Extrusion equipment for tpu car cover production line

Abstract

The application discloses an extrusion device for a TPU car cover production line, which comprises a rack, a cylinder, an extrusion screw, a driving mechanism and an extrusion die; the extrusion screw comprises a rod body extending in the front-rear direction and a screw thread extending spirally; the rod body comprises, in sequence from front to back, a feeding section, a plasticizing section, a first homogenizing section, a barrier section and a second homogenizing section; the screw thread forms a first material groove and a second material groove which extend spirally from front to back in the plasticizing section respectively; the depths of the first material groove and the second material groove gradually decrease from front to back in the plasticizing section; the plasticizing section comprises a first subsection and a second subsection with a length greater than six times the length of the first subsection; the widths of the first material groove and the second material groove gradually increase from front to back in the first subsection and remain unchanged from front to back in the second subsection; the length of the plasticizing section is greater than one third of the length of the rod body and less than one half of the length of the rod body; and the screw structure is specially designed for polyurethane elastomers, thereby improving the yield and plasticizing effect.

Description

Technical Field

[0001] This application relates to the field of automotive coating film production equipment technology, and in particular to an extrusion device for a TPU automotive coating production line. Background Technology

[0002] TPU car wrap film is a plastic film made of polyurethane elastomer. Currently, most extrusion equipment used to produce TPU car wraps suffers from varying degrees of insufficient plasticization, low output, numerous crystal impurities on the surface of the product, and unsatisfactory surface smoothness, which affects production efficiency, wastes a large amount of raw materials, and increases production costs. Summary of the Invention

[0003] In order to solve the above-mentioned technical problems, the purpose of this application is to provide an extrusion device for a TPU car cover production line.

[0004] To achieve the above objectives, this application adopts the following technical solution: an extrusion device for a TPU car cover production line, comprising a frame capable of reciprocating in a front-to-back direction, a barrel extending in a front-to-back direction, an extrusion screw rotatably installed within the barrel, a drive mechanism installed at the front end of the barrel, and an extrusion die suspended at the rear side of the frame. The drive mechanism is kinetically connected to the extrusion screw to drive the extrusion screw to rotate. The barrel has a feed inlet and a discharge outlet, and the extrusion die is connected to the discharge outlet. The extrusion screw includes a rod extending in a front-to-back direction and a thread extending helically from front to back on the rod. The rod, from front to back, consists of a feed section, a plasticizing section, a first homogenizing section, a barrier section, and a second homogenizing section. The outer diameter of the thread is uniformly and invariably distributed in the feed section, plasticizing section, first homogenizing section, and second homogenizing section. The aforementioned thread forms a first material groove and a second material groove extending spirally from front to back in the plasticizing section. The first material groove and the second material groove are arranged alternately from front to back. The volume of the second material groove is greater than the volume of the first material groove. The depth of the first material groove and the second material groove gradually decreases from front to back in the plasticizing section. The plasticizing section includes a first segment connected to the feeding section and a second segment connected to the first homogenizing section. The length of the second segment is greater than six times the length of the first segment. In the first segment, the width of the first material groove and the second material groove gradually increases from front to back. In the second segment, the width of the first material groove and the second material groove remains equal from front to back. The length of the plasticizing section is greater than one-third of the length of the rod and less than one-half of the length of the rod.

[0005] In the above technical solution, it is further preferred that the lead and root diameter of the thread in the first homogenization section are equal to the lead and root diameter of the thread in the second homogenization section, and the lead and root diameter of the thread in the first homogenization section are greater than the lead and root diameter of the thread in the feed section.

[0006] In the above technical solution, it is further preferred that the first feed groove divides the thread into a first main edge and a second main edge. In the second segment, the lead of the first main edge and the lead of the second main edge are equal, and the lead of the first main edge in the second segment is greater than the lead of the thread in other segments.

[0007] In the above technical solution, it is further preferred that the barrier section includes a plurality of feed troughs and a plurality of discharge troughs arranged alternately along the circumference of the rod, the plurality of feed troughs and the plurality of discharge troughs being parallel to each other, and the feed troughs having an inclined angle of 30°-60° with the axis of the rod.

[0008] In the above technical solution, a further preferred embodiment is that the extrusion equipment further includes a movable base frame that can be moved back and forth on the frame in the front-to-back direction and a hanger that is fixedly installed on the frame. The barrel and the drive mechanism are installed on the base frame. The rear half of the hanger is suspended on the rear side of the frame. The extrusion die is movable in the left-to-right direction and suspended below the hanger.

[0009] In the above technical solution, a further preferred embodiment is that a first moving mechanism is installed at the bottom of the frame. The first moving mechanism includes a first guide rail and a rack extending in the front-rear direction, a plurality of first moving gear trains and a plurality of gears rotatably installed at the bottom of the frame, and a moving motor that is connected to the plurality of gears in a transmission. The rack and the first guide rail are arranged side by side, the plurality of first moving gear trains are in rolling engagement with the first guide rail, and the plurality of gears mesh with the rack.

[0010] In the above technical solution, a further preferred embodiment is that a second moving mechanism is connected between the movable base and the frame. The second moving mechanism includes a second guide rail extending in the front-rear direction and a plurality of second moving wheel systems rotatably mounted on the bottom of the movable base. The second guide rail is mounted on the top of the frame, and the plurality of second moving wheel systems are in rolling cooperation with the second guide rail.

[0011] In the above technical solution, a further preferred embodiment is that a magnetic frame and a cooling device are installed at the feed inlet, with the magnetic frame positioned above the feed inlet and the cooling device surrounding the feed inlet.

[0012] In the above technical solution, a further preferred embodiment is that a screen changer, a metering pump, and a melt filter are connected sequentially between the discharge port and the extrusion die, and the screen changer, metering pump, and melt filter are all installed on the hanger.

[0013] In the above technical solution, a further preferred embodiment is that multiple temperature control units are installed on the barrel from front to back. Each temperature control unit includes a temperature detection device, a temperature adjustment device, and a temperature controller. The temperature detection device and the temperature adjustment device are both signal-connected to the temperature controller. Each temperature adjustment device includes a ceramic heating ring surrounding the barrel and a cooling fan facing the surface of the barrel. The ceramic heating ring and the cooling fan are both signal-connected to the corresponding temperature controller.

[0014] Compared with the prior art, this application achieves the following beneficial effects: The extrusion screw structure of this application is specially designed for polyurethane elastomers. The extrusion screw increases the feed rate of the extruder through the large lead thread in the feed section, thereby increasing the final output. The first and second feed troughs with uniform and constant widths over a long distance in the plasticizing section provide stable shearing and efficient forward conveying of the material, improving the plasticizing effect. The barrier section further plasticizes the uniformly mixed material between the two homogenizing sections, ensuring that the material is fully plasticized. The second homogenizing section thoroughly mixes the final extruded material, enabling the material to establish a stable extrusion pressure and reducing material extrusion fluctuations. Attached Figure Description

[0015] Figure 1 A front view of an extrusion device provided in an embodiment of this application; Figure 2 for Figure 1 Top view of the extrusion equipment in the middle; Figure 3 for Figure 1 Side view of the extrusion equipment in the middle; Figure 4 for Figure 3 A magnified view of a portion of point A in the middle; Figure 5 This is a schematic diagram of the structure of an extrusion screw for an extrusion device provided in an embodiment of this application; Figure 6 for Figure 5 A schematic diagram of the plasticizing section in the middle; Figure 7 for Figure 5 A schematic diagram of the barrier segment in the diagram.

[0016] Wherein: 100, extrusion equipment; 1, frame; 11, first moving mechanism; 111, first guide rail; 112, first moving gear train; 113, rack; 114, gear; 115, moving motor; 2, barrel; 21, magnetic frame; 3, extrusion screw; 31, rod body; 311, feeding section; 312, plasticizing section; 3121, first segment; 3122, second segment; 313, first homogenization section; 314, barrier section; 315 32. Second homogenization section; 33. Thread; 321. First feed trough; 322. Second feed trough; 323. First main edge; 324. Second main edge; 331. Feed trough; 332. Discharge trough; 333. Shear barrier; 4. Drive mechanism; 5. Extrusion die; 6. Moving base frame; 61. Second moving mechanism; 611. Second guide rail; 612. Second moving wheel system; 7. Hanger; 81. Screen changer; 82. Metering pump; 83. Melt filter. Detailed Implementation

[0017] To illustrate the technical content, structural features, achieved objectives, and effects of the application in detail, the technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. In the following description, for illustrative purposes, numerous specific details are set forth to provide a detailed description of various exemplary embodiments or implementations of the invention. However, various exemplary embodiments may also be implemented without these specific details or in one or more equivalent arrangements. Furthermore, the various exemplary embodiments may differ, but are not necessarily exclusive. For example, the specific shape, structure, and characteristics of the exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0018] This application provides an extrusion device for a TPU car cover production line, such as... Figure 1-3 As shown, the extrusion equipment 100 includes a frame 1 that can move back and forth in the front-back direction, a barrel 2 that extends in the front-back direction, an extrusion screw 3 that is rotatably installed in the barrel 2, a drive mechanism 4 installed at the front end of the barrel 2, and an extrusion die 5 suspended at the rear side of the frame 1. The drive mechanism 4 is connected to the extrusion screw 3 to drive the extrusion screw 3 to rotate around its own axis X1 in the barrel 2, thereby plasticizing and melting the material into a melt for extrusion.

[0019] The barrel 2 has a feed port for material entry and a discharge port for fully plasticized melt extrusion, and the extrusion die 5 is connected to the discharge port.

[0020] like Figure 5As shown, the extrusion screw 3 includes a rod body 31 extending in the front-to-back direction and a thread 32 extending helically on the rod body 31 from front to back. The rod body 31 consists of a feeding section 311, a plasticizing section 312, a first homogenizing section 313, a barrier section 314, and a second homogenizing section 315 from front to back. The outer diameter of the thread 32 is evenly and continuously distributed in the feeding section 311, the plasticizing section 312, the first homogenizing section 313, and the second homogenizing section 315.

[0021] The length of the plasticizing section 312 is greater than one-third of the length of the rod 31 and less than one-half the length of the rod 31. The plasticizing section 312 is the longest segment. The length of the barrier section 314 is less than the length of the other segments. The length of the second homogenizing section 315 is less than the length of the first homogenizing section 313.

[0022] In the feeding section 311, the lead S1 and root diameter D1 of the thread 32 remain constant from front to back. In the first homogenization section 313, the lead S3 and root diameter D3 of the thread 32 remain constant from front to back. In the second homogenization section 315, the lead S5 and root diameter D5 of the thread 32 remain constant from front to back. Wherein, S3=S5, D3=D5, S3>S1, and D3>D1. The first homogenization section 313 mixes the material uniformly between the plasticizing section 312 and the barrier section 314, improving the plasticizing efficiency of the barrier section 314. The uniform threads in the second homogenization section 315 thoroughly mix the material and establish a stable extrusion pressure, reducing pressure fluctuations in the material and improving the surface smoothness of the extruded product.

[0023] like Figure 6 As shown, the thread 32 forms a first material groove 321 and a second material groove 322 extending spirally from front to back in the plasticizing section 312, respectively. The volume of the second material groove 322 is always greater than the volume of the first material groove 321. In the direction from front to back, the first material groove 321 and the second material groove 322 are arranged alternately, and the depth of both the first material groove 321 and the second material groove 322 gradually decreases.

[0024] The plasticizing section 312 includes a first segment 3121 connected to the feeding section 311 and a second segment 3122 connected to the first homogenizing section 313. The length of the second segment 3122 is more than six times the length of the first segment 3121. The first feed trough 321 divides the thread 32 into a first main ridge 323 and a second main ridge 324. In the second segment 3122, the lead S of the first main ridge 323... 21 The lead S of the second principal edge 324 22 Equal, and the lead S of the first principal edge 323 in the second segment 3122 is equal. 21The lead of thread 32 is greater than that of other sections. In the first section 3121, the width of the first feed trough 321 and the second feed trough 322 gradually increases from front to back; in the second section 3122, the widths of the first feed trough 321 and the second feed trough 322 formed by the first main edge 323 and the second main edge 324 with equal leads remain constant from front to back. In the plasticizing section 312, the widths of most of the first feed trough 321 and the second feed trough 322 remain constant, only the depth of the troughs gradually becomes shallower. On the one hand, this separates the plasticized melt from the unplasticized solid; on the other hand, because the depth gradually decreases, the volume of each trough gradually decreases from front to back, thereby compressing the melt and solid, so that the solid material is plasticized and melted, and the melt material is further fully plasticized.

[0025] like Figure 7 As shown, the barrier section 314 includes multiple feed troughs 331 and multiple discharge troughs 332 arranged alternately along the circumference of the rod 31. The feed troughs 331 and the discharge troughs 332 are parallel to each other, and the feed troughs 331 have an inclined angle α of 30°-60° with the axis X1 of the rod 31. In the rotation direction of the extrusion screw 3, a shear barrier 333 is formed between each feed trough 331 and the downstream discharge trough 332. When the material crosses the shear barrier 333 from the feed trough 331 and enters the discharge trough 332, it is subjected to severe shearing by the shear barrier 333, further plasticizing and melting, and improving the plasticizing effect.

[0026] like Figure 1-4 As shown, the extrusion equipment 100 also includes a movable base frame 6 mounted on the frame 1 and a hanger 7 fixedly mounted on the frame 1, which can move back and forth in the front-to-back direction. A first moving mechanism 11 is mounted on the bottom of the frame 1. The first moving mechanism 11 includes a first guide rail 111 and a rack 113 extending in the front-to-back direction, a plurality of first moving gear trains 112 and a plurality of gears 114 rotatably mounted on the bottom of the frame 1, and a moving motor 115 driven by the plurality of gears 114. The first guide rail 111 and the rack 113 are arranged side-by-side. The plurality of first moving gear trains 112 are in rolling engagement with the first guide rail 111, and the plurality of gears 114 mesh with the rack 113. The moving motor 115 drives the plurality of gears 114 to rotate. The frame 1 moves in the front-to-back direction due to the opposing force between the gears 114 and the rack 113. The cooperating first moving gear trains 112 and the first guide rail 111 reduce the friction between the frame 1 and the ground, allowing the frame 1 to move smoothly in the front-to-back direction.

[0027] A second moving mechanism 61 is installed between the bottom of the movable base 6 and the frame 1. The second moving mechanism 61 includes a second guide rail 611 extending in the front-rear direction and a plurality of second moving wheel systems 612 rotatably mounted on the bottom of the movable base 6. The plurality of second moving wheel systems 612 are in rolling engagement with the second guide rail 611. The movable base 6 can move in the front-rear direction on the frame 1 through the mutually cooperating second moving wheel systems 612 and second guide rail 611. The barrel 2 and the drive mechanism 4 are mounted on the movable base 6 and can move in the front-rear direction through the movable base 6, thereby disengaging from the extrusion die 5 for easy maintenance and cleaning.

[0028] The rear half of the hanger 7 is suspended above the rear of the frame 1 to support the extrusion die 5, thus suspending the extrusion die 5 above the rear of the frame 1. The extrusion die 5 is a split die, consisting of a detachably connected upper die and a lower die. Both the upper and lower dies are movable on the hanger 7 in the left and right directions. When cleaning the extrusion die 5, simply open the upper and lower dies in the left and right directions; the operation is simple and convenient. The first moving mechanism 11 at the bottom of the frame 1 allows the frame 1 and the extrusion die 5 suspended at the rear of the frame 1 to move back and forth, thereby adjusting the position of the extrusion die 5 in the front and back directions so that the extrusion die 5 can be moved into and out of the corresponding molding equipment.

[0029] A magnetic frame 21 and a cooling device (not shown in the figure) are installed at the feed inlet. The magnetic frame 21 is mounted above the feed inlet to effectively prevent metal impurities from entering the barrel 2. The cooling device surrounds the feed inlet to reduce the temperature at the feed inlet and prevent material bridging caused by excessively high feed inlet temperature. In this embodiment, the cooling device is a cooling channel formed on the wall of the barrel 2, which is connected to an external cooling water source to allow cooling water to flow in, thereby reducing the temperature at the feed inlet.

[0030] To ensure melt quality, multiple temperature control units are installed on the barrel 2 from front to back. Each temperature control unit includes a temperature detection device (not shown in the figure), a temperature regulating device (not shown in the figure), and a temperature controller (not shown in the figure). The temperature detection device and the temperature regulating device are both connected to the temperature controller. Each temperature regulating device includes a ceramic heating coil 91 surrounding the barrel 2 and a cooling fan 82 facing the surface of the barrel 2. The ceramic heating coil 91 and the cooling fan 92 are both connected to the corresponding temperature controller. The temperature detection device detects the temperature of the corresponding area of ​​the barrel 2 and transmits the detected temperature to the corresponding temperature controller. The temperature controller controls the operation of the ceramic heating coil 91 and the cooling fan 82 based on the temperature detection results, thereby regulating the temperature of the corresponding area of ​​the barrel 2. Multiple temperature control units provide zoned temperature control for the barrel 2, thereby achieving precise temperature control and improving the plasticizing effect on the material inside the barrel 2.

[0031] A screen changer 81, a metering pump 82, and a melt filter 83 are sequentially connected between the discharge port and the extrusion die 5. All three are mounted on the hanger 7. The screen changer 81 filters impurities from the melt output from the discharge port of the barrel 2. The metering pump 82 regulates the flow rate of the extruded melt to ensure a uniform and stable supply of melt to the extrusion die 5. The melt filter 83 further filters the melt to ensure that the extruded product from the extrusion die 5 is free of impurities, effectively improving product quality.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this application. Various changes and modifications can be made without departing from the spirit and scope of this application. The scope of protection claimed by this application is defined by the appended claims, specification, and their equivalents.

Claims

1. An extrusion device for a TPU car cover production line, comprising a frame capable of reciprocating in a front-to-back direction, a barrel extending in the front-to-back direction, an extrusion screw rotatably mounted within the barrel, a drive mechanism mounted at the front end of the barrel, and an extrusion die suspended at the rear side of the frame, wherein the drive mechanism is tractively connected to the extrusion screw to drive the extrusion screw to rotate, the barrel having an inlet and an outlet, and the extrusion die communicating with the outlet; characterized in that, The extrusion screw includes a rod extending in a front-to-back direction and a thread extending helically from front to back on the rod. The rod, from front to back, consists of a feed section, a plasticizing section, a first homogenizing section, a barrier section, and a second homogenizing section. The outer diameter of the thread is uniformly distributed across the feed section, plasticizing section, first homogenizing section, and second homogenizing section. In the plasticizing section, the thread forms a first material groove and a second material groove, respectively, extending helically from front to back. The first material groove and the second material groove are arranged alternately from front to back. The volume of the second material groove is larger than the volume of the first material groove. The depth of the second material trough gradually decreases from front to back in the plasticizing section; the plasticizing section includes a first segment connected to the feeding section and a second segment connected to the first homogenizing section, the length of the second segment is greater than six times the length of the first segment, in the first segment, the width of the first material trough and the second material trough gradually increases from front to back, in the second segment, the width of the first material trough and the second material trough remain equal from front to back; the length of the plasticizing section is greater than one-third of the length of the rod and less than one-half the length of the rod.

2. The extrusion equipment according to claim 1, characterized in that, The lead and root diameter of the thread in the first homogenization section are equal to those of the thread in the second homogenization section, and the lead and root diameter of the thread in the first homogenization section are greater than those of the thread in the feed section.

3. The extrusion equipment according to claim 2, characterized in that, The first feed groove divides the thread into a first main edge and a second main edge. In the second segment, the lead of the first main edge and the lead of the second main edge are equal, and the lead of the first main edge in the second segment is greater than the lead of the thread in other segments.

4. The extrusion equipment according to claim 1, characterized in that, The barrier section includes multiple feed troughs and multiple discharge troughs arranged alternately along the circumference of the rod. The multiple feed troughs and multiple discharge troughs are parallel to each other, and the feed troughs have an inclined angle of 30°-60° with the axis of the rod.

5. The extrusion equipment according to claim 1, characterized in that, The extrusion equipment further includes a movable base frame that can be moved back and forth on the frame in the front-to-back direction and a hanger that is fixedly mounted on the frame. The barrel and the drive mechanism are mounted on the base frame. The rear half of the hanger is suspended on the rear side of the frame. The extrusion die is suspended below the hanger in the left-to-right direction.

6. The extrusion equipment according to claim 5, characterized in that, The bottom of the frame is equipped with a first moving mechanism, which includes a first guide rail and a rack extending in the front-rear direction, a plurality of first moving gear trains and a plurality of gears rotatably mounted on the bottom of the frame, and a moving motor that is connected to the plurality of gears in a transmission. The rack and the first guide rail are arranged side by side, the plurality of first moving gear trains are in rolling engagement with the first guide rail, and the plurality of gears mesh with the rack.

7. The extrusion equipment according to claim 6, characterized in that, A second moving mechanism is connected between the movable base and the frame. The second moving mechanism includes a second guide rail extending in the front-rear direction and a plurality of second moving wheel systems rotatably mounted on the bottom of the movable base. The second guide rail is mounted on the top of the frame, and the plurality of second moving wheel systems are in rolling cooperation with the second guide rail.

8. The extrusion equipment according to claim 1, characterized in that, A magnetic frame and a cooling device are installed at the feed inlet. The magnetic frame is erected above the feed inlet, and the cooling device surrounds the feed inlet.

9. The extrusion equipment according to claim 5, characterized in that, A screen changer, a metering pump, and a melt filter are sequentially connected between the discharge port and the extrusion die. The screen changer, metering pump, and melt filter are all mounted on the hanger.

10. The extrusion equipment according to claim 1, characterized in that, Multiple temperature control units are installed on the barrel from front to back. Each temperature control unit includes a temperature detection device, a temperature adjustment device, and a temperature controller. The temperature detection device and the temperature adjustment device are both connected to the temperature controller via signal connection. Each temperature adjustment device includes a ceramic heating ring surrounding the barrel and a cooling fan facing the surface of the barrel. The ceramic heating ring and the cooling fan are both connected to the corresponding temperature controller via signal connection.

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