Extrusion molding device and extrusion molding process of polytetrafluoroethylene rod

Abstract

The invention relates to the technical field of extrusion molding, in particular to an extrusion molding device for a polytetrafluoroethylene rod and an extrusion molding process of the extrusion molding device. And an extrusion cylinder; the extrusion molding cylinder is provided with a shaping pipe; a plunger is embedded in the extrusion molding cylinder in a sliding manner, and a second ejector rod is mounted on the plunger; an extrusion molding mechanism is arranged on the case, and the extrusion molding mechanism can drive the plunger to slide; a feeding cylinder is mounted on the case; an opening and closing groove is formed in the feeding cylinder; a sliding plate is embedded in the opening and closing groove in a sliding mode, and a notch is formed in the sliding plate. An opening and closing mechanism is arranged on the case and drives the sliding plate to slide so as to drive the notch to slide; a rotating rod is rotationally installed in the second ejector rod, a fixing block is installed on the rotating rod, and a scraper is installed on the fixing block. A cleaning mechanism is arranged on the case, and the extrusion molding mechanism acts to drive the cleaning mechanism to act so as to drive the scraper to rotate.

Description

Technical Field

[0001] The invention relates to the technical field of extrusion, in particular to an extrusion device for a polytetrafluoroethylene rod and an extrusion process thereof. Background Art

[0002] PTFE rod is a polymer material suitable for processing various gaskets, seals and lubricating materials working in corrosive media. This material has high corrosion resistance, high mechanical properties, high temperature resistance, and a wide range of operating temperatures, from -200°C to 260°C. These characteristics of PTFE rod make it perform well in many industrial applications, such as in the chemical, food processing, pharmaceutical, electronic and mechanical manufacturing industries. It is often used to make linings and coatings for pipes, valves, pumps and pipe fittings, as well as lubricating bearings, piston rings, oil seals and sealing rings. PTFE rod is a rod made of PTFE resin (which may contain recycled PTFE resin) through molding, paste extrusion or plunger extrusion.

[0003] Common extrusion devices include plunger extruders and screw extruders. Since polytetrafluoroethylene has a high melting point and high melt viscosity. Polytetrafluoroethylene (PTFE) has a melting point of up to 327°C and has extremely high viscosity in the molten state, which makes it difficult to handle in conventional thermoplastic molding processes. Therefore, screw extruders are not suitable for processing polytetrafluoroethylene rods.

[0004] The plunger extruder uses a plunger to discharge the material from the barrel through the die, and a hydraulic system is often used as the power source. When a plunger extruder is used to extrude polytetrafluoroethylene rods, due to the high viscosity of polytetrafluoroethylene, polytetrafluoroethylene will remain on the plunger after the extrusion is completed. As time goes by, the amount of residue will gradually increase, reducing the space in the barrel, thereby affecting the extrusion effect. The residual polytetrafluoroethylene makes the plunger surface no longer smooth, further affecting the extrusion effect. Summary of the invention

[0005] The object of the present invention is to provide a polytetrafluoroethylene rod extrusion device and an extrusion process thereof to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: A polytetrafluoroethylene rod extrusion device comprises a machine case; and an extrusion cylinder mounted on the machine case; a shaping tube is mounted on one end of the extrusion cylinder; A plunger is slidably embedded in the extrusion cylinder, and a second ejector rod is installed on the plunger; The chassis is provided with an extrusion mechanism, and the action of the extrusion mechanism can drive the second push rod to approach or move away from the shaping tube, so as to drive the plunger to slide in the extrusion cylinder toward or away from the shaping tube; A feed barrel is installed on the chassis; an opening and closing groove is provided on the feed barrel; a slide plate is slidably engaged on the opening and closing groove, and a notch is provided on the slide plate; The chassis is provided with an opening and closing mechanism, and the movement of the extrusion mechanism can drive the opening and closing mechanism to move, thereby driving the slide plate to slide in the opening and closing groove, thereby driving the notch to slide; A rotating rod is rotatably installed in the second push rod, a fixed block rotatably engaged with the plunger is installed on the rotating rod, and a scraper is installed on the fixed block; The chassis is provided with a cleaning mechanism, and the movement of the extrusion mechanism can drive the cleaning mechanism to move, so as to drive the rotating rod to rotate, thereby driving the scraper to rotate through the fixed block.

[0007] As a further solution of the present invention: the extrusion mechanism includes a hydraulic cylinder installed on the chassis, a piston is slidably embedded in the hydraulic cylinder, a first push rod is rotatably installed on the piston, and a force transmission plate fixedly connected to the second push rod is rotatably installed on the first push rod.

[0008] As a further solution of the present invention: the opening and closing mechanism includes a fixed sleeve installed on the extrusion cylinder, a sliding rod is slidably engaged in the fixed sleeve, a spring fixedly connected to the sliding rod is installed on the side of the fixed sleeve close to the force transmission plate, a connecting rod is installed on the other side of the sliding rod, a protruding column is installed on the connecting rod, and a matching groove slidably engaged with the protruding column is provided on the slide plate; a third push rod that can contact the sliding rod is installed on the second push rod.

[0009] As a further solution of the present invention: the matching groove includes a first transverse groove, a first oblique groove, a second transverse groove, and a second oblique groove; wherein the two ends of the second oblique groove are respectively connected with the first transverse groove and one end of the second transverse groove; one end of the first oblique groove is connected with the other end of the second transverse groove, and the other end of the first oblique groove is connected with the first transverse groove; a limit rod is rotatably installed on the slide plate, and a limit column matching with the limit rod is installed on the slide plate.

[0010] As a further solution of the present invention: the cleaning mechanism includes a raised column installed on the hydraulic cylinder, and the first push rod is provided with a spiral groove that slides and engages with the raised column; a large pulley is installed on the first push rod, a small pulley is rotatably installed on the force transmission plate, and the large pulley and the small pulley are connected by a belt; a ratchet wheel is installed on the small pulley; a mating wheel is installed on the rotating rod, and a plurality of ratchets that cooperate with the ratchet wheel are rotatably installed on the mating wheel.

[0011] As a further solution of the present invention: the scraper is arranged at an angle, and the scraper conflicts with the plunger.

[0012] As a further solution of the present invention: the aperture of the shaping tube is much smaller than the diameter of the extrusion cylinder, and the shaping tube is relatively long.

[0013] An extrusion process, comprising the extrusion device of the polytetrafluoroethylene rod as described above, comprising the following steps: The first step is to connect the feed barrel with the raw material storage bin; connect the hydraulic cylinder with the hydraulic system; start the hydraulic system; Step 2: The hydraulic system will inject hydraulic liquid into the hydraulic cylinder to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger away from the shaping tube through the second ejector rod. During the process of moving away, the opening and closing mechanism will drive the slide plate to slide outward in the opening and closing groove to drive the notch to slide, thereby connecting the feed barrel and the extrusion barrel, so that the raw materials flow into the extrusion barrel; Step 3: The hydraulic system draws out the hydraulic liquid in the hydraulic cylinder to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger to approach the shaping tube through the second ejector rod to extrude the raw material in the extrusion cylinder and extrude it from the shaping tube. The shaping tube can cool and shape the polytetrafluoroethylene to form a polytetrafluoroethylene rod. Step 4: The hydraulic system will inject hydraulic liquid into the hydraulic cylinder to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger away from the shaping tube through the second push rod. During the process of moving away, the cleaning mechanism drives the scraper to rotate through the rotating rod to clean the polytetrafluoroethylene stuck on the plunger, and drives the opening and closing mechanism to move again to extrude the next polytetrafluoroethylene rod.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the molding mechanism drives the plunger away from the molding tube through the second ejector rod; and drives the cleaning mechanism and the opening and closing mechanism to act simultaneously, and drives the scraper to rotate through the cleaning mechanism to scrape off the residual tetrafluoroethylene in the extrusion process of the previous polytetrafluoroethylene rod, so as to prevent the polytetrafluoroethylene sticking to the plunger from becoming more and more during the long-term extrusion process, thereby affecting the quality of the extruded finished product, and effectively improving the production efficiency; and in this process, the opening and closing mechanism will first keep the position of the slide unchanged (the slide blocks the position of the feed barrel and the extrusion barrel), and after the cleaning mechanism has worked for a period of time, the opening and closing mechanism drives the slide to slide, so as to connect the feed barrel and the extrusion barrel through the notch, so that the raw material enters the extrusion barrel, and after a certain amount of raw material is injected into the extrusion barrel, the slide is driven to slide in the opposite direction to block the feed barrel and the extrusion barrel; in this way, the cleaning efficiency of the cleaning mechanism can be effectively improved (preventing the newly injected raw material from sticking to the plunger when the scraper scrapes off the sticky polytetrafluoroethylene in the extrusion process of the previous polytetrafluoroethylene rod), and the production efficiency and extrusion quality can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention is a schematic structural diagram of an embodiment of a polytetrafluoroethylene rod extrusion device.

[0016] Figure 2 A schematic structural diagram of an embodiment of a polytetrafluoroethylene rod extrusion device from another perspective.

[0017] Figure 3 A schematic structural diagram of a cross-sectional view of an embodiment of a polytetrafluoroethylene rod extrusion device.

[0018] Figure 4 for Figure 3 Schematic diagram of the structure at A in the middle.

[0019] Figure 5 The present invention is a schematic structural diagram of an opening and closing mechanism in one embodiment of a polytetrafluoroethylene rod extrusion device.

[0020] Figure 6 for Figure 5 Schematic diagram of the structure from an exploded perspective.

[0021] Figure 7 for Figure 6 Schematic diagram of the structure at B in the figure.

[0022] Figure 8 The present invention is a schematic structural diagram of an extrusion mechanism in one embodiment of an extrusion device for polytetrafluoroethylene rods.

[0023] Fig. 9 for Figure 8 Schematic diagram of the structure at C in the middle.

[0024] Fig.10 for Figure 8 Schematic diagram of the structure from an exploded perspective.

[0025] Fig.11 The present invention is a schematic structural diagram of a second push rod and a rotating rod in one embodiment of a polytetrafluoroethylene rod extrusion device.

[0026] In the figure: 1. Chassis; 2. Extrusion cylinder; 3. Hydraulic cylinder; 301. Raised column; 4. Piston; 5. first push rod; 501. spiral groove; 6. Force transfer plate; 7. Second push rod; 701. Third push rod; 8. Plunger; 9. Feeding barrel; 901. Opening and closing slot; 10. Fixing sleeve; 11. sliding rod; 1101. connecting rod; 1102. protruding column; 12. Spring; 13. Slide plate; 1301. Notch; 1302. First transverse groove; 1303. First oblique groove; 1304. Second transverse groove; 1305. Second oblique groove; 1306. Limit rod; 1307. Limit column; 14. Large pulley; 15. Small pulley; 1501. Ratchet wheel; 16. Belt; 17. Rotating rod; 1701. Matching wheel; 1702. Ratchet; 1703. Fixed block; 1704. Scraper; 18. Shaping tube. DETAILED DESCRIPTION

[0027] 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.

[0028] In addition, when an element in the present invention is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0029] See also Figure 1 to Figure 11 In an embodiment of the present invention, a polytetrafluoroethylene rod extrusion device and an extrusion process thereof include a chassis 1; and an extrusion cylinder 2 mounted on the chassis 1; a shaping tube 18 is mounted on one end of the extrusion cylinder 2; A plunger 8 is slidably engaged in the extrusion cylinder 2, and a second ejector rod 7 is mounted on the plunger 8; The housing 1 is provided with an extrusion mechanism, and the action of the extrusion mechanism can drive the second push rod 7 to move closer to or away from the shaping tube 18, so as to drive the plunger 8 to slide closer to or away from the shaping tube 18 in the extrusion cylinder 2; The chassis 1 is provided with a feed barrel 9; an opening and closing groove 901 is provided on the feed barrel 9; a slide plate 13 is slidably engaged with the opening and closing groove 901, and a notch 1301 is provided on the slide plate 13; The chassis 1 is provided with an opening and closing mechanism, and the movement of the extrusion mechanism can drive the opening and closing mechanism to move, thereby driving the slide plate 13 to slide in the opening and closing groove 901, thereby driving the notch 1301 to slide; A rotating rod 17 is rotatably mounted in the second push rod 7, a fixed block 1703 rotatably engaged with the plunger 8 is mounted on the rotating rod 17, and a scraper 1704 is mounted on the fixed block 1703; The chassis 1 is provided with a cleaning mechanism, and the movement of the extrusion mechanism can drive the cleaning mechanism to move, so as to drive the rotating rod 17 to rotate, thereby driving the scraper 1704 to rotate through the fixed block 1703 .

[0030] Taking the embodiment combining all the features recorded in the present application as an example, when in use, the feed barrel 9 is connected to the raw material storage bin; the hydraulic cylinder 3 is connected to the hydraulic system; the hydraulic system is started; the hydraulic system will inject hydraulic liquid into the hydraulic cylinder 3 to drive the extrusion mechanism to move, and the extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7. During the moving away process, the opening and closing mechanism will drive the slide plate 13 to slide outward in the opening and closing groove 901 to drive the notch 1301 to slide, thereby connecting the feed barrel 9 and the extrusion barrel 2, so that the raw material flows into the extrusion barrel 2; after the amount of raw material injected into the extrusion barrel 2 reaches the requirement, the opening and closing mechanism will drive the slide plate 13 to slide inward in the opening and closing groove 901 to seal the feed barrel 9 and the extrusion barrel 2.

[0031] Afterwards, the hydraulic system draws out the hydraulic liquid in the hydraulic cylinder 3 to drive the extrusion mechanism to operate. The extrusion mechanism drives the plunger 8 to approach the shaping tube 18 through the second push rod 7 to extrude the raw material in the extrusion cylinder 2 and extrude it from the shaping tube 18. The shaping tube 18 can cool and shape the polytetrafluoroethylene to form a polytetrafluoroethylene rod; and in this process, the extrusion mechanism will drive the opening and closing mechanism to operate, reset the opening and closing mechanism, and maintain the blocked state.

[0032] The hydraulic system will inject hydraulic liquid into the hydraulic cylinder 3 to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7. During the moving away process, the cleaning mechanism drives the scraper 1704 to rotate through the rotating rod 17 to clean the polytetrafluoroethylene stuck on the plunger 8, and drives the opening and closing mechanism to move again to extrude the next polytetrafluoroethylene rod. At the same time, the locking mechanism will move to make the feed barrel 9 and the extrusion barrel 2 conductive.

[0033] The extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7; and drives the cleaning mechanism and the opening and closing mechanism to act simultaneously, and drives the scraper 1704 to rotate through the cleaning mechanism to scrape off the residual polytetrafluoroethylene in the extrusion process of the previous polytetrafluoroethylene rod, so as to prevent more and more polytetrafluoroethylene from sticking to the plunger 8 during the long-term extrusion process, thereby affecting the quality of the extruded product, and effectively improving the production efficiency; and in this process, the opening and closing mechanism will first keep the position of the slide plate 13 unchanged (the slide plate 13 blocks the position of the feed cylinder 9 and the extrusion cylinder 2), and then, in the cleaning process, After the cleaning mechanism has been working for a period of time, the opening and closing mechanism drives the slide plate 13 to slide, so as to connect the feed cylinder 9 and the extrusion cylinder 2 through the slot 1301, so that the raw material can enter the extrusion cylinder 2, and after a certain amount of raw material is injected into the extrusion cylinder 2, the slide plate 13 is driven to slide in the opposite direction to seal the feed cylinder 9 and the extrusion cylinder 2; thereby, the cleaning efficiency of the cleaning mechanism can be effectively improved (preventing the newly injected raw material from sticking to the plunger 8 when the scraper 1704 scrapes off the sticky polytetrafluoroethylene during the extrusion process of the previous polytetrafluoroethylene rod), and the production efficiency and extrusion quality can be improved.

[0034] In another embodiment of the present invention, the extrusion mechanism includes a hydraulic cylinder 3 installed on the chassis 1, a piston 4 is slidably engaged in the hydraulic cylinder 3, a first push rod 5 is rotatably installed on the piston 4, and a force transmission plate 6 fixedly connected to the second push rod 7 is rotatably installed on the first push rod 5.

[0035] Taking the embodiment combining all the features recorded in the present application as an example, when in use, when the hydraulic system injects hydraulic liquid into the hydraulic cylinder 3, as the injection amount of the hydraulic liquid increases, the hydraulic liquid will continuously squeeze the piston 4, causing it to slide in the hydraulic cylinder 3 toward the force transmission plate 6, and the sliding distance is directly related to the injection amount of the hydraulic liquid; when the piston 4 slides, it will drive the first push rod 5 to move synchronously, thereby driving the second push rod 7 to move synchronously through the force transmission plate 6, so as to drive the plunger 8 to gradually slide away from the shaping tube 18, thereby providing space for the injection of raw materials; at the same time, the opening and closing mechanism will act to connect the feed barrel 9 with the extrusion barrel 2, so that the raw material can be injected into the extrusion barrel 2.

[0036] Then, the hydraulic liquid in the hydraulic cylinder 3 is pumped out through the hydraulic system. As the hydraulic liquid continues to decrease, the piston 4 will gradually move away from the force transmission plate 6, thereby driving the plunger 8 to approach the shaping tube 18, so as to squeeze the raw material in the extrusion barrel 2 and extrude it through the shaping tube 18.

[0037] The extrusion mechanism can relatively simply provide extrusion force for the polytetrafluoroethylene rod extrusion process, thereby effectively improving production efficiency.

[0038] According to another embodiment of the present invention, the opening and closing mechanism includes a fixed sleeve 10 installed on the extrusion cylinder 2, a sliding rod 11 is slidably engaged in the fixed sleeve 10, a spring 12 fixedly connected to the sliding rod 11 is installed on the side of the fixed sleeve 10 close to the force transmission plate 6, a connecting rod 1101 is installed on the other side of the sliding rod 11, a protruding column 1102 is installed on the connecting rod 1101, and a matching groove slidably engaged with the protruding column 1102 is provided on the slide plate 13; a third push rod 701 that can contact the sliding rod 11 is installed on the second push rod 7.

[0039] Taking the embodiment combining all the features described in the present application as an example, when in use, in the initial state, the plunger 8 is located at the position with the minimum distance from the shaping tube 18. At this time, the third push rod 701 is in conflict with the slide rod 11, and the spring 12 is in a compressed state (a baffle is installed on the end of the slide rod 11 close to the third push rod 701, and the spring 12 is fixedly connected to the baffle).

[0040] In the process of the second push rod 7 driving the plunger 8 away from the shaping tube 18, the third push rod 701 will be displaced synchronously; under the elastic force of the spring 12, the baffle drives the slide bar 11 to slide in the fixed sleeve 10 toward the third push rod 701, thereby driving the protruding column 1102 to slide with the matching groove through the connecting rod 1101, thereby first driving the slide plate 13 to slide outward in the opening and closing groove 901, so that the slot 1301 can connect the feed barrel 9 and the extrusion barrel 2, and then the position of the slide plate 13 will remain unchanged to maintain the conductive state; after the raw material is injected into the extrusion barrel 2, the slide plate 13 is driven to slide inward in the opening and closing groove 901 through the sliding cooperation between the protruding column 1102 and the matching groove, so as to block the feed barrel 9 and the extrusion barrel 2 through the slide plate 13; during this process, the third push rod 701 and the slide bar 11 are always in conflict, and then the third push rod 701 will be separated from the slide bar 11.

[0041] When the second push rod 7 drives the plunger 8 to approach the shaping tube 18, the third push rod 701 will be displaced synchronously; after the third push rod 701 is displaced for a certain distance, it will contact the slide rod 11 again, and then drive the slide rod 11 to be displaced synchronously (the slide rod 11 slides toward the feed barrel 9 in the fixed sleeve 10), and the spring 12 will be compressed; so that the protruding column 1102 will slide with the matching groove and keep the position of the slide plate 13 unchanged, so as to maintain the blocking state of the feed barrel 9 and the extrusion barrel 2.

[0042] According to another embodiment of the present invention, the mating groove comprises a first transverse groove 1302, a first oblique groove 1303, a second transverse groove 1304 and a second oblique groove 1305; wherein the two ends of the second oblique groove 1305 are respectively connected with the first transverse groove 1302 and one end of the second transverse groove 1304; one end of the first oblique groove 1303 is connected with the other end of the second transverse groove 1304, and the other end of the first oblique groove 1303 is connected with the first transverse groove 1302; a limiting rod 1306 is rotatably installed on the slide plate 13, and a limiting column 1307 cooperating with the limiting rod 1306 is installed on the slide plate 13.

[0043] Taking the embodiment combining all the features described in the present application as an example, when in use, in the initial position, the protruding column 1102 is located at the end point of the first transverse groove 1302 close to the shaping tube 18; when the third push rod 701 gradually moves away from the fixed sleeve 10, under the elastic force of the spring 12, the connecting rod 1101 drives the protruding column 1102 away from the shaping tube 18. At this time, the protruding column 1102 will slide synchronously in the first transverse groove 1302 (the position of the sliding plate 13 remains unchanged) and slide to the first transverse groove 1302 and the first inclined groove 1303. When the connecting part is in the middle, due to the interference between the limiting rod 1306 and the limiting column 1307, the protruding column 1102 will enter the first inclined groove 1303 from the first transverse groove 1302, and slide toward the second transverse groove 1304 in the first inclined groove 1303 (at this time, under the extrusion effect of the inner wall of the first inclined groove 1303 and the protruding column 1102, the slide plate 13 will slide outward in the opening and closing groove 901, so as to drive the slot 1301 to slide synchronously, and the slot 1301 will gradually connect the feed cylinder 9 and the extrusion cylinder 2); the protruding column 1102 slides to When the first inclined groove 1303 and the second transverse groove 1304 are connected, the conductive area between the feed cylinder 9 and the extrusion cylinder 2 is the largest, and then the protruding column 1102 will enter the second transverse groove 1304 from the first inclined groove 1303 and slide toward the second inclined groove 1305 in the second transverse groove 1304 (in this process, the position of the slide plate 13 remains unchanged, and the position slot 1301 is in the position, so that the feed cylinder 9 and the extrusion cylinder 2 are always conductive); when the protruding column 1102 slides to the position of the second transverse groove 1304 and the second inclined groove 1305, the protruding column 1102 will Enter the second chute 1305, and then slide in the second chute 1305 toward the first transverse groove 1302 (under the extrusion of the inner wall of the second chute 1305 and the protruding column 1102, the slide plate 13 will slide inward in the opening and closing groove 901, thereby driving the position of the notch 1301 to change, so as to gradually reduce the conduction area between the feed cylinder 9 and the extrusion cylinder 2); when the protruding column 1102 reaches the connection between the second chute 1305 and the first transverse groove 1302, the conduction area is zero (that is, the slide plate 13 blocks the feed cylinder 9 and the extrusion cylinder 2). After that, the third push rod 701 separates from the slide bar 11, and the connecting rod 1101 contacts the fixed sleeve 10, so that the slide bar 11 stops sliding, and the protruding column 1102 is located at the connection between the second chute 1305 and the first transverse groove 1302.

[0044] When the third push rod 701 approaches the fixed sleeve 10, it will first conflict with the slide rod 11, and then drive the slide rod 11 to move synchronously, thereby driving the protruding column 1102 to slide in the first transverse groove 1302, and the sliding direction is from the connection point between the second inclined groove 1305 and the first transverse groove 1302 to the other end of the first transverse groove 1302 (in this process, the position of the slide plate 13 remains unchanged, so as to keep the feed barrel 9 and the extrusion barrel 2 in a blocked state); during the sliding process of the protruding column 1102, it will conflict with the limiting rod 1306, and drive the limiting rod 1306 to rotate and separate from the limiting column 1307, after the protruding column 1102 passes the connection point between the first inclined groove 1303 and the first transverse groove 1302. The limiting rod 1306 is separated from the protruding column 1102, and under the action of the torsion spring, the limiting rod 1306 will be reset to contact with the limiting column 1307; when the protruding column 1102 slides to the other end of the first transverse groove 1302, the distance between the plunger 8 and the shaping tube 18 is the smallest.

[0045] The extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7; and drives the cleaning mechanism and the opening and closing mechanism to act simultaneously, and drives the scraper 1704 to rotate through the cleaning mechanism to scrape off the residual polytetrafluoroethylene in the extrusion process of the previous polytetrafluoroethylene rod, so as to prevent more and more polytetrafluoroethylene from sticking to the plunger 8 during the long-term extrusion process, thereby affecting the quality of the extruded product, and effectively improving the production efficiency; and in this process, the opening and closing mechanism will first keep the position of the slide plate 13 unchanged (the slide plate 13 blocks the position of the feed cylinder 9 and the extrusion cylinder 2), and then, in the cleaning process, After the cleaning mechanism has been working for a period of time, the opening and closing mechanism drives the slide plate 13 to slide, so as to connect the feed cylinder 9 and the extrusion cylinder 2 through the slot 1301, so that the raw material can enter the extrusion cylinder 2, and after a certain amount of raw material is injected into the extrusion cylinder 2, the slide plate 13 is driven to slide in the opposite direction to seal the feed cylinder 9 and the extrusion cylinder 2; thereby, the cleaning efficiency of the cleaning mechanism can be effectively improved (preventing the newly injected raw material from sticking to the plunger 8 when the scraper 1704 scrapes off the sticky polytetrafluoroethylene during the extrusion process of the previous polytetrafluoroethylene rod), and the production efficiency and extrusion quality can be improved.

[0046] According to another embodiment of the present invention, the cleaning mechanism includes a raised column 301 installed on the hydraulic cylinder 3, and the first push rod 5 is provided with a spiral groove 501 that slides and engages with the raised column 301; a large pulley 14 is installed on the first push rod 5, a small pulley 15 is rotatably installed on the force transmission plate 6, and the large pulley 14 and the small pulley 15 are connected by a belt 16; a ratchet wheel 1501 is installed on the small pulley 15; a mating wheel 1701 is installed on the rotating rod 17, and a plurality of ratchet teeth 1702 that cooperate with the ratchet wheel 1501 are rotatably installed on the mating wheel 1701.

[0047] Taking the embodiment combining all the features recorded in the present application as an example, when in use, when the piston 4 drives the first push rod 5 to move toward the force transmission plate 6, the raised column 301 will slide and cooperate with the spiral groove 501, thereby driving the first push rod 5 to rotate, thereby driving the large pulley 14 to rotate, and driving the small pulley 15 to rotate on the force transmission plate 6 through the belt 16. When the small pulley 15 rotates, it will drive the ratchet wheel 1501 to rotate, and drive the mating wheel 1701 to rotate through the mutual interference with the ratchet tooth 1702, thereby driving the rotating rod 17 to rotate, thereby driving the scraper 1704 to rotate through the fixed block 1703, and the rotating scraper 1704 scrapes off the polytetrafluoroethylene remaining on the plunger 8.

[0048] Since the second push rod 7 will move synchronously with the third push rod 701, during the rotation of the scraper 1704, the slide rod 11 will be driven by the spring 12 to drive the protruding column 1102 to slide and cooperate with the matching groove, and the protruding column 1102 will first slide in the first transverse groove 1302 to prevent the new raw materials from entering during the scraping process of the scraper 1704 and affecting the cleaning effect.

[0049] The cleaning mechanism cleans the plunger 8, and can effectively reduce the influence of residual raw materials on the extrusion process, thereby improving production efficiency and production quality.

[0050] When the piston 4 drives the first push rod 5 to move away from the force transmission plate 6, the raised column 301 will slide and cooperate with the spiral groove 501, thereby driving the first push rod 5 to rotate, thereby driving the large pulley 14 to rotate, and driving the small pulley 15 to rotate on the force transmission plate 6 through the belt 16. When the small pulley 15 rotates, it will drive the ratchet wheel 1501 to rotate. At this time, the ratchet 1702 does not cooperate with the ratchet wheel 1501, so the rotating rod 17 does not rotate, and the scraper 1704 does not rotate either, so as to avoid the greater pressure in the extrusion barrel 2 during the extrusion process (the greater the pressure, the greater the load on the scraper 1704 to rotate) and damage the device, thereby increasing the service life of the device.

[0051] In another embodiment of the present invention, the scraper 1704 is disposed at an angle, and the scraper 1704 is in conflict with the plunger 8 .

[0052] Taking the embodiment combining all the features described in the present application as an example, when in use, the inclined scraper 1704 can improve the efficiency of scraping off polytetrafluoroethylene, and the scraper 1704 contacts the plunger 8, so as to clean the plunger 8 to the greatest extent.

[0053] In another embodiment of the present invention, the aperture of the shaping tube 18 is much smaller than the diameter of the extrusion cylinder 2, and the shaping tube 18 is relatively long.

[0054] Taking the embodiment combining all the features recorded in this application as an example, when in use, the aperture of the shaping tube 18 is smaller than the diameter of the extrusion cylinder 2, which can improve the extrusion effect and the extrusion quality; the longer shaping tube 18 can effectively shape the extruded polytetrafluoroethylene and provide solidifying time.

[0055] An extrusion process, comprising the extrusion device of the polytetrafluoroethylene rod as described above, comprising the following steps: The first step is to connect the feed barrel 9 to the raw material storage bin; connect the hydraulic cylinder 3 to the hydraulic system; start the hydraulic system; Step 2: The hydraulic system injects hydraulic liquid into the hydraulic cylinder 3 to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7. During the process of moving away, the opening and closing mechanism drives the slide plate 13 to slide outward in the opening and closing groove 901 to drive the notch 1301 to slide, thereby connecting the feed barrel 9 and the extrusion barrel 2, so that the raw material flows into the extrusion barrel 2; Step 3: The hydraulic system draws out the hydraulic liquid in the hydraulic cylinder 3 to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger 8 to approach the shaping tube 18 through the second push rod 7 to extrude the raw material in the extrusion cylinder 2 and extrude it from the shaping tube 18. The shaping tube 18 can cool and shape the polytetrafluoroethylene to form a polytetrafluoroethylene rod; Step 4: The hydraulic system will inject hydraulic liquid into the hydraulic cylinder 3 to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger 8 away from the shaping tube 18 through the second push rod 7. During the moving away process, the cleaning mechanism drives the scraper 1704 to rotate through the rotating rod 17 to clean the polytetrafluoroethylene stuck on the plunger 8, and drives the opening and closing mechanism to move again to extrude the next polytetrafluoroethylene rod.

[0056] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0057] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A polytetrafluoroethylene rod extrusion device, comprising a housing (1); and an extrusion cylinder (2) mounted on the housing (1); a shaping tube (18) being mounted on one end of the extrusion cylinder (2); It is characterized in that A plunger (8) is slidably engaged in the extrusion cylinder (2), and a second ejector rod (7) is mounted on the plunger (8); The housing (1) is provided with an extrusion mechanism, and the movement of the extrusion mechanism can drive the second push rod (7) to move closer to or farther from the shaping tube (18), thereby driving the plunger (8) to slide closer to or farther from the shaping tube (18) in the extrusion cylinder (2); A feed barrel (9) is mounted on the chassis (1); an opening and closing groove (901) is provided on the feed barrel (9); a slide plate (13) is slidably engaged on the opening and closing groove (901), and a notch (1301) is provided on the slide plate (13); The chassis (1) is provided with an opening and closing mechanism, and the movement of the extrusion mechanism can drive the movement of the opening and closing mechanism, thereby driving the slide plate (13) to slide in the opening and closing groove (901), thereby driving the notch (1301) to slide; A rotating rod (17) is rotatably mounted inside the second push rod (7), a fixed block (1703) rotatably engaged with the plunger (8) is mounted on the rotating rod (17), and a scraper (1704) is mounted on the fixed block (1703); The chassis (1) is provided with a cleaning mechanism, and the movement of the extrusion mechanism can drive the movement of the cleaning mechanism, thereby driving the rotating rod (17) to rotate, thereby driving the scraper (1704) to rotate through the fixed block (1703).

2. The extrusion device for polytetrafluoroethylene rods according to claim 1, characterized in that: The extrusion mechanism comprises a hydraulic cylinder (3) mounted on the chassis (1), a piston (4) slidably engaged in the hydraulic cylinder (3), a first push rod (5) rotatably mounted on the piston (4), and a force transmission plate (6) fixedly connected to the second push rod (7) rotatably mounted on the first push rod (5).

3. A polytetrafluoroethylene rod extrusion device according to claim 2, characterized in that: The opening and closing mechanism comprises a fixed sleeve (10) mounted on the extrusion cylinder (2), a sliding rod (11) slidably engaged in the fixed sleeve (10), a spring (12) fixedly connected to the sliding rod (11) is mounted on one side of the fixed sleeve (10) close to the force transmission plate (6), a connecting rod (1101) is mounted on the other side of the sliding rod (11), a protruding column (1102) is mounted on the connecting rod (1101), and a matching groove slidably engaged with the protruding column (1102) is provided on the sliding plate (13); a third push rod (701) capable of contacting the sliding rod (11) is mounted on the second push rod (7).

4. A polytetrafluoroethylene rod extrusion device according to claim 3, characterized in that: The matching groove comprises a first transverse groove (1302), a first oblique groove (1303), a second transverse groove (1304), and a second oblique groove (1305); wherein the two ends of the second oblique groove (1305) are respectively connected to the first transverse groove (1302) and one end of the second transverse groove (1304); one end of the first oblique groove (1303) is connected to the other end of the second transverse groove (1304), and the other end of the first oblique groove (1303) is connected to the first transverse groove (1302); a limiting rod (1306) is rotatably installed on the slide plate (13), and a limiting column (1307) that cooperates with the limiting rod (1306) is installed on the slide plate (13).

5. The extrusion device for polytetrafluoroethylene rods according to claim 3, characterized in that: The cleaning mechanism comprises a protruding column (301) mounted on the hydraulic cylinder (3); the first push rod (5) is provided with a spiral groove (501) slidably engaged with the protruding column (301); a large pulley (14) is mounted on the first push rod (5); a small pulley (15) is rotatably mounted on the force transmission plate (6); the large pulley (14) and the small pulley (15) are connected via a belt (16); a ratchet wheel (1501) is mounted on the small pulley (15); a matching wheel (1701) is mounted on the rotating rod (17); a plurality of ratchet teeth (1702) matching with the ratchet wheel (1501) are rotatably mounted on the matching wheel (1701).

6. A polytetrafluoroethylene rod extrusion device according to claim 5, characterized in that: The scraper (1704) is arranged at an angle, and the scraper (1704) is in conflict with the plunger (8).

7. The extrusion device for polytetrafluoroethylene rods according to claim 1, characterized in that: The aperture of the shaping tube (18) is much smaller than the diameter of the extrusion cylinder (2), and the shaping tube (18) is relatively long.

8. An extrusion process, comprising an extrusion device for a polytetrafluoroethylene rod as claimed in claims 1 to 7, characterized in that: The following steps are involved: The first step is to connect the feed barrel (9) to the raw material storage bin; connect the hydraulic cylinder (3) to the hydraulic system; and start the hydraulic system; Step 2: The hydraulic system injects hydraulic fluid into the hydraulic cylinder (3) to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger (8) away from the shaping tube (18) through the second push rod (7). During the moving away process, the opening and closing mechanism drives the slide plate (13) to slide outward in the opening and closing groove (901), thereby driving the notch (1301) to slide, thereby connecting the feed cylinder (9) and the extrusion cylinder (2), so that the raw material flows into the extrusion cylinder (2); Step 3: The hydraulic system draws out the hydraulic fluid in the hydraulic cylinder (3) to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger (8) to approach the shaping tube (18) through the second push rod (7) to extrude the raw material in the extrusion cylinder (2) and extrude it from the shaping tube (18). The shaping tube (18) can cool and shape the polytetrafluoroethylene to form a polytetrafluoroethylene rod. Step 4: The hydraulic system injects hydraulic fluid into the hydraulic cylinder (3) to drive the extrusion mechanism to move. The extrusion mechanism drives the plunger (8) away from the shaping tube (18) through the second push rod (7). During the moving away process, the cleaning mechanism drives the scraper (1704) to rotate through the rotating rod (17) to clean the polytetrafluoroethylene adhering to the plunger (8), and drives the opening and closing mechanism to move again to extrude the next polytetrafluoroethylene rod.

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