes through the heating area of ​​the heater (24).

3. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 2, characterized in that: A main motor (25) is fixedly mounted on the base (1), a coupling (26) is fixedly mounted on the shaft of the main motor (25), a gear set (27) is arranged on the base (1), one end of the gear set (27) is connected to the coupling (26) by power, the other end of the gear set (27) extends into the barrel (28), a first screw (29) is arranged in the barrel (28), a second screw (210) is arranged in the barrel (28), the first screw (29) and the second screw (210) are thread-matched, the gear set (27) is connected to the first screw (29) by power, and the gear set (27) is connected to the second screw (210) by power, so that the first screw (29) and the second screw (210) rotate relative to each other.

4. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 3, characterized in that: The barrel (28) is provided with a plurality of exhaust ports (211), the exhaust ports (211) are located in the exhaust area of ​​the extruder, the exhaust ports (211) are communicated with the interior of the machine cover plate (21), a discharge port (212) is fixedly installed at one end of the barrel (28), the discharge port (212) is communicated with the barrel (28), the discharge port (212) passes through the barrel bracket (22), and the discharge port (212) passes through the machine cover plate (21).

5. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 4, characterized in that: The barrel (28) includes a plurality of regions therein. A feeding section (213) is provided at one end of the barrel (28). The feeding section (213) is used to transport materials. A pre-plasticizing section (214) is provided inside the barrel (28). The pre-plasticizing section (214) is adjacent to the feeding section (213). The pre-plasticizing section (214) is used to heat and soften the materials. A mixing section a (215) is provided inside the barrel (28). The mixing section a (215) is adjacent to the pre-plasticizing section (214). The mixing section a (215) is used to mix and shear the materials. The barrel (28) is provided with a compression section a (216) inside, the compression section a (216) is adjacent to the mixing section a (215), the compression section a (216) is used to compact the material, the barrel (28) is provided with an exhaust section a (217) inside, the exhaust section a (217) is adjacent to the compression section a (216), the exhaust section a (217) is used to exhaust the material, the barrel (28) is provided with a mixing section b (218) inside, the mixing section b (218) is adjacent to the exhaust section a (217), the mixing section b (218) is used to again The material is mixed and sheared, a compression section b (219) is provided inside the barrel (28), the compression section b (219) is adjacent to the mixing section b (218), the compression section b (219) is used to compact the material again, a venting section b (220) is provided inside the barrel (28), the venting section b (220) is adjacent to the compression section b (219), the venting section b (220) is used to vent the material again, an extrusion section (221) is provided inside the barrel (28), the extrusion section (221) is adjacent to the venting section b (220), the extrusion section The section (221) is used for extruding materials. The first screw (29) and the second screw (210) are both fixed with a plurality of first shearing teeth with a tooth shape at the mixing section a (215). The first shearing teeth on the first screw (29) and the second screw (210) are meshed with each other. The first screw (29) and the second screw (210) are both fixed with screw ridge a, second shearing teeth with a tooth shape, screw ridge b and screw ridge c in sequence at the mixing section b (218). The second shearing teeth on the first screw (29) and the second screw (210) are meshed with each other.

6. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 5, characterized in that: The first screw (29) and the second screw (210) have the same structure and are both small conical screws, whose diameters gradually decrease along the material conveying direction, whose diameters at the end away from the discharge port (212) are D1, and whose diameters at the end close to the discharge port (212) are D2. Their lengths are L, and their taper angles are α, tanα=(D1-D2) / 2 / L, tanα is 0.001-0.009, and their aspect ratios are A, A=L / D2, and A is 30-40.

7. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 6, characterized in that: The auxiliary mechanism (3) further comprises a first accommodating notch (31), a plurality of the first accommodating notches (31) are provided in the barrel (28), the first accommodating notches (31) are symmetrically distributed on both sides of the exhaust port (211), the first accommodating notches (31) are adjacent to the exhaust port (211), the shape of the first accommodating notch (31) is the same as the shape of the inner wall surface of the barrel (28), a first annular rail (32) is fixedly installed in the first accommodating notch (31), and the shape of the first annular rail (32) is The first annular rail (32) has the same shape as the first accommodating groove (31), the size of the first annular rail (32) is matched with the size of the first accommodating groove (31), the first annular rail (32) and the barrel (28) are sealed, the moving part (33) is movably mounted on the first annular rail (32), the shape of the moving part (33) is the same as the first annular rail (32), the moving part (33) passes through the wall of the first annular rail (32), and the moving part (33) and the first annular rail (32) are sealed.

8. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 7, characterized in that: A toothed belt (35) is fixedly mounted on the outer ring of the moving member (33). The shape of the toothed belt (35) is the same as that of the moving member (33). The toothed belt (35) passes through the barrel bracket (22). The barrel bracket (22) is rotatably matched with a plurality of auxiliary gears (36). The auxiliary gears (36) are meshed with the toothed belt (35). A first traction wheel (37) is fixedly mounted on the shaft of the auxiliary gear (36).

9. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 8, characterized in that: A servo motor (38) is fixedly mounted on the base (1), the servo motor (38) is located inside the machine cover plate (21), a second traction wheel (39) is fixedly mounted on the shaft of the servo motor (38), and a belt (310) is tensioned between the second traction wheel (39) and the first traction wheel (37).

10. The ultra-long small-taper twin-barrel screw extruder for plastic recycling according to claim 9, characterized in that: A second accommodating notch (311) is provided in the barrel (28), and the shape of the second accommodating notch (311) is the same as the shape of the inner wall of the barrel (28); a second annular rail (312) is fixedly installed on the second accommodating notch (311), and the shape of the second annular rail (312) is the same as the shape of the second accommodating notch (311); a protective collar (313) is movably installed on the inner ring of the second annular rail (312), and the shape of the protective collar (313) is the same as the shape of the second annular rail (312); a plurality of ball rods (314) are provided between the protective collar (313) and the second annular rail (312), and the ball rods (314) are evenly distributed between the protective collar (313) and the second annular rail (312).

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