Extrusion molding device for ultra-high molecular weight polyethylene pipe production

Abstract

The invention relates to the technical field of extrusion molding, in particular to an extrusion molding device for ultra-high molecular weight polyethylene pipe production, which comprises an extrusion cylinder, double screws and heating rings, the heating rings are uniformly distributed on the outer wall of the extrusion cylinder, the double screws are rotatably mounted in the extrusion cylinder, and a motor connected with the double screws is further arranged at the tail end of the extrusion cylinder. By arranging the driving assembly and the scraping assembly, when waste attached to the double screws is increased and the pressure in the extrusion barrel is increased, the driving assembly moves due to the increase of the pressure, a gear on the driving assembly transmits power of a motor to a lead screw, and the lead screw rotates to drive the scraping assembly to move back and forth while the scraping assembly is driven to move back and forth. According to the double-screw extruder, the scraper on the double-screw extruder extends out of the scraping assembly, then waste adhered to the double screws is scraped, after the waste is scraped, the pressure in the extrusion cylinder is reduced, the plug rod is reset, the scraper retracts into the scraping assembly, and then it is guaranteed that the scraper does not interfere with follow-up materials.

Description

Technical Field

[0001] The invention relates to the technical field of extrusion molding, in particular to an extrusion molding device for producing ultra-high molecular weight polyethylene pipes. Background Art

[0002] Ultra-high molecular weight polyethylene is a high-strength and lightweight material with high tensile strength and impact resistance. It can maintain its structural integrity under extreme conditions. It has a wide range of applications: it can be used in transportation systems, medical equipment, sports equipment and other fields. Existing extrusion devices for pipe production usually use screw extruders for production. When the existing extruder extrudes ultra-high molecular weight polyethylene materials, compared with ordinary polyethylene, due to the characteristics of ultra-high molecular weight polyethylene itself, it is not easy to flip and stir during the transportation process, which will cause a large heat difference between the upper and lower parts. Therefore, the screw is prone to cooling and solidification problems. Ultra-high molecular weight polyethylene has strong adhesion, and pipes made of ultra-high molecular weight polyethylene have poor melt fluidity due to its high molecular weight, which may cause uneven heating during pipe molding and extrusion. Therefore, when flowing in the extrusion barrel, it is easy to adhere to the outer wall of the screw due to the temperature difference. For a long time, a large amount of material will adhere to the outer wall of the screw and interfere with the subsequent material flow, and even the extrusion barrel will be completely blocked.

[0003] In response to the above problems, the prior art provides some solutions, such as regularly arranging personnel to remove the screw in the extruder and clean the inner wall of the extrusion barrel and the screw at the same time. Due to the characteristics of ultra-high molecular weight polyethylene itself, the extruder needs to be cleaned after a short period of use. Although a relatively good cleaning effect can be achieved through manual and machine cleaning at the same time, it increases the workload of personnel and reduces the continuity of generation. For example, the invention patent with patent application number CN202122626291.3 provides an extruder that prevents material adhesion. A high-pressure cleaning device is set up to accelerate the outflow of materials from the top of the discharge pipe downward, and the inner wall of the discharge pipe is removed synchronously at the same time. The side wall separation device can reduce the degree of connection between the material and the side wall of the discharge pipe to prevent the material from adhering to the side wall and affecting the material. Normal outflow is disturbed, thereby avoiding pipeline blockage, keeping the discharge pipeline within a stable temperature range, thereby slowing down the cooling and solidification speed of the material, keeping it fully fluid, and preventing the material from adhering to the discharge pipeline. The faster wind flow is used to speed up the internal material flow, and the air outlet ports are located on both sides of the discharge pipeline to guide the wind to the inner wall of the discharge pipeline so that the material can be detached from the discharge pipeline, further reducing the amount of material adhering to the pipeline. However, the faster wind flow in this scheme will increase the cooling and solidification speed of the material, and its fluidity will decrease after the material temperature drops. The material temperature at the screw is the lowest, which makes it easy for the material to adhere to the screw. The adhering material will increase the resistance of the screw, resulting in poor material flow during the processing, thereby reducing production efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide an extrusion device for the production of ultra-high molecular weight polyethylene pipes, so as to solve the problem that the ultra-high molecular weight polyethylene itself is not easy to be turned over and stirred during the transportation process, which will cause a large heat difference between the upper and lower parts of the extrusion barrel. Therefore, when flowing in the extrusion barrel, it is easy to adhere to the outer wall of the screw due to the temperature difference. If this continues for a long time, a large amount of material will adhere to the outer wall of the screw and interfere with the subsequent flow of materials. When the above problem occurs in the extrusion device, the quality of the extruded material is reduced, and at the same time, the shortcomings of the existing technical solutions are solved.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An extrusion device for producing ultra-high molecular weight polyethylene pipes comprises an extrusion barrel, a twin screw and a heating ring, wherein the heating ring is evenly distributed on the outer wall of the extrusion barrel, the twin screw is rotatably installed in the extrusion barrel, and a motor connected to the twin screw is also provided at the tail end of the extrusion barrel. Specifically, a mounting hole and a through hole are formed through the inner wall of the extrusion barrel, and the through hole and the mounting hole are located directly above the motor. A screw is installed in the through hole, a belt group is provided on the screw, a driving component is provided in the mounting hole, a gear is also provided on the driving component, and the gear is connected to the output end of the motor. The driving component controls the connection between the tooth surface of the gear and the belt group through the change of the pressure in the extrusion barrel, and transmits the power of the motor to the screw through friction. A plurality of sliders and cams are also provided on the screw, a scraping component is provided in the slider, and a scraper is provided in the scraping component, and the scraper of the scraping component moves to the twin screw when the cam rotates.

[0007] It is easy to understand that due to the characteristics of the material of ultra-high molecular weight polyethylene itself, the fluidity of the molten material is poor. Therefore, it is not easy to flip and stir during the transportation process, which will cause a large heat difference between the upper and lower parts. In addition, the ultra-high molecular weight polyethylene has strong adhesion, so it is easy to adhere to the outer wall of the screw due to the temperature difference when flowing in the extruder barrel. Because the waste adhered to the twin screws increases, the gap between the extruder barrel and the twin screws decreases, causing the pressure in the extruder barrel to rise, thereby causing the drive assembly to move toward the outside of the extruder barrel, and the gear on it is connected to the motor while moving toward the belt group until the tooth surface fits the belt group. The motor transmits power to the screw through the magnetic connection of the gear and the belt group. Because the rotation of the screw drives the scraping assembly to reciprocate while the cam rotates, the scraper on it extends from the scraping assembly, thereby achieving the purpose of scraping off the waste adhered to the twin screws. When the waste is scraped off, the pressure in the extruder barrel decreases, and the plug rod is reset to reduce the torque of the gear and belt group, thereby cutting off the power. The scraper retracts into the scraping assembly because the cam stops, thereby ensuring that the scraper does not interfere with subsequent materials.

[0008] Preferably, the drive assembly also includes a plug rod, a return spring and a transmission part, the plug rod is slidably installed in the mounting hole, the upper and lower ends of the plug rod are respectively connected to the inner wall of the extrusion barrel and the transmission part, the upper and lower ends of the return spring are respectively connected to the transmission part and the mounting hole, and the transmission part is located in the mounting hole and connected to the gear.

[0009] It is easy to understand that the drive assembly reaches the reset spring deformation value through the pressure in the extruder barrel, thereby moving the gear, and achieving adhesion with the belt group through magnetic force, thereby generating sufficient torque to drive the screw to rotate. The measurement accuracy of the plug rod is not affected by external environmental factors such as electromagnetic interference and temperature fluctuations. If an electronic pressure gauge is used, it is easy to be affected by factors such as electromagnetic fields, temperature changes, and humidity, resulting in measurement errors or signal instability, especially in the high-temperature environment of the extruder barrel. Measuring the change in pressure through the movement of the plug rod can better ensure the accuracy of the timing of scraper extension, thereby reducing the setting of external power, and the structure is simple, which can effectively reduce the manufacturing cost of the extrusion device. The meshing setting of the gear and the output end of the motor can increase the rotation speed of the screw by setting the gear transmission ratio, thereby ensuring that the scraping assembly can scrape the outer wall of the twin screw along with the threads on the twin screw.

[0010] Preferably, the screw rod is also provided with a reciprocating thread and a rotating tooth, the reciprocating thread is located outside the extrusion barrel and rotates with the belt group, a plurality of the sliders are arranged in an array on the rotating tooth, the slider is provided with an arc surface, a movable plate and an inner plate, the arc surface fits the extrusion barrel, the movable plate is installed at the lower end of the slider, the inner plate is installed in the extrusion barrel and the movable plate is slidably connected, a scraping groove is also provided on the inner plate, and the scraping groove is slidably connected to the slider.

[0011] It is easy to understand that since the belt group rotates the screw rod in one direction, a reciprocating thread is provided at the connection between the screw rod and the belt group, and the reciprocating thread is the reciprocating distance of the slider. A plurality of sliders are arranged in an array on the rotating teeth to realize the reciprocating movement of the slider, and fit with the extruder barrel through the arc surface, so that the scraper extension direction of the slider is always above the twin screw during the movement, thereby ensuring that the scraper is always located on the intersection line of the twin screw threads while moving on the outer surface of the twin screw. By providing a reciprocating thread on the screw rod, the problem of requiring more parts for other transmission structures is avoided, and the complexity of the transmission structure and the difficulty of maintenance are reduced; at the same time, in order to avoid the excessive space in the extruder barrel due to the setting of the screw rod and the scraping assembly, so that the material is away from the twin screw, a moving plate is installed between the plurality of sliders, and the moving plate slides in contact with the upper end surface of the inner plate while the screw rod moves, and the scraper extends from the scraping groove, which ensures that the space in the extruder barrel is compact and its sealing is also guaranteed, because the fit of the moving plate and the inner plate prevents the material from entering the slider.

[0012] Preferably, the scraper assembly further comprises a mounting groove, a sliding block and a scraper spring, the mounting groove is arranged in the sliding block and the opening of the mounting groove is located on the vertical projection plane of the twin screw, the sliding block is slidably mounted in the mounting groove, the upper and lower ends of the scraper spring are respectively connected to the mounting groove and the sliding block, the scraper is connected to the sliding block, a slideway is further arranged on the inner wall of the mounting groove, the cam is installed in the slideway, a piston, a crank and cam teeth are further arranged on the cam, the upper and lower ends of the crank are respectively rotatably connected to the piston and the cam, The cam teeth are meshed with the rotating teeth and are fixedly connected to the cam, the outer edge surface of the piston is slidably connected to the mounting groove, and a movable groove is also provided above the mounting hole, a locking spring and a sealing block are installed in the movable groove, the front and rear ends of the locking spring are respectively connected to the inner wall of the movable groove and the rear side of the sealing block, a locking shaft is also slidably connected in the movable plate, the inner wall of the extrusion cylinder is connected to the locking shaft through a second locking spring, the locking shaft abuts against the sealing block, a second through hole is provided on the sliding block, and the locking shaft passes through the second through hole.

[0013] It is easy to understand that when the pressure in the extruder increases to the rated value, that is, when the screw rotates, the cam teeth meshing with it rotate synchronously, and the cam connected to the cam teeth rotates in the slideway accordingly, and the crank is connected to the piston. As the cam rotates, the three form a crank-connecting rod mechanism. As the piston reciprocates up and down in the slideway, the sliding block is pushed by the piston and moves toward the outside of the mounting groove opening, thereby causing the scraper to extend out of the mounting groove. Since the sliding block and the mounting groove are interference fit, the pulling force of the scraping spring has a slow reset speed for the sliding block. Due to the continuous up and down movement of the piston, after the initial pressing of the sliding block, the moving plate is subjected to pressure to resist the elastic force of the locking spring and moves into the movable groove. The reciprocating distance of the moving plate in the movable groove is equal to the length of the reciprocating thread, and the locking shaft is The pulling force of the second locking spring abuts against the sealing block. During the displacement of the locking shaft, the sliding block completely extends out of the mounting groove. The locking shaft is displaced due to the change in pressure and then completely penetrates the second through hole on the sliding block. Since the reaction force exerted by the twin screw on the scraper can only be transmitted upward along the mounting groove, and the displacement direction of the locking shaft is 90° to the direction of the reaction force, the sliding block will not be unlocked due to the reaction force after being locked. When the pressure in the extruder barrel is higher than the set value, the scraper is always on the intersection line of the twin screws due to the cooperation between the second through hole and the locking shaft. When the pressure in the extruder barrel is lower than the set value, the scraper and the sliding block are both retracted into the mounting groove, thereby avoiding the obstruction of material transportation by multiple scrapers, thereby ensuring the stability of the scraper when scraping the twin screws.

[0014] Preferably, the movable groove is connected to the mounting hole, and a locking pin is slidably connected in the movable groove. Inclined surfaces are provided on the upper and lower ends of the locking pin shaft and the rear end surface of the sealing block. The upper and lower inclined surfaces of the locking pin respectively abut the inclined surfaces on the rear end surface of the sealing block and the plug rod.

[0015] It is easy to understand that in order to avoid the pressure fluctuation in the extruder barrel caused by the gradual reduction of waste on the double threads during the scraper scraping the double threads, the reset spring is not deformed enough, and the plug rod moves back and forth in the mounting hole, resulting in insufficient torque between the gear and the belt group. When the plug rod moves into the mounting hole, the locking pin shaft abuts against the outer edge of the plug rod, and the locking pin cannot fall. The upper end of the locking pin abuts against the rear end of the sealing block. When the displacement distance of the plug rod is at the pressure setting value, the locking pin completely falls and abuts against the plug rod head, thereby limiting the displacement of the plug rod, thereby ensuring the gear and belt group. Due to the coupling of the belt group, the locking pin no longer abuts against the sealing block, and the sealing block moves into the movable groove due to the pressure and the thrust of the locking shaft on the second locking spring, thereby ensuring that the locking shaft locks the scraper only after it is fully extended out of the mounting groove, thereby avoiding the hard friction between the locking shaft and the outer wall of the sliding block causing bending deformation and wear of the sliding block. When the pressure drops completely, the sealing block and the plug rod cooperate with the inclined surface to release the lock of the plug rod, thereby ensuring the accuracy of the scraper extension position and the sealing of the sliding block and the mounting groove, thereby ensuring the effect of the scraper on cleaning the outer surface of the twin screw.

[0016] Preferably, an adjusting screw, an adjusting spring and an adjusting disk are also provided on one side of the transmission part. The adjusting disk is arranged in the mounting hole and is threadedly connected to the adjusting screw. The adjusting spring is sleeved on the adjusting screw and its two ends are respectively in contact with the transmission part and the inner wall of the mounting hole.

[0017] It is easy to understand that by manually turning the adjusting screw, the plug rod can be flexibly controlled to be at different rated pressures, which will cause the gear to transmit the power of the motor to the screw rod, thereby avoiding slight changes in the pressure in the extruder barrel, so that the scraper component is started when the pressure does not meet the rated pressure, causing interference with the heating and melting of the material, thereby improving the stability and accuracy of the drive component.

[0018] Preferably, a guide groove is further provided at the open end of the mounting groove, the guide groove is in contact with the outer wall of the sliding block, and the guide groove is in an inner arc shape away from the direction of the sliding block.

[0019] It is easy to understand that in order to prevent the sliding block and the scraper from having too much material adhered to the outer wall after scraping the waste on the twin screws, causing the waste to solidify in the mounting groove, an inner arc guide groove is provided at the open end of the mounting groove, which is away from the direction of the sliding block. When the scraper is reset due to the pulling force of the scraping spring, the material on the sliding block and the scraper is easier to enter the guide groove relative to the gap between the sliding block and the mounting groove, and the material is guided away from the mounting groove by the setting of the inner arc. Because of the pulling force of the scraping spring, the material obtains initial power when it is squeezed out of the guide groove, thereby preventing the material from being trapped in the guide groove, thereby ensuring the cleaning effect of the scraper in scraping the twin screws.

[0020] Preferably, a tympanic membrane and a sealing ring are further provided on the inner wall of the mounting hole facing the extrusion barrel, and the two ends of the tympanic membrane are respectively abutted against the sealing ring and the plug rod, and the tympanic membrane includes a fixing part and a deformation part, and the fixing part and the sealing ring are both fixed in the mounting hole, and the deformation part is abutted against the plug rod and isolates the polyethylene in the extrusion barrel.

[0021] It is easy to understand that by arranging a sealing ring and a tympanic membrane in the mounting hole, the tympanic membrane will deform into the mounting hole when under pressure, and by arranging a sealing ring, the sliding stroke of the plug rod is guaranteed when under pressure, and after long-term use, the sensitivity of the drive component will not be affected by wear due to friction with the inner wall of the mounting hole, thereby ensuring that the cleaning effect of the twin screw is still guaranteed after the extrusion device is used for a long time.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention sets a driving assembly and a scraping assembly. As the amount of waste adhered to the twin screws increases, the gap between the extruder barrel and the twin screws decreases, causing the pressure in the extruder barrel to rise, thereby causing the driving assembly to move. The gear on the driving assembly transmits the power of the motor to the screw. As the screw rotates, the scraping assembly is driven to reciprocate, and the scraper on the scraping assembly extends from the scraping assembly, thereby achieving the purpose of scraping off the waste adhered to the twin screws. After the waste is scraped off, the pressure in the extruder barrel decreases, the plug rod contracts to cut off the power, and the scraper retracts into the scraping assembly, thereby ensuring that the scraper does not interfere with subsequent materials.

[0024] 2. The present invention provides a movable plate and an inner plate, and installs the movable plate between a plurality of sliders. When the screw moves, the movable plate slides in close contact with the upper end surface of the inner plate, and the scraper extends from the scraping groove. The scraping assembly and the screw avoid direct contact with the material. While ensuring the compactness of the space in the extruder barrel, the sealing is also ensured because the close contact between the movable plate and the inner plate prevents the material from entering the slider, thereby ensuring the normal transportation of the material by the twin screw.

[0025] 3. The present invention sets a locking pin to realize the interval of the movement timing of the plug rod and the sealing block. The sealing block moves into the movable groove due to the pressure and the thrust of the second locking spring on the locking shaft, thereby ensuring that the locking shaft locks the scraper only after it is fully extended out of the mounting groove, thereby avoiding the hard friction between the locking shaft and the outer wall of the sliding block causing bending deformation and wear of the sliding block, thereby ensuring the accuracy of the scraper extension position and the sealing of the sliding block and the mounting groove, and further ensuring the effect of the scraper on cleaning the outer surface of the twin-screw.

[0026] 4. The present invention provides a semicircular guide groove, and opens an inner arc guide groove at the open end of the mounting groove in a direction away from the sliding block. When the scraper is reset due to the pulling force of the scraping spring, the sliding block and the material on the scraper are relative to the gap between the sliding block and the mounting groove, and the material is more likely to enter the guide groove. The material is guided away from the mounting groove by the setting of the inner arc. Because of the pulling force of the scraping spring, the material obtains initial power when it is squeezed out of the guide groove, thereby avoiding the material from being retained in the guide groove, thereby ensuring the scraper's double-screw cleaning effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic structural diagram of an extrusion device for producing ultra-high molecular weight polyethylene pipes of the present invention;

[0028] Figure 2 for Figure 1 Full cross-section at AA in the middle;

[0029] Figure 3 for Figure 1 A magnified view of the structure of the drive assembly at B in the middle, in coordination with the motor and the belt assembly;

[0030] Figure 4 A half-section diagram of the rotating structure of the driving component and the scraping component;

[0031] Figure 5 for Figure 4 A magnified view of the two-dimensional structural state at C in the middle;

[0032] Figure 6 It is a full cross-sectional view of the structure in which the scraper extends from the mounting groove and is locked by the locking shaft;

[0033] Figure 7 This is a schematic diagram of the structural state of the scraper retracting into the installation groove when the screw rod is stationary;

[0034] Figure 8 This is the parts drawing of the locking shaft.

[0035] In the figure: 1. extruder; 1011. mounting hole; 1012. through hole; 102. twin screw; 103. heating ring; 104. motor; 1041. output tooth; 105. screw rod; 1051. belt group; 1052. reciprocating thread; 1053. rotating tooth; 106. slider; 1061. arc surface; 1062. moving plate; 1063. inner plate; 1064. scraper groove; 107. cam; 1071. piston; 1072. crank; 1073. cam tooth; 2. drive assembly; 201. gear; 202. plug rod; 203. reset Spring; 204, transmission part; 2041, adjusting screw; 2042, adjusting spring; 2043, adjusting disk; 3, scraping assembly; 301, mounting groove; 3011, slideway; 3012, guide groove; 302, sliding block; 3021, second through hole; 3026, scraper; 303, scraping spring; 4, eardrum; 401, fixing part; 402, deformation part; 403, sealing ring; 5, movable groove; 501, locking spring; 502, sealing block; 503, locking shaft; 5031, second locking spring; 504, locking pin; 505, inclined plane. DETAILED DESCRIPTION

[0036] The present invention provides an extrusion device for producing ultra-high molecular weight polyethylene pipes, and the technical scheme is as follows:

[0037] See also Figures 1 to 8 An extrusion device for producing ultra-high molecular weight polyethylene pipes includes an extrusion barrel 1, a twin screw 102 and a heating ring 103, wherein the heating ring 103 is evenly distributed on the outer wall of the extrusion barrel 1, the twin screw 102 is rotatably installed in the extrusion barrel 1, and a motor 104 connected to the twin screw 102 is also provided at the tail end of the extrusion barrel 1. Specifically, a mounting hole 1011 and a through hole 1012 are provided through the inner wall of the extrusion barrel 1, and the through hole 1012 and the mounting hole 1011 are located directly above the motor 104. A screw 105 is installed in the through hole 1012, and a belt group 1051 is provided on the screw 105. The belt group 1051 includes a driving wheel, a belt and a driven wheel, and the driven wheel is rotatably connected to the screw 105, and the driving wheel is connected to the driven wheel through a belt. A driving assembly 2 is provided in the mounting hole 1011, and a gear 201 is also provided on the driving assembly 2. Rotors made of magnetic material are provided on the driving wheel and the gear 201, and a coupling connection is formed between the rotors. The gear 201 is meshed with the output tooth 1041 of the motor 104. The driving assembly 2 controls the gear 201 to approach the driving wheel by the change of the pressure in the extruder barrel 1. As the two get closer, their torque increases, thereby realizing the transmission of the power of the motor 104 to the screw rod 105 through magnetic force. A plurality of sliders 106 and cams 107 are also provided on the screw rod 105. A scraping assembly 3 is provided in the slider 106, and a scraper 3026 is also provided in the scraping assembly 3. When the cam 107 rotates, the scraper 3026 of the scraping assembly 3 moves to the twin screw 102.

[0038] See also Figures 1 to 4 The driving assembly 2 also includes a plug rod 202, a return spring 203 and a transmission part 204. The plug rod 202 is slidably installed in the mounting hole 1011. The upper and lower ends of the plug rod 202 are respectively connected to the inner wall of the extrusion cylinder 1 and the transmission part 204. The transmission part 204 and the mounting hole 1011 are respectively connected to the upper and lower ends of the return spring 203. The transmission part 204 is located in the mounting hole 1011 and is connected to the gear 201. An adjusting screw 2041, an adjusting spring 2042 and an adjusting disk 2043 are also provided on one side of the transmission part 204. The adjusting disk 2043 is arranged in the mounting hole 1011 and is threadedly connected to the adjusting screw 2041. The adjusting spring 2042 is sleeved on the adjusting screw 2041 and its two ends are respectively abutted against the transmission part 204 and the inner wall of the mounting hole 1011. The mounting hole 1011 is also provided with a tympanic membrane 4 and a sealing ring 403 at the inner wall of the extrusion cylinder 1. The two ends of the tympanic membrane 4 are respectively abutted against the sealing ring 403 and The plug rod 202 abuts, the eardrum 4 includes a fixed portion 401 and a deformable portion 402, the fixed portion 401 and the sealing ring 403 are both fixed in the mounting hole 1011, the deformable portion 402 abuts against the plug rod 202 and isolates the material in the extrusion barrel 1, and the screw rod 105 is also provided with a reciprocating thread 1052 and a rotating tooth 1053, the reciprocating thread 1052 is located outside the extrusion barrel 1 and rotates with the belt group 1051, and the rotating tooth 1053 is located inside the extrusion barrel 1, A plurality of sliders 106 are arranged in an array on the rotating gear 1053. The slider 106 is provided with an arc surface 1061, a movable plate 1062 and an inner plate 1063. The arc surface 1061 fits the extrusion tube 1. The movable plate 1062 is installed at the lower end of the slider 106. The inner plate 1063 is installed in the extrusion tube 1 and the movable plate 1062 is slidably connected. A scraping groove 1064 is also provided on the inner plate 1063, and the scraping groove 1064 is slidably connected to the slider 106.

[0039] See also Figures 4 to 8The scraping assembly 3 also includes a mounting groove 301, a sliding block 302 and a scraping spring 303. The sliding block 106 is provided with a mounting groove 301 and the opening of the mounting groove 301 is located on the vertical projection surface of the twin screw 102. The sliding block 302 is slidably installed in the mounting groove 301. The upper and lower ends of the scraping spring 303 are respectively connected to the mounting groove 301 and the sliding block 302. The sliding block 302 is connected to a scraper 3026. The inner wall of the mounting groove 301 is also provided with a slideway 3011. The cam 107 is installed in the channel 3011, and the cam 107 is also provided with a piston 1071, a crank 1072 and a cam tooth 1073. The piston 1071 and the cam 107 are rotatably connected with the upper and lower ends of the crank 1072 respectively. The cam tooth 1073 is engaged with the rotating tooth 1053 and is fixedly connected to the cam 107. The mounting groove 301 is slidably connected with the outer edge surface of the piston 1071. A movable groove 5 is also provided above the mounting hole 1011, and a locking spring 501 and a sealing block 502 are provided. Installed in the movable groove 5, the front and rear ends of the locking spring 501 are respectively connected to the inner wall of the movable groove 5 and the rear side of the sealing block 502, and the locking shaft 503 is also slidably connected in the movable plate 1062. The inner wall of the extrusion cylinder 1 is connected to the locking shaft 503 through the second locking spring 5031, and the locking shaft 503 abuts against the sealing block 502. The sliding block 302 is provided with a second through hole 3021, and the locking shaft 503 passes through the second through hole 3021. The mounting hole 1011 is connected to the movable groove 5. The locking pin 504 is slidably connected in the movable groove 5, and inclined surfaces 505 are provided on the upper and lower ends of the locking pin 504 shaft and the rear end surface of the sealing block 502. The upper and lower inclined surfaces 505 of the locking pin 504 respectively abut against the inclined surfaces 505 on the rear end surface of the sealing block 502 and the plug rod 202. The guide groove 3012 is opened at the open end of the mounting groove 301, and the outer wall of the sliding block 302 is fitted with the guide groove 3012, and the guide groove 3012 is in the shape of an inner arc away from the sliding block 302.

[0040] See also Figures 1 to 8Due to the characteristics of the ultra-high molecular weight polyethylene material itself, the molten material has poor fluidity, so it is not easy to turn over and stir during the transportation process, which will cause a large heat difference between the upper and lower parts. In addition, the ultra-high molecular weight polyethylene has strong adhesion, so it is easy to adhere to the outer wall of the screw due to the temperature difference when flowing in the extrusion barrel 1. Because the waste adhered to the twin screws 102 increases, the gap between the extrusion barrel 1 and the twin screws 102 decreases, causing the pressure in the extrusion barrel 1 to rise. The pressure in the extrusion barrel 1 reaches the deformation value of the reset spring 203, thereby moving the gear 201, and realizing the connection with the belt group 105 through a large magnetic force. 1 is coupled, thereby driving the screw 105 to rotate, thereby reducing the setting of external power, and the structure is simple, which can effectively reduce the manufacturing cost of the extrusion device, and the meshing setting of the gear 201 and the output end of the motor 104 can increase the rotation speed of the screw 105 by setting the transmission ratio of the gear 201, thereby ensuring that the scraping component 3 can scrape the outer wall of the twin screw 102 along with the threads on the twin screw 102, and by manually turning the adjusting screw 2041, it is possible to flexibly control the plug rod 202 under different rated pressures, so that the gear 201 transmits the power of the motor 104 to The screw rod 105 is mounted on the drive wheel 105, thereby avoiding the slight fluctuation of the pressure in the extruder barrel 1, so that the scraping component 3 is started when the pressure does not meet the rated pressure, which interferes with the heating and melting of the material, and improves the stability and accuracy of the driving component 2. The gear 201 on it is meshed with the output tooth 1041 of the motor 104 and moves toward the driving wheel until the tooth surface is coupled with the belt group 1051. The motor 104 transmits power to the driving wheel through the magnetic connection between the gear 201 and the rotor of the driving wheel. The driven wheel drives the screw rod 105 to rotate due to the rotation of the belt. Due to the rotation of the screw rod 105 by the belt group 1051 It is unidirectional, and a reciprocating thread 1052 is provided at the connection between the screw rod 105 and the belt assembly 1051. The reciprocating thread 1052 is the reciprocating movement distance of the slider 106. A plurality of sliders 106 are arranged in an array on the rotating teeth 1053, thereby realizing the reciprocating movement of the slider 106, and the slider 106 is fitted with the extrusion barrel 1 through the arc surface 1061, so that the extension direction of the scraper 3026 of the slider 106 is always located above the twin screw 102 during the movement, thereby ensuring that the scraper 3026 is always located on the intersection line of the threads of the twin screw 102 while moving on the outer surface of the twin screw 102;At the same time, in order to ensure the compactness and sealing of the space in the extruder barrel 1, a moving plate 1062 is installed between the plurality of sliders 106, and the moving plate 1062 slides in contact with the upper end surface of the inner plate 1063 while the screw rod 105 moves, and the scraper 3026 extends from the scraping groove 1064, thereby ensuring the compactness of the space in the extruder barrel 1 and the sealing of the space. The contact between the moving plate 1062 and the inner plate 1063 prevents the material from entering the slider 106, and the rotation of the screw rod 105 The cam 107 then drives the scraper assembly 3 to reciprocate while rotating, and the scraper 3026 on it extends from the mounting groove 301, thereby achieving the purpose of scraping off the waste material adhering to the twin screw 102. After the waste material is scraped off, the pressure in the extruder 1 is reduced, and the plug rod 202 is reset to reduce the torque of the gear 201 and the belt group 1051, thereby cutting off the power. The scraper 3026 retracts into the scraper assembly 3 because the cam 107 stops, thereby ensuring that the scraper 3026 does not interfere with subsequent materials. ;

[0041] When the friction between the plug rod 202 and the inner wall of the mounting hole 1011 causes its sealing performance to decrease, by arranging a sealing ring 403 and an eardrum 4 in the mounting hole 1011, the eardrum 4 will deform into the mounting hole 1011 when under pressure, and by arranging the sealing ring 403, the sliding stroke of the plug rod 202 is guaranteed when under pressure, and after long-term use, the wear and tear caused by the friction with the inner wall of the mounting hole 1011 will not affect the sensitivity of the drive component 2, thereby ensuring that the cleaning effect of the twin screw 102 is still guaranteed after the extrusion device is used for a long time.

[0042] When the pressure in the extruder 1 increases to the rated value, that is, when the screw 105 rotates, the cam teeth 1073 meshing therewith rotate synchronously, and the cam 107 connected to the cam teeth 1073 rotates in the slideway 3011 accordingly. The crank 1072 is connected to the piston 1071. As the cam 107 rotates, the three form a crank 1072 connecting rod mechanism. As the piston 1071 reciprocates up and down in the slideway 3011, the sliding block 302 is pushed by the piston 1071 and moves toward the outside of the opening of the mounting groove 301, thereby causing the scraper 3026 to extend out of the mounting groove 301. Since the sliding block 302 and the mounting groove 301 are interference fit, the pulling force of the scraper spring 303 has a slow reset speed on the sliding block 302, and the movable plate 1062 is subjected to pressure to resist the elastic force of the locking spring 501 and moves toward the movable plate 1062. The movable plate 1062 moves in the movable groove 5, and the reciprocating distance of the movable plate 1062 in the movable groove 5 is equal to the length of the reciprocating thread 1052. The locking shaft 503 is subjected to the pulling force of the second locking spring 5031 and abuts against the sealing block 502. During the displacement of the locking shaft 503, the sliding block 302 completely extends out of the mounting groove 301. The locking shaft 503 is displaced due to the change in pressure and then completely penetrates the second through hole 3021 on the sliding block 302. Since the reaction force applied by the twin screw 102 to the scraper 3026 can only be transmitted upward along the mounting groove 301, and the displacement direction of the locking shaft 503 is 90° to the direction of the reaction force, the sliding block 302 will not be unlocked due to the reaction force after being locked, so that the position of the sliding block 302 can be fixed in real time, thereby achieving the scraping of waste on the twin screw 102;At the same time, in order to prevent the pressure in the extruder barrel 1 from fluctuating due to the gradual reduction of waste on the double threads during the scraping process of the scraper 3026, the return spring 203 is not deformed enough, and the plug rod 202 moves back and forth in the mounting hole 1011, resulting in insufficient torque between the gear 201 and the belt group 1051. When the plug rod 202 moves into the mounting hole 1011, the locking pin 504 shaft abuts against the outer edge of the plug rod 202, and the locking pin 504 cannot fall. The upper end of the locking pin 504 abuts against the rear end of the sealing block 502. When the displacement distance is at the pressure setting value, the locking pin 504 falls completely and abuts against the head of the plug rod 202, thereby limiting the displacement of the plug rod 202, thereby ensuring the coupling of the gear 201 and the belt group 1051, and the locking pin 504 shaft no longer abuts against the sealing block 502. The sealing block 502 is subjected to pressure and the thrust of the second locking spring 5031 on the locking shaft 503 and moves into the movable groove 5, thereby ensuring that the locking shaft 503 locks the scraper 3026 only after it is fully extended out of the installation groove 301, thereby avoiding the locking shaft 503 and the sliding block The hard friction of the outer wall of 302, when the pressure is completely reduced, the sealing block 502 and the plug rod 202 cooperate with the inclined surface 505 to release the lock of the plug rod 202, thereby ensuring the service life of the scraper 3026 and the sealing performance of the sliding block 302 and the mounting groove 301. In order to prevent the sliding block 302 and the scraper 3026 from adhering too much material to the outer wall after scraping the waste on the twin screw 102, causing the waste to solidify in the mounting groove 301, an inner arc-shaped guide groove 3026 is provided at the open end of the mounting groove 301 in a direction away from the sliding block 302. 12. When the scraper 3026 is reset due to the pulling force of the scraper spring 303, the materials on the sliding block 302 and the scraper 3026 are relative to the gap between the sliding block 302 and the mounting groove 301, so that the materials are more likely to enter the guide groove 3012, and the material is guided away from the mounting groove 301 by the setting of the inner arc. In addition, due to the pulling force of the scraper spring 303, the material obtains initial power when it is squeezed out of the guide groove 3012, thereby preventing the material from being retained in the guide groove 3012, thereby ensuring the cleaning effect of the scraper 3026 when scraping the twin screw 102. ;

[0043] A specific embodiment of the present invention is described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above described embodiment. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments without departing from the principles and ideas of the present invention should still fall within the scope of protection of the present invention.

Claims

1. An extrusion device for producing ultra-high molecular weight polyethylene pipes, comprising an extrusion barrel (1), a twin screw (102) and a heating ring (103), wherein the heating ring (103) is evenly distributed on the outer wall of the extrusion barrel (1), the twin screw (102) is rotatably installed in the extrusion barrel (1), and a motor (104) connected to the twin screw (102) is further provided at the rear end of the extrusion barrel (1), characterized in that: The inner wall of the extrusion barrel (1) is provided with a mounting hole (1011) and a through hole (1012), the through hole (1012) and the mounting hole (1011) are located directly above the motor (104), a screw rod (105) is installed in the through hole (1012), a belt group (1051) is provided on the screw rod (105), a drive assembly (2) is provided in the mounting hole (1011), a gear (201) is further provided on the drive assembly (2), the gear (201) is connected to the output end of the motor (104), and the drive assembly (1051) is provided with a belt group (1051) on the belt group (1051). The component (2) controls the tooth surface of the gear (201) to be connected to the belt group (1051) through the change of the pressure in the extruder barrel (1), and transmits the power of the motor (104) to the screw rod (105) through friction. The screw rod (105) is also provided with a plurality of sliders (106) and cams (107). The sliders (106) are provided with a scraping assembly (3). The scraping assembly (3) is also provided with a scraper (3026). When the cam (107) rotates, the scraper (3026) of the scraping assembly (3) moves onto the twin screw rod (102).

2. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 1, characterized in that: The driving assembly (2) further comprises a plug rod (202), a return spring (203) and a transmission part (204); the plug rod (202) is slidably mounted in the mounting hole (1011); the upper and lower ends of the plug rod (202) are respectively connected to the inner wall of the extrusion cylinder (1) and the transmission part (204); the upper and lower ends of the return spring (203) are respectively connected to the transmission part (204) and the mounting hole (1011); the transmission part (204) is located in the mounting hole (1011) and is connected to the gear (201).

3. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 2, characterized in that: The screw rod (105) is also provided with a reciprocating thread (1052) and a rotating tooth (1053), the reciprocating thread (1052) is located outside the extrusion barrel (1) and is rotatably matched with the belt group (1051), a plurality of sliders (106) are arranged in an array on the rotating tooth (1053), the slider (106) is provided with an arc surface (1061), a movable plate (1062) and an inner plate (1063), the arc surface (1061) is in contact with the extrusion barrel (1), the movable plate (1062) is installed at the lower end of the slider (106), the inner plate (1063) is installed in the extrusion barrel (1) and the movable plate (1062) is slidably connected, and a scraping groove (1064) is also provided on the inner plate (1063), and the scraping groove (1064) is slidably connected to the slider (106).

4. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 3, characterized in that: The scraping assembly (3) further comprises a mounting groove (301), a sliding block (302) and a scraping spring (303); the mounting groove (301) is provided in the sliding block (106) and the opening of the mounting groove (301) is located on the vertical projection surface of the twin screw (102); the sliding block (302) is slidably mounted in the mounting groove (301); the upper and lower ends of the scraping spring (303) are respectively connected to the mounting groove (301) and the sliding block (302) is connected, the scraper (3026) is connected to the sliding block (302), a slideway (3011) is also provided on the inner wall of the mounting groove (301), the cam (107) is installed in the slideway (3011), the cam (107) is also provided with a piston (1071), a crank (1072) and a cam tooth (1073), the upper and lower ends of the crank (1072) are respectively connected to the piston (1071) and the cam (107). The cam teeth (1073) are meshed with the rotating teeth (1053) and are fixedly connected to the cam (107). The outer edge surface of the piston (1071) is slidably connected to the mounting groove (301). A movable groove (5) is also provided above the mounting hole (1011). A locking spring (501) and a sealing block (502) are installed in the movable groove (5). The front and rear ends of the locking spring (501) are respectively connected to the inner surface of the movable groove (5). The wall is connected to the rear side of the sealing block (502), and a locking shaft (503) is also slidably connected inside the movable plate (1062). The inner wall of the extrusion cylinder (1) is connected to the locking shaft (503) through a second locking spring (5031), and the locking shaft (503) abuts against the sealing block (502). A second through hole (3021) is opened on the sliding block (302), and the locking shaft (503) passes through the second through hole (3021).

5. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 2, characterized in that: The movable groove (5) is connected to the mounting hole (1011), and a locking pin (504) is slidably connected in the movable groove (5). Inclined surfaces (505) are provided on the upper and lower ends of the locking pin (504) axis and the rear end surface of the sealing block (502). The upper and lower inclined surfaces (505) of the locking pin (504) respectively abut against the inclined surfaces (505) on the rear end surface of the sealing block (502) and the plug rod (202).

6. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 2, characterized in that: One side of the transmission part (204) is also provided with an adjusting screw (2041), an adjusting spring (2042) and an adjusting disk (2043); the adjusting disk (2043) is arranged in the mounting hole (1011) and is threadedly connected to the adjusting screw (2041); the adjusting spring (2042) is sleeved on the adjusting screw (2041) and has two ends respectively abutting against the transmission part (204) and the inner wall of the mounting hole (1011).

7. An extrusion device for producing ultra-high molecular weight polyethylene pipes according to claim 4, characterized in that: A guide groove (3012) is also provided at the open end of the installation groove (301), and the guide groove (3012) is in contact with the outer wall of the sliding block (302), and the guide groove (3012) is in an inner arc shape away from the sliding block (302).

8. According to the extrusion device for producing ultra-high molecular weight polyethylene pipes as described in claim 2, a tympanic membrane (4) and a sealing ring (403) are also provided on the inner wall of the mounting hole (1011) facing the extrusion barrel (1), and the two ends of the tympanic membrane (4) are respectively abutted against the sealing ring (403) and the plug rod (202), and the tympanic membrane (4) includes a fixing part (401) and a deformation part (402), and the fixing part (401) and the sealing ring (403) are both fixed in the mounting hole (1011), and the deformation part (402) is abutted against the plug rod (202) and isolates the polyethylene in the extrusion barrel (1).

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