A laser cutting device and method for processing polytetrafluoroethylene gaskets

Abstract

The application provides a laser cutting device and method for processing polytetrafluoroethylene gaskets, and belongs to the technical field of laser cutting. The device comprises a rack, a negative pressure platform arranged in the middle of the rack, a gantry and a first displacement assembly for driving the gantry to move, a laser cutting mechanism arranged on the gantry, a supporting arm movably arranged on the rack, mounting racks arranged on the two sides of the bottom of the supporting arm, and a roller rotatably connected between the two mounting racks. A scraper is rotatably connected to the side of the mounting rack away from the roller through a torsional spring, and a stopper is arranged on the mounting rack to limit the overturning of the scraper. A supporting plate is arranged on the top of the side of the mounting rack close to the scraper, and a rotating shaft for mounting a film roll is arranged between the two supporting plates. The device replaces manual film laying work through a film covering mechanism, has higher laying efficiency, can smooth the unfolded film, reduces the probability of film wrinkles, and indirectly guarantees the cutting quality of polytetrafluoroethylene.

Description

Technical Field

[0001] This application relates to the field of laser cutting technology, specifically to a laser cutting device and method for processing polytetrafluoroethylene gaskets. Background Technology

[0002] Polytetrafluoroethylene (PTFE) gaskets are high-performance sealing elements with high-molecular-weight fluorine materials as their core base material. They possess excellent chemical stability, resistance to high and low temperatures, a low coefficient of friction, and non-stick properties. They can withstand the erosion of most corrosive media, including strong acids, strong alkalis, and organic solvents, and do not chemically react with the sealed medium. Their structure can be designed as pure PTFE gaskets, filled and modified PTFE gaskets, or expanded PTFE gaskets, depending on the application scenario. Filled and modified types can further improve compressive strength, compression resilience, and dimensional stability to meet sealing requirements under different operating conditions. In the industrial equipment field, these gaskets are commonly used for static sealing of components such as pipe flanges, valves, pressure vessels, reactors, and pump bodies, and are a key basic component in industrial sealing systems.

[0003] The processing steps for PTFE gaskets mainly include raw material cutting, pretreatment, cutting and shaping, edge treatment, and inspection. Among these, cutting and shaping is the core process that determines the dimensional accuracy and sealing performance of the gasket. Traditional processes are prone to problems such as burrs, deformation, or insufficient precision. Laser cutting equipment for PTFE gasket processing, with its characteristics of precision cutting, burr-free operation, and low thermal damage, is highly suitable for the processing requirements of this type of gasket.

[0004] Referring to Chinese patent document CN120115858B, entitled "A Laser Cutting Device and Method for Polytetrafluoroethylene Gaskets," the cutting table is located on top of the workbench; the conveyor table is located at the outer end of the workbench; the flipping mechanism includes a flipping bridge, an inclined plate, and two side seats. The side seats are fixedly mounted on the top of the workbench. The bottom end of one side of the flipping bridge is rotatably connected to one of the side seats, and the bottom end of the other side of the flipping bridge is fixedly connected to the inner side of the inclined plate. The inclined plate is tilted upwards towards the direction of the channel, and the outer side of the inclined plate is rotatably connected to the other side seat. A return spring is provided in the side seat to keep the flipping bridge in a vertical state. This document uses only a motor as a power source to both limit the movement of the PTFE raw plate and push the PTFE raw plate to the laser cutting equipment for cutting. After cutting the PTFE gasket, it can also automatically push the PTFE gasket away from the cutting table.

[0005] Regarding the aforementioned technical solutions, during laser cutting of PTFE gaskets, a negative pressure adsorption platform is required for fixation to ensure structural stability during processing. However, given the low thermal conductivity and high coefficient of thermal expansion of PTFE, the high temperatures generated during laser cutting can easily lead to thermal damage and edge deformation of the material. Therefore, a protective film needs to be applied to its surface before cutting. This protective film also serves as an auxiliary limiting function, further ensuring the dimensional accuracy of the cut. However, the current coating process relies on manual operation, which is not only inefficient but also prone to wrinkles, resulting in poor adhesion of the protective film and directly affecting the stability of the cutting quality. Summary of the Invention

[0006] In view of this, this application provides a laser cutting device and method for processing polytetrafluoroethylene gaskets, which is mainly used to solve the problems that the coating of the laser cutting device for processing polytetrafluoroethylene gaskets relies on manual operation, resulting in low processing efficiency and wrinkles that easily cause the protective film to not adhere tightly, thereby affecting the stability of cutting quality.

[0007] To address the aforementioned technical problems, this application provides a laser cutting apparatus and method for processing polytetrafluoroethylene (PTFE) gaskets, comprising a frame, a negative pressure platform disposed in the middle of the frame, a gantry frame mounted on the frame, and a first displacement component for moving the gantry frame. A laser cutting mechanism is mounted on the gantry frame. A support arm is movably mounted on the frame, and mounting frames are disposed on both sides of the bottom of the support arm. A roller is rotatably connected between the two mounting frames. A scraper is rotatably connected to the side of the mounting frame away from the roller via a torsion spring, and a mechanism for limiting the scraper's tilting is provided on the mounting frame. The frame includes a rotating stop; a support plate is provided on the top of the mounting frame near the scraper, and a rotating shaft for mounting the film roll is provided between the two support plates; a second displacement component for driving the support arm to move is provided on the frame; a driving component for driving the mounting frame to move vertically is provided on the support arm; a mounting plate is provided at one end of the frame, a second cylinder is installed in the middle of the mounting plate, a top plate is assembled at its output end, and a hot melt knife is provided on the top of the top plate; a film pressing mechanism for pressing the end of the film is movably installed at the end of the frame away from the mounting plate.

[0008] By employing the above technical solution, a film-pressing mechanism fixes the free end of the film to one side of a negative pressure platform. Then, a support arm moves the film roll along the frame, allowing the unfolded film to cover the upper surface of the PTFE substrate. During film unfolding, rollers and a scraper smooth the unfolded film, preventing wrinkles and ensuring the flatness and bonding quality of the film. After cutting, the second displacement component drives the support arm to reverse and reset, and the drive unit moves the scraper to a suitable height so that its bottom contacts the upper surface of the PTFE substrate. As the support arm moves, the scraper removes the film adhering to the PTFE substrate surface. Compared to traditional laser cutting equipment, this device replaces manual labor with a mechanized structure for film laying and peeling, resulting in higher laying efficiency and significantly reducing the probability of film wrinkles through the synergistic effect of the rollers and scraper, indirectly ensuring cutting accuracy.

[0009] Optionally, a second suction pipe is connected to the scraper, and a strip-shaped hole communicating with the second suction pipe is opened on the bottom surface of the scraper, which is used to remove air between the film and the polytetrafluoroethylene substrate during the coating process to reduce air bubbles.

[0010] By adopting the above technical solution, during the process of laying the film onto the PTFE substrate, the strip-shaped holes on the bottom of the scraper can extract the air between the film and the substrate in real time, which promotes the rapid and tight bonding of the film and the PTFE substrate, greatly reducing the residual air bubbles between them, and providing a flat processing base surface for the subsequent laser cutting of the PTFE gasket.

[0011] Optionally, a cover plate is fixedly connected to the side of the mounting frame near the roller, and the cover plate is movably sleeved on both ends of the roller; the roller has a suction hole in its circumference, and an air distribution hole communicating with the suction hole is opened in the circumference inside the roller; a cavity structure is provided below the cover plate, and a first air extraction pipe communicating with the cavity structure is connected to the cover plate.

[0012] By adopting the above technical solution, and through the cooperation of the cavity structure within the cover plate and the annular air distribution chamber inside the roller, a stable negative pressure is formed only in the suction holes in the area below the roller. During the film cutting process, this negative pressure firmly adheres to the part of the film to be cut, keeping it flat and taut, providing favorable conditions for the hot melt blade to cut. Simultaneously, the remaining film edge after cutting remains tightly attached to the outer surface of the roller under the negative pressure, effectively preventing it from scattering and ensuring the smooth operation of subsequent processes.

[0013] Optionally, the film pressing mechanism includes a horizontal plate, a connecting plate, a positioning component, and a third track; there are two positioning components, which are respectively installed on the bottom two sides of the horizontal plate; the third track is fixedly assembled on the top of the frame.

[0014] Optionally, the positioning assembly includes a fixed plate, a sleeve block, a connecting seat, a cam plate, a rocker arm, a vertical rod, a movable groove, a sliding plate, and a sliding channel. The connecting seat is fixedly mounted on the upper surface of the fixed plate, the sleeve block is fixedly mounted on the lower surface of the fixed plate, the cam plate is hinged inside the connecting seat, a movable groove is provided on one side of the cam plate, the vertical rod is vertically hinged to the cam plate and located in the movable groove, the sliding plate is movably sleeved on the top outer side of the vertical rod, the sliding channel is opened on the top of the connecting seat, the sliding plate and the sliding channel slide in cooperation, the top of the vertical rod is fixedly connected to the horizontal plate, the rocker arm is fixedly connected to one side of the cam plate, and the sleeve block slides in cooperation with the third track.

[0015] Optionally, a pressure plate is provided below the connecting plate, and a plurality of linearly arranged movable rods are fixedly connected to the upper surface of the pressure plate. The top of the movable rods penetrates through the connecting plate, and a spring is sleeved on the outside of the movable rods, with the spring located between the connecting plate and the pressure plate.

[0016] By adopting the above technical solution, the compression spring has an elastic buffering function, providing a suitable margin for the clamping action of the pressure plate. When the cam disk is rotated by the rocker arm and positioned and fixed by friction, the horizontal plate drives the connecting plate to move downward synchronously. At this time, the compression spring is compressed and generates an elastic restoring force, driving the pressure plate to smoothly press the free end of the film. This structure not only ensures the stable positioning effect of the film end, but also avoids damage to the film caused by hard pressure through the elastic buffering effect of the spring.

[0017] Optionally, the top of the top plate on the side away from the negative pressure platform is an inclined surface, and multiple air holes arranged in a linear pattern are opened on the inclined surface; multiple connecting rods are fixedly connected to the bottom of the top plate, and the bottom ends of the connecting rods penetrate the mounting plate.

[0018] By adopting the above technical solution, before the film cutting process, the air blowing holes on the inclined guide surface of the top plate can blow an upward airflow towards the film. This airflow can promote the film to adhere tightly to the outer surface of the roller, effectively increasing the contact area between the two, thereby ensuring that the negative pressure under the roller can form a stable and firm adsorption effect on the film, laying the foundation for subsequent cutting.

[0019] Optionally, a receiving box is provided on the side of the frame near the film pressing mechanism; a second motor for driving the roller to rotate is installed on the mounting frame, and the outer surface of the roller is covered with an anti-slip coating.

[0020] Optionally, the first displacement component includes a first track, a base plate, and a first motor. The base plate is fixedly connected to both sides of the bottom of the gantry frame, the first motor is mounted on the base plate, and the first track is set on the frame. The second displacement component includes a second track and a third motor. The second track is set on the frame, and the third motor is mounted on the support arm. The driving component includes a first cylinder and a guide rod. The first cylinder is fixedly mounted on the top of the support arm, and its output shaft is connected to the mounting frame. The bottom of the guide rod passes through the support arm and is fixedly connected to the mounting frame.

[0021] A method for laser cutting polytetrafluoroethylene gaskets includes the following steps:

[0022] S1. Place the polytetrafluoroethylene sheet on the negative pressure platform, put the film roll on the rotating shaft, pull the free end of the film around the bottom of the roller, and pass it under the pressure plate.

[0023] S2. Move the rocker arm upward to lock the positioning assembly in place, and press the pressure plate downward to press the end of the film. The second displacement assembly drives the support arm to move towards the PTFE plate. At this time, the roller and scraper guide the film to unfold and cover the upper surface of the PTFE plate. At the same time, air is extracted through the strip hole to reduce air bubbles between the film and the PTFE plate.

[0024] S3. After the support arm moves past the hot melt blade, the hot melt blade rises to cut the film. During this process, the suction hole at the bottom of the roller draws air to adsorb the film, assisting in cutting and preventing the film from scattering.

[0025] S4. The negative pressure platform is activated to adsorb and fix the film and the polytetrafluoroethylene (PTFE) substrate; the laser cutting mechanism cuts the PTFE substrate.

[0026] S5. After cutting, turn off the negative pressure platform and adjust the height of the mounting bracket through the drive component so that the scraper contacts the surface of the PTFE original plate; then the second displacement component drives the support arm to move in the opposite direction, using the scraper to scrape off the film and let it fall into the receiving box; remove the cut PTFE gasket.

[0027] By adopting the above technical solution, the laser cutting method for polytetrafluoroethylene gaskets automates the entire process of film laying, precise cutting, waste film peeling and centralized collection through mechanized collaborative operation. This significantly reduces manual intervention, improves processing efficiency and reduces labor intensity. Furthermore, the combined use of roller guidance, scraper smoothing and strip hole air extraction reduces film bubbles and wrinkles, ensuring continuous and smooth processing and stable product quality throughout the process.

[0028] In summary, compared with the prior art, this application includes at least one of the following beneficial technical effects:

[0029] 1. The film laying operation is completed by replacing manual labor with a film coating mechanism, which not only improves the laying efficiency, but also smooths the unfolded film, reduces the probability of film wrinkles, and indirectly ensures the cutting quality of PTFE. At the same time, the film peeling process after cutting is carried out simultaneously with the support arm resetting action, without the need for additional manual operation. This allows workers to quickly remove the cut PTFE gaskets, significantly improving the overall processing efficiency and effectively reducing the labor intensity of operators.

[0030] 2. By setting an air extraction structure at the bottom of the scraper, the air between the film and the PTFE base plate is extracted in real time during the coating process, which promotes the rapid bonding of the two, thereby reducing the residual air bubbles and providing a flat processing base for subsequent laser cutting, effectively ensuring the cutting accuracy of the PTFE gasket.

[0031] 3. Through the cooperation between the roller, suction hole, cover plate, air distribution hole and cavity structure, a stable negative pressure can be formed in the area below the roller. During film cutting, the part of the film to be cut can be kept flat and taut, providing favorable conditions for the hot melt knife to cut accurately. At the same time, it can adsorb and fix the remaining film after cutting, preventing it from scattering. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of a laser cutting device for processing polytetrafluoroethylene gaskets according to this application;

[0033] Figure 2 This is a three-dimensional structural diagram of the coating mechanism in this application;

[0034] Figure 3 This is a schematic diagram of the right-side structure of the pressure membrane mechanism in this application;

[0035] Figure 4 This is a schematic diagram of the right-side structure of the interrupted membrane assembly of this application;

[0036] Figure 5 This is a front view structural diagram of the top plate and hot melt knife in this application;

[0037] Figure 6 This is a front view schematic diagram of the coating mechanism in this application;

[0038] Figure 7 This is a schematic cross-sectional view of the roller and scraper in this application;

[0039] Figure 8 This is a cross-sectional structural diagram of the roller and cover plate in this application;

[0040] Figure 9 This is a schematic diagram of the internal structure of the connector in this application;

[0041] Figure 10This is a rear view diagram of the structure when the connector is fixed in this application;

[0042] Figure 11 This is a cross-sectional structural diagram of the connecting seat when it is fixed in this application;

[0043] Figure 12 This is a schematic diagram of the film peeling state during the resetting process of the film coating mechanism in this application.

[0044] Explanation of reference numerals in the attached drawings: 1. Frame; 11. First track; 12. Second track; 13. Negative pressure platform; 14. Container box; 15. Third track; 2. Gantry frame; 21. Base plate; 22. First motor; 3. Laser cutting mechanism; 4. Support arm; 41. Mounting frame; 411. First cylinder; 412. Guide rod; 42. Roller; 421. Suction hole; 422. First extraction pipe; 423. Cover plate; 424. Air distribution hole; 43. Scraper; 431. Stop block; 432. Second extraction pipe; 433. 44. Strip hole; 44. Support plate; 441. Rotating shaft; 45. Second motor; 46. Third motor; 5. Horizontal plate; 51. Fixing plate; 511. Sleeve block; 512. Connecting seat; 513. Cam plate; 514. Rocker arm; 515. Vertical rod; 516. Movable groove; 517. Slide plate; 518. Slide groove; 52. Connecting plate; 521. Pressure plate; 522. Movable rod; 523. Spring; 6. Mounting plate; 61. Top plate; 611. Air blowing hole; 612. Hot melt knife; 62. Connecting rod; 63. Second cylinder. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will be combined with the embodiments of this application. Figures 1-12 The technical solutions of the embodiments of this application are clearly and completely described herein. All other embodiments obtained by those skilled in the art based on the described embodiments are within the scope of protection of this application.

[0046] Firstly, referring to Figure 1 , Figure 2 , Figure 3 and Figure 4This embodiment provides a laser cutting device for processing polytetrafluoroethylene (PTFE) gaskets, including a body, a laser cutting mechanism 3, a film pressing mechanism, a film coating mechanism, and a film cutting assembly. The body, as the main load-bearing structure of the device, includes a frame 1, a negative pressure platform 13, a gantry 2, and two sets of symmetrically arranged first displacement components. The frame 1 serves as the core mounting base, providing stable assembly support for each functional mechanism and component. The negative pressure platform 13 is located in the middle of the frame 1 and is used to support the PTFE raw sheet to be processed. The two sets of first displacement components are symmetrically assembled on the frame 1 and are used to drive the gantry 2 to translate along the length of the frame 1. The gantry 2 is slidably fitted to the frame 1 and serves as the mounting carrier for the laser cutting mechanism 3. The film pressing mechanism is assembled at one end of the frame 1 and is used to press the free end of the film. The film coating mechanism is used to carry the film roll and drive it to unfold smoothly, so that the film flatly covers the upper surface of the PTFE raw sheet. The film cutting assembly is located at the other end of the frame 1 away from the film pressing mechanism and is used to precisely cut the film after coating. It should be noted that the negative pressure platform 13 and the laser cutting mechanism 3 in this embodiment both adopt conventional and mature technologies in the field, and their specific structures and working principles are within the scope of existing technologies, and will not be described in detail here.

[0047] Among them, reference Figure 1 The first displacement component includes a first track 11, a base plate 21, and a first motor 22. The base plate 21 is symmetrically fixedly connected to the bottom two sides of the gantry frame 2, and its bottom is slidably engaged with the first track 11. The first motor 22 is fixedly mounted on the base plate 21, and a gear is fixedly provided at the end of its output shaft. The first track 11 is fixedly installed on the frame 1, and a rack that meshes with the gear is provided on the side of the first track 11.

[0048] After the first motor 22 starts, its output shaft drives the gear to rotate. Through the meshing transmission between the gear and the rack on the first track 11, the gantry 2 is driven to move along the length of the frame 1, thereby adjusting the processing position of the laser cutting mechanism 3.

[0049] Among them, reference Figure 1 , Figure 3 , Figure 9 , Figure 10 and Figure 11 The film pressing mechanism includes a horizontal plate 5, a connecting plate 52, two sets of positioning components, and two sets of third tracks 15. The two sets of positioning components are symmetrically assembled on both sides of the bottom of the horizontal plate 5 to provide movement and positioning support for the film pressing mechanism; the two sets of third tracks 15 are symmetrically fixed to the top of the frame 1 along the length of the frame 1.

[0050] The positioning assembly includes a fixed plate 51, a sleeve block 511, a connecting seat 512, a cam plate 513, a rocker arm 514, a vertical rod 515, a movable groove 516, a sliding plate 517, and a sliding channel 518. The connecting seat 512 is fixedly mounted on the upper surface of the fixed plate 51, and the sleeve block 511 is fixedly mounted on the lower surface of the fixed plate 51, adapting to slide with the third track 15. The cam plate 513 is hinged in the internal cavity of the connecting seat 512, and a movable groove 516 is provided on one side of the cam plate 513. The vertical rod 515 is vertically hinged to the cam plate 513 and positioned accordingly. Within the movable groove 516, the movable groove 516 provides space for the movement of the vertical rod 515; the sliding plate 517 is slidably sleeved on the top outer side of the vertical rod 515, and the sliding groove 518 is opened horizontally on the top end face of the connecting seat 512. The sliding plate 517 and the sliding groove 518 slide in cooperation, which can radially limit the vertical rod 515 to ensure that it always remains vertical; the top of the vertical rod 515 is fixedly connected to the horizontal plate 5, and the rocker arm 514 is fixedly connected to one side of the cam disk 513, serving as the operating end for driving the cam disk 513 to rotate around the hinge axis.

[0051] When the rocker arm 514 is in a horizontal position, a small gap is maintained between the bottom of the cam disk 513 and the upper surface of the frame 1. At this time, the entire film pressing mechanism can move smoothly along the third track 15. After the film pressing mechanism moves to the preset position, the rocker arm 514 is pulled upward. The rocker arm 514 drives the cam disk 513 to rotate around the hinge point between it and the connecting seat 512 until the outer edge protrusion of the cam disk 513 is tightly attached to the upper surface of the frame 1. The friction between the two is used to lock and fix it, and the rocker arm 514 maintains its current posture and no longer rotates. At the same time, during the rotation of the cam disk 513, it synchronously drives the vertical rod 515 to slide along the slide groove 518 and move downward. The vertical rod 515 drives the horizontal plate 5 to move downward synchronously, thereby causing the connecting plate 52 to press and fix the free end of the film.

[0052] Among them, reference Figure 1 , Figure 2 , Figure 6 , Figure 7 and Figure 12The film coating mechanism includes a support arm 4, a mounting frame 41, a roller 42, a scraper 43, a stop block 431, a support plate 44, a rotating shaft 441, a second displacement assembly, and a drive component. The support arm 4 has a U-shaped structure, and there are two sets of mounting frames 41, the second displacement assembly, and the drive component. The two sets of mounting frames 41 are symmetrically fixed on both sides of the bottom of the support arm 4. The roller 42 is horizontally rotatably connected between the two mounting frames 41 via bearings, forming a film guiding and conveying structure. The scraper 43 is rotatably mounted between the two mounting frames 41 via a torsion spring. The stop block 431 is fixedly connected to the side of the mounting frame 41 away from the roller 42 to limit the scraper 43 from excessively rotating in the direction away from the roller 42. There are two support plates 44, which are symmetrically fixed to the top of the two sets of mounting frames 41 on the side near the scraper 43, and their tops are made of... The U-shaped opening structure facilitates the quick loading, unloading, and replacement of the rotating shaft 441. The film roll is fitted on the outside of the rotating shaft 441, with its free end passing between the roller 42 and the scraper 43, around the bottom of the roller 42, and extending towards the pressing mechanism. Two sets of second displacement components are symmetrically arranged on the frame 1 to drive the support arm 4 to move along the length of the frame 1, thereby achieving synchronous unfolding of the film roll. Two sets of drive components are correspondingly assembled on the support arm 4 to drive the mounting frame 41 to rise and fall vertically, adapting to polytetrafluoroethylene sheets of different thicknesses.

[0053] Specifically, the second displacement component includes a second track 12 and a third motor 46. The second track 12 is fixedly mounted on the frame 1 along the length direction of the frame 1. The third motor 46 is fixedly mounted on the side of the support arm 4, and a gear is fixedly mounted on the output shaft end. A rack that meshes with the gear is provided on the side of the second track 12. After the third motor 46 is started, it drives the support arm 4 to move smoothly along the length direction of the frame 1 through the meshing transmission of the gear and the rack, so as to realize the uniform unfolding of the film.

[0054] Specifically, the driving component includes a first cylinder 411 and a guide rod 412. The cylinder body of the first cylinder 411 is fixedly mounted on the top of the support arm 4, and its output shaft extends vertically downward and is fixedly connected to the top of the mounting frame 41. The guide rod 412 is arranged in a vertical direction, its bottom passes through the support arm 4 and is fixedly connected to the mounting frame 41. The guide rod 412 is slidably engaged with the support arm 4 to guide and limit the vertical movement of the mounting frame 41, effectively improving the stability and smoothness of the lifting process of the mounting frame 41.

[0055] After the free end of the film is pressed by the film pressing mechanism, the second displacement component drives the support arm 4 to move along the length of the frame 1. At this time, the film roll unfolds synchronously under the action of the tensile force. During its movement, the bottom of the scraper 43 is slightly flipped towards the roller 42 by the extrusion force of the polytetrafluoroethylene plate and squeezes the torsion spring, so that a suitable small gap is formed between the scraper 43 and the roller 42. This gap can limit and guide the passing film, effectively preventing the film from wrinkling. At the same time, the scraper 43, together with the spreading action of the roller 42, further smooths the film, improving the flatness and bonding quality of the coating.

[0056] After the coating operation is completed, the drive unit drives the mounting frame 41, along with the roller 42 and scraper 43, to move upward as a whole. The scraper 43 is reset under the elastic restoring force of the torsion spring. Then, the drive unit adjusts the vertical height of the mounting frame 41 so that the bottom of the scraper 43 is in close contact with the upper surface of the PTFE substrate. Immediately afterwards, the second displacement component drives the support arm 4 to move in the opposite direction along the length of the frame 1 and reset. As the scraper 43 moves with the support arm 4, the film attached to the surface of the PTFE substrate can be peeled off and scraped off simultaneously without the need for manual secondary cleaning, which greatly simplifies the operation process and improves the ease of use.

[0057] Among them, reference Figure 4 and Figure 5 The film cutting assembly includes a mounting plate 6, a top plate 61, connecting rods 62, a hot melt blade 612, and a second cylinder 63. The mounting plate 6 is fixedly connected to the end of the frame 1 away from the film pressing mechanism. The top plate 61 is positioned above the mounting plate 6, and its bottom is connected to the output end of the second cylinder 63. The second cylinder 63 is fixedly mounted vertically in the middle of the mounting plate 6, and its output shaft extends vertically upward and is fixedly connected to the bottom of the top plate 61, providing power for the lifting and lowering of the top plate 61. There are multiple connecting rods 62, which are arranged linearly at the bottom of the top plate 61. The bottom end of the connecting rod 62 passes through the mounting plate 6, guiding the top plate 61 to make its movement more stable. The hot melt blade 612 is fixedly mounted on the top of the top plate 61, with its blade facing the film cutting station and adapted to the film laying path.

[0058] After the film is laid, the second cylinder 63 is started, and its output shaft drives the top plate 61 to move vertically upward. The hot melt knife 612 rises synchronously with the top plate 61 and precisely cuts the film. After the film is cut, the negative pressure platform 13 is started, and the film is tightly fixed to the polytetrafluoroethylene plate through negative pressure adsorption.

[0059] Additionally, refer to Figure 7A second suction pipe 432 is connected to the scraper 43, and a strip-shaped hole 433 communicating with the second suction pipe 432 is opened on the bottom surface of the scraper 43. In this embodiment, the end of the second suction pipe 432 away from the scraper 43 is connected to an external negative pressure suction device to remove air between the film and the polytetrafluoroethylene substrate during the lamination process, thereby reducing air bubble residue.

[0060] During the lamination process, if air between the film and the PTFE substrate is not expelled in time, air bubbles can easily form. These air bubbles can cause the film and substrate to not adhere tightly, thus affecting the accuracy of subsequent laser cutting. Therefore, through the coordinated action of the second air extraction pipe 432 and the external air extraction equipment, the strip-shaped hole 433 on the bottom surface of the scraper 43 can extract the air between the film and the PTFE substrate in real time during the lamination process, promoting rapid and tight adhesion between the two, significantly reducing the amount of residual air bubbles, providing a flat processing base surface for the subsequent laser cutting process, and thus ensuring the cutting quality of the PTFE gasket.

[0061] Reference Figure 7 and Figure 8 A cover plate 423 is fixedly connected to the side of the mounting frame 41 near the roller 42, and the cover plate 423 is movably sleeved on both ends of the roller 42. The roller 42 has a suction hole 421 circumferentially arranged, and an air distribution hole 424 communicating with the suction hole 421 is circumferentially arranged inside the roller 42. A cavity structure is provided below the cover plate 423, and a first suction pipe 422 communicating with the cavity structure is connected to the cover plate 423. In this embodiment, the first suction pipe 422 is connected to an external negative pressure suction device.

[0062] The roller 42 is constantly rotating during the coating process, while the film cutting process only requires negative pressure in the bottom area of ​​the roller 42 to meet the operational requirements. Therefore, through the matching and cooperation of the cavity structure inside the cover plate 423 and the annular air distribution hole 424 inside the roller 42, a stable negative pressure can be formed only at the air suction hole 421 in the area below the roller 42. In the film cutting process, this stable negative pressure can firmly adsorb the part of the film to be cut, keeping it in a flat and taut state, providing favorable conditions for the cutting by the hot melt knife 612; at the same time, the remaining film after cutting can continue to stick tightly to the outer surface of the roller 42 under the adsorption of negative pressure, effectively preventing it from scattering randomly, thereby ensuring the smooth progress of subsequent processes.

[0063] Reference Figure 3 A pressure plate 521 is provided below the connecting plate 52. Multiple movable rods 522 arranged linearly are fixedly connected to the upper surface of the pressure plate 521. The top of the movable rods 522 passes through the connecting plate 52. A spring 523 is sleeved on the outside of the movable rods 522. The spring 523 is located between the connecting plate 52 and the pressure plate 521.

[0064] Spring 523 possesses elastic buffering characteristics, providing a suitable buffer margin for the pressing action of pressure plate 521. When the cam disk 513 is driven to rotate by rocker arm 514, and positioning and locking are achieved by the friction between cam disk 513 and frame 1, the horizontal plate 5 drives the connecting plate 52 to move downward synchronously. At this time, spring 523 is compressed and generates elastic restoring force, driving pressure plate 521 to smoothly press the free end of the film. This structure not only ensures the stable positioning effect of the free end of the film, but also avoids the squeezing damage to the film caused by hard pressure through the elastic buffering effect of spring 523.

[0065] Among them, reference Figure 4 and Figure 5 The top of the top plate 61, on the side away from the negative pressure platform 13, is an inclined surface. Multiple air-blowing holes 611 are evenly distributed along a linear direction on this inclined surface. These air-blowing holes 611 are connected to external air-blowing equipment via air supply pipes. Before the film cutting process, the air-blowing holes 611 blow upward-sloping airflow towards the film. This airflow promotes close contact between the film and the outer surface of the roller 42, effectively increasing the contact area between them. This ensures that the negative pressure below the roller 42 can form a stable and firm adsorption effect on the film, laying the foundation for subsequent precise cutting.

[0066] Reference Figure 1 and Figure 6 A receiving box 14 is provided on the side of the frame 1 near the film pressing mechanism. A second motor 45 for driving the rotation of the roller 42 is installed on the mounting frame 41. The outer surface of the roller 42 is covered with an anti-slip coating. The output end of the second motor 45 is connected to the roller 42 through a belt drive mechanism to achieve stable power transmission. The receiving box 14 is used to collect the waste film after peeling, which not only prevents the waste film from scattering and polluting the working environment, but also facilitates the subsequent unified disposal by the staff. During the film coating process, the second motor 45 drives the roller 42 to rotate synchronously, providing active conveying power for the film to unfold, effectively avoiding tearing or breakage of the film due to uneven force or excessive tension during unfolding, and ensuring the continuous and smooth operation of the film coating process.

[0067] The implementation principle of a laser cutting device for processing polytetrafluoroethylene gaskets according to an embodiment of this application is as follows:

[0068] Initial preparation and positioning: First, place the PTFE sheet to be processed on the negative pressure platform 13. Wrap the film roll around the outside of the rotating shaft 441, pulling the free end of the film around the bottom of the roller 42 and between the scraper 43, extending it to below the pressure plate 521 of the film pressing mechanism. Operate the rocker arm 514 to move it upwards from a horizontal position, driving the cam disk 513 to rotate around the hinge point until the protrusion of the cam disk 513 is tightly fitted against the upper surface of the frame 1. The film pressing mechanism is locked and positioned through friction. Simultaneously, the cam disk 513 drives the vertical rod 515 downwards, and the horizontal plate 5 and connecting plate 52 sink synchronously. Under the elastic buffering action of the spring 523, the pressure plate 521 smoothly presses the free end of the film, preventing damage to the film due to pressure.

[0069] Automated lamination operation: The third motor 46 is started, and through the meshing of gears and racks on the second track 12, it drives the support arm 4 to move horizontally along the length of the frame 1 towards the negative pressure platform 13. At the same time, the second motor 45 drives the roller 42 to rotate through the belt drive mechanism (the anti-slip coating on the outer surface of the roller 42 enhances friction), providing active conveying power for film unfolding and avoiding uneven force or tearing of the film. During the lamination process, the scraper 43 squeezes the torsion spring and rotates slightly under the pressure of the PTFE plate, forming a small gap with the roller 42, limiting and guiding the film and smoothing it in conjunction with the roller 42. At the same time, the external negative pressure air extraction equipment is connected to the strip hole 433 on the bottom surface of the scraper 43 through the second air extraction pipe 432, extracting air between the film and the PTFE plate in real time, reducing air bubble residue, and ensuring that the film is flat and tightly adhered to the plate.

[0070] Precise film cutting and fixed state: After the support arm 4 moves to the preset film-covering endpoint (passing over the film cutting component), the second cylinder 63 is activated, driving the top plate 61 to move smoothly upward along the connecting rod 62. The hot melt blade 612 on the top plate 61 rises synchronously to cut the film. Before film cutting, the air blowing holes 611 on the inclined surface of the top plate 61 blow out an upward airflow through the external air blowing device, causing the film to adhere tightly to the outer surface of the roller 42, increasing the contact area. At the same time, the external negative pressure suction device is connected to the annular air distribution hole 424 inside the roller 42 through the cavity structure of the first suction pipe 422 and the cover plate 423, forming a stable negative pressure only in the area below the roller 42. This suction adsorbs the part of the film to be cut, keeping it taut and flat, ensuring the accuracy of film cutting. The remaining end of the cut film is continuously adsorbed by the negative pressure on the surface of the roller 42, preventing it from scattering. After film cutting is completed, the negative pressure platform 13 is activated, and the PTFE plate and the covering film are firmly fixed by the negative pressure adsorption, providing a stable base surface for cutting.

[0071] Laser cutting and position adjustment: The first motor 22 of the first displacement component is started, and its output shaft drives the gear to rotate. Through the meshing transmission between the gear and the rack on the first track 11, the gantry 2 is driven to move along the length direction of the frame 1, thereby adjusting the processing position of the laser cutting mechanism 3 on the gantry 2 to achieve precise cutting of the polytetrafluoroethylene plate (the laser cutting mechanism 3 completes the gasket forming process according to the preset path).

[0072] Waste film peeling and centralized collection: After cutting, the adsorption function of the negative pressure platform 13 is turned off, the first cylinder 411 is activated, driving the mounting frame 41, roller 42 and scraper 43 to move upward as a whole. The scraper 43 is reset under the elastic restoring force of the torsion spring. Then the first cylinder 411 is activated again to adjust the vertical height of the mounting frame 41 so that the bottom of the scraper 43 is in contact with the upper surface of the PTFE original plate. The second displacement component is activated to drive the support arm 4 to move in the opposite direction along the frame 1 and reset. As the scraper 43 moves with the support arm 4, it simultaneously peels off the waste film attached to the surface of the original plate. The peeled waste film falls into the receiving box 14 under the guidance of the scraper 43 for centralized collection. Finally, the cut PTFE gasket is removed, completing a single processing cycle.

[0073] In a second aspect, a laser cutting method for polytetrafluoroethylene (PTFE) gaskets is applied to the laser cutting apparatus for processing PTFE gaskets as described in the first aspect, the cutting method comprising:

[0074] S1. Place the polytetrafluoroethylene (PTFE) base plate on the negative pressure platform 13, put the film roll on the rotating shaft 441, and pull the free end of the film around the bottom of the roller 42 and through the bottom of the pressure plate 521.

[0075] S2. Move the rocker arm 514 upward to lock the positioning component in place, and press the pressure plate 521 downward to press the end of the film. The second displacement component drives the support arm 4 to move towards the polytetrafluoroethylene base plate. At this time, the roller 42 and the scraper 43 guide the film to unfold and cover the upper surface of the polytetrafluoroethylene base plate. At the same time, the air is extracted through the strip hole 433 to reduce the air bubbles between the film and the polytetrafluoroethylene base plate.

[0076] S3. When the support arm 4 moves past the hot melt blade 612, the hot melt blade 612 rises to cut the film. During this process, the suction hole 421 at the bottom of the roller 42 draws air to adsorb the film, assisting in cutting and preventing the film from scattering.

[0077] S4. The negative pressure platform 13 is activated to adsorb and fix the film and the polytetrafluoroethylene (PTFE) plate; the laser cutting mechanism 3 cuts the PTFE plate.

[0078] S5. After cutting, close the negative pressure platform 13, adjust the height of the mounting bracket 41 through the drive component, so that the scraper 43 contacts the surface of the polytetrafluoroethylene original plate; then the second displacement component drives the support arm 4 to move in the opposite direction, and scrapes off the film with the scraper 43 and makes it fall into the receiving box 14; remove the cut polytetrafluoroethylene gasket.

[0079] The above description is the preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principles described in this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A laser cutting device for processing polytetrafluoroethylene gasket, comprising a rack, a negative pressure platform is arranged in the middle of the rack, a gantry and a first displacement assembly for driving the gantry to move are arranged on the rack, and a laser cutting mechanism is arranged on the gantry, characterized in that: a supporting arm is movably arranged on the rack, mounting racks are arranged on the bottom of the supporting arm, a roller is rotatably connected between the two mounting racks, a scraper is rotatably connected to the side of the mounting rack away from the roller through a torsional spring, a stopper is arranged on the mounting rack to limit the turning of the scraper, supporting plates are arranged on the side of the mounting rack close to the scraper, and a rotating shaft for mounting a film roll is arranged between the two supporting plates; a second displacement assembly for driving the supporting arm to move is arranged on the rack; and a driving piece for driving the mounting rack to move vertically is arranged on the supporting arm; an installation plate is arranged at one end of the rack, a second cylinder is arranged in the middle of the installation plate, a top plate is assembled at the output end of the second cylinder, and a hot melting knife is arranged on the top of the top plate; and a film pressing mechanism for pressing the end of the film is movably arranged at the end of the rack away from the installation plate; the scraper is connected with a second air suction pipe, and strip-shaped holes are arranged on the bottom surface of the scraper and communicated with the second air suction pipe; a cover plate is fixedly connected to the side of the mounting rack close to the roller, and the cover plate is movably sleeved on both ends of the roller; air suction holes are arranged in the circumferential direction of the roller, and air distribution holes are arranged in the circumferential direction of the inner part of the roller and communicated with the air suction holes; a cavity structure is arranged below the cover plate, and a first air suction pipe is connected with the cavity structure and communicated therewith; the film pressing mechanism comprises a horizontal plate, a connecting plate, a positioning assembly and a third track; the positioning assembly comprises two positioning assemblies, and the two positioning assemblies are arranged on the bottom of the horizontal plate; and the third track is fixedly assembled on the top of the rack; the positioning assembly comprises a fixed plate, a sleeve block, a connecting seat, a cam disc, a rocker, a vertical rod, a movable slot, a sliding plate and a sliding groove; the connecting seat is fixedly assembled on the upper surface of the fixed plate, the sleeve block is fixedly assembled on the lower surface of the fixed plate, the cam disc is hingedly connected in the connecting seat, the movable slot is arranged on one side of the cam disc, the vertical rod is vertically hingedly connected to the cam disc and located in the movable slot, the sliding plate is movably sleeved on the top of the vertical rod, the sliding groove is arranged on the top of the connecting seat, the sliding plate is slidably connected with the sliding groove, the top end of the vertical rod is fixedly connected with the horizontal plate, the rocker is fixedly connected on one side of the cam disc, and the sleeve block is slidably connected with the third track.

2. The laser cutting device for processing polytetrafluoroethylene gaskets according to claim 1, characterized in that: a pressing plate is arranged below the connecting plate, a plurality of linearly arranged movable rods are fixedly connected to the upper surface of the pressing plate, the top end of the movable rod penetrates through the connecting plate, a spring is sleeved on the outside of the movable rod, and the spring is located between the connecting plate and the pressing plate.

3. A laser cutting device for processing polytetrafluoroethylene gaskets according to claim 2, characterized in that: the top of the side of the top plate away from the negative pressure platform is an inclined surface, a plurality of linearly arranged air blowing holes are arranged on the inclined surface; a plurality of connecting rods are fixedly connected to the bottom of the top plate, and the bottom end of the connecting rod penetrates through the installation plate.

4. The laser cutting device for machining polytetrafluoroethylene gaskets according to claim 3, characterized in that: a containing box is arranged on the side of the rack close to the film pressing mechanism; a second motor for driving the roller to rotate is arranged on the mounting rack, and an anti-skid coating is arranged on the outer surface of the roller.

5. The laser cutting device for machining of polytetrafluoroethylene gaskets according to claim 1, characterized in that: The first displacement assembly comprises a first track, a bottom plate and a first motor, the bottom plate is fixedly connected to the bottom of the gantry, the first motor is assembled on the bottom plate, and the first track is arranged on the rack; the second displacement assembly comprises a second track and a third motor, the second track is arranged on the rack, and the third motor is assembled on the support arm; The driving member comprises a first cylinder and a guide rod, the first cylinder is fixedly assembled at the top of the support arm, the output shaft of the first cylinder is connected with the mounting frame, and the bottom of the guide rod penetrates through the support arm and is fixedly connected with the mounting frame.

6. A laser cutting method of a polytetrafluoroethylene gasket based on the laser cutting apparatus for processing a polytetrafluoroethylene gasket according to claim 4, characterized by, The method comprises the following steps: S1, place the polytetrafluoroethylene original plate on the negative pressure platform, wrap the film roll on the shaft, pull the free end of the film around the bottom of the roller, and pass through the lower part of the pressing plate; S2, pull up the rocker to lock and fix the positioning assembly, and press the pressing plate to the lower part of the film; the second displacement assembly drives the support arm to move towards the direction of the polytetrafluoroethylene original plate, at this time the roller cooperates with the scraper to guide the film to be unfolded and covered on the upper surface of the polytetrafluoroethylene original plate, and the strip-shaped hole is used to suck air to reduce the air bubbles between the film and the polytetrafluoroethylene original plate; S3, when the support arm moves over the hot melting knife, the hot melting knife rises to cut the film, in this process, the air suction hole at the bottom of the roller sucks the film to assist cutting and prevent the film from scattering; S4, start the negative pressure platform to adsorb and fix the film and the polytetrafluoroethylene original plate; the laser cutting mechanism cuts the polytetrafluoroethylene original plate; S5, after cutting, turn off the negative pressure platform, adjust the height of the mounting frame through the driving member, so that the scraper contacts the surface of the polytetrafluoroethylene original plate; then the second displacement assembly drives the support arm to move reversely, the scraper is used to scrape off the film and make it fall into the containing box; remove the cut polytetrafluoroethylene gasket.

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