Artificial turf grass fiber drawing, drafting and setting device

Abstract

This invention relates to the field of artificial turf fiber forming equipment, specifically to an artificial turf fiber drawing, stretching, and shaping device, comprising a heat-setting air box. The heat-setting air box contains a heat treatment channel for the continuous passage of long filaments. The heat-setting air box includes a box body, a filament-passing gantry, an upper air cushion flow stabilizer plate, a lower air cushion flow stabilizer plate, an upper air inlet diverter block, and a lower air inlet diverter block. The filament-passing gantry is vertically fixed to the bottom wall of the box body. This invention uses a non-contact hot air cushion support to replace the traditional mechanical limiting structure. This achieves stable constraint on the movement trajectory of the filaments, avoiding surface roughening, scratching, and filament breakage caused by mechanical contact during high-speed operation. It also eliminates the need to reduce the hot air circulation speed, ensuring heat-setting efficiency and sufficient crystallization. Furthermore, it eliminates the need to extend the axial length of the heat-setting air box, reducing equipment footprint and energy consumption, and adapting to the needs of high-capacity continuous production.

Description

Technical Field

[0001] This invention relates to the field of artificial turf fiber forming equipment, specifically to an artificial turf fiber drawing, stretching, and shaping device. Background Technology

[0002] Currently, mainstream artificial turf filament drawing, stretching, and setting devices generally employ continuous production lines consisting of a pre-stage stretching roller assembly, a heat-setting air box, and a post-stage tension guiding mechanism. Polyethylene or polypropylene, after initial stretching, passes through the heat-setting air box in a flat state. While maintaining axial tension, high-temperature hot air eliminates tensile stress and fixes the crystalline form. The heat-setting air box, as the core heat transfer component, typically contains a fan, heating elements, and a threading cavity for the filaments to pass through. However, under high-capacity drawing conditions, to ensure that the highly elastic polymer filaments reach the crystallization temperature within a limited axial stroke, the hot air circulation velocity within the threading cavity must be significantly increased. When a strong circulating airflow washes over the surface of a slender monofilament at high speed, it can easily induce violent fluid-induced self-excited vibrations, causing the array of filaments to swing violently laterally and become axially unstable. This can lead to mutual scraping between filaments, entanglement across grooves, and high-frequency filament breakage. At the same time, non-uniform pressure gradients and local turbulent vortices are easily formed at the inlet and outlet of the threading cavity and on the wall boundary layer. This results in deviations in the convective heat transfer coefficients of filaments at different cross-sectional positions, leading to poor consistency in the physical and mechanical properties of the finished filament, such as crystallinity, thermal shrinkage rate, and elongation at break.

[0003] To address the aforementioned issues, existing technologies offer several solutions. For example, densely installing multi-groove combing plates or mechanical pressure rollers along the straw fiber transport path inside the heat-setting air box attempts to physically constrain the straw fiber's movement trajectory. However, the combing plates or pressure rollers, operating at high speeds, engage in rigid sliding contact with the highly elastic straw fibers, easily causing surface roughening, scratches, or even breakage. Furthermore, the mechanical limiting components readily accumulate polymer debris, significantly increasing maintenance frequency. Another approach involves reducing fan speed to minimize airflow disturbance or drastically extending the axial length of the air box. While this method alleviates straw fiber vibration, reducing airflow speed leads to a sharp drop in heat transfer efficiency and insufficient straw fiber setting, resulting in severe shrinkage deformation during subsequent winding or use. Extending the air box significantly increases equipment footprint and energy consumption, reducing the overall efficiency of the production line.

[0004] Therefore, there is a need for an artificial turf fiber drawing, stretching and shaping device that can eliminate the disturbance and instability of the grass fibers caused by high-speed airflow and friction damage while ensuring high-efficiency hot air circulation and compact box structure, so as to adapt to the continuous production of artificial turf fibers with high capacity and high quality. Summary of the Invention

[0005] The purpose of this invention is to provide an artificial turf grass fiber pulling, stretching and shaping device to solve the problems mentioned in the background art, such as the easy damage to grass fibers caused by existing mechanical limiting schemes and the insufficient heat shaping efficiency of wind speed reduction schemes.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A device for drawing, stretching, and shaping artificial turf fibers includes a heat-setting air box. The heat-setting air box contains a heat treatment channel for the continuous passage of long filaments. The heat-setting air box includes a box body, a filament-passing gantry, an upper air cushion stabilizing plate, a lower air cushion stabilizing plate, an upper air inlet diverting block, and a lower air inlet diverting block. The filament-passing gantry is vertically fixed to the bottom wall of the box body. The upper and lower air cushion stabilizing plates are parallel and symmetrically arranged inside the filament-passing gantry, and a flat filament passage is formed between the inner surfaces of the upper and lower air cushion stabilizing plates for the long filaments to pass through. The upper air inlet diverting block and... The lower air inlet diverter block is sealed and fastened to the outer side wall of the upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate respectively. The upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate are provided with static pressure flow stabilizing cavities. The internal cavities of the upper air inlet diverter block and the lower air inlet diverter block are respectively connected to the static pressure flow stabilizing cavities inside the upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate. The upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate are provided with slit-type jet nozzles near the filament inlet end, which are connected to the static pressure flow stabilizing cavities and extend obliquely toward the filament running direction. The outlet end of the slit-type jet nozzle is connected to an arc-shaped guide surface that gradually convexes toward the inside of the filament running channel.

[0007] By utilizing a gantry frame inside the housing to support upper and lower air cushion flow stabilizers, and by incorporating a static pressure flow stabilizing chamber and a slit-type jet nozzle extending obliquely towards the filament running direction within the flow stabilizers, high-pressure hot air enters the static pressure flow stabilizing chamber after being stabilized and diverted by the inlet air diverter block, and is ejected from the slit-type jet nozzle at a specific angle. This creates a Coanda effect by flowing along the curved guide surface, forming a uniform, stable, and highly rigid non-contact thermal air cushion support on both sides of the polymer filaments between the upper and lower air cushion flow stabilizers. This high-speed... The hot airflow provides forward aerodynamic traction and stable suspension for the high-speed filaments, thereby eliminating surface scratches, fuzzing, or adhesion defects caused by traditional mechanical contact support to filaments in a softened state at high temperatures. On the other hand, the airflow smoothly enters the flat filament running channel along the arc-shaped guide surface, reducing fluid resistance and local vortices, enhancing the convective heat transfer efficiency between the hot air and the filaments, ensuring uniform heating across the entire filament cross-section and consistent heat-setting crystallinity, thus improving the quality stability of spinning, drawing, and setting, and the operating efficiency of the production line.

[0008] Preferably, the upper air cushion flow stabilizer and the lower air cushion flow stabilizer are arranged at an inclined angle from the filament inlet end to the filament outlet end on the inner side of the filament running channel, forming a converging flow channel, which is wedge-shaped with a wide front end and a narrow rear end.

[0009] By designing the inner surfaces of the upper and lower air cushion flow stabilizers as wedge-shaped converging channels that slope towards the filament exit end, the cross-sectional area of ​​the channel decreases along the flow path as the filament moves towards the exit end. This causes the hot airflow within the channel to accelerate along the flow path, increasing the flow velocity and leading to an increase in the fluid dynamic pressure and a decrease in the static pressure. This results in a continuous and increasing forward aerodynamic traction force and fluid dynamic pressure levitation force on the filament surface. The wedge-shaped converging channel not only further enhances the axial orientation and straightness of the molecular chains in the filament during heat treatment but also strengthens the self-repairing torque of the levitation air cushion against the vertical drift of the filament, preventing high-frequency vibration or collision and adhesion to the cavity wall during high-speed drawing.

[0010] Preferably, in the middle section of the dynamic pressure convergence channel, the inner surfaces of the upper air cushion flow stabilizer and the lower air cushion flow stabilizer are provided with several pressure self-balancing compensation grooves that are transversely perpendicular to the filament running direction. The pressure self-balancing compensation grooves are provided with internal through holes, and the pressure self-balancing compensation grooves are connected to the corresponding static pressure flow stabilizer through the internal through holes.

[0011] By creating a pressure self-balancing compensation groove perpendicular to the filament running direction in the middle section of the dynamic pressure convergence channel, and connecting it to the static pressure stabilizing cavity through an internal through-hole, when the high-speed running filament yaws vertically due to local tension fluctuations or airflow disturbances, the gap in the filament running channel on the yaw side narrows, causing a transient increase in airflow pressure in that area. This excessive pressure can be quickly released into the static pressure stabilizing cavity or undergo fluid self-balancing through the pressure self-balancing compensation groove and the internal through-hole. Conversely, on the side where the gap widens, supplementary airflow is released in time through the internal through-hole. This forms a fluid dynamic negative feedback response and self-balancing adjustment for the filament suspension height, thereby eliminating the self-excited vibration and cross-groove jitter that easily occur in the middle section of the convergence channel, ensuring the stability of the spacing between multiple parallel running filaments, and preventing the filaments from crossing and tangling.

[0012] Preferably, the areas of the upper and lower air cushion flow stabilizers near the filament outlet gradually widen to form a turbulence elimination and diffusion section, and the inner surface of the turbulence elimination and diffusion section is densely distributed with an array of return air holes that are connected to the external return air duct.

[0013] By setting a gradually widening turbulence elimination and diffusion section at the filament outlet of the flow stabilizer plate and densely arranging an array of return air holes on the inner surface, the hot airflow ejected at high speed from the converging flow channel gradually decelerates and expands at the filament outlet. The return air is then distributed and orderly extracted through the return air micro-holes, effectively avoiding the generation of violent separation vortices and backflow turbulence at the abrupt change in the outlet cross section of the heat-setting air box due to high-speed airflow. This not only prevents the filament ends from swinging and uneven heating caused by turbulence at the outlet, but also achieves closed-loop efficient recycling of hot air, reduces system heat loss, and ensures that the filaments achieve stable cooling and uniform stress release before exiting the heat-setting air box.

[0014] Preferably, positioning guide holes are provided at the four corners of the upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate. A guide optical shaft is slidably connected in the positioning guide hole, and one end of the guide optical shaft is fixedly connected to the thread guide gantry. A bidirectional synchronous screw is rotatably installed on the thread guide gantry. The bidirectional synchronous screw has two threaded sections with opposite directions of rotation, which are threadedly engaged with the upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate respectively, so as to drive the upper air cushion flow stabilizer plate and the lower air cushion flow stabilizer plate to perform synchronous displacement in opposite directions.

[0015] By installing a bidirectional synchronous screw on the filament gantry and cooperating with guide shafts arranged at the four corners, when the bidirectional synchronous screw is rotated, the two threaded sections with opposite directions synchronously drive the upper and lower air cushion flow stabilizers to move symmetrically in opposite directions along the guide shafts, realizing stepless quantitative adjustment of the upper and lower gaps of the filament running channel. This allows the entire device to flexibly and accurately set the optimal running gap according to different fineness, different specifications of filament products, or different air cushion stiffness requirements, overcoming the limitations of traditional fixed bellows gaps that cannot adapt to the heat setting process requirements of various polymer filaments, thereby expanding the process applicability and adjustment convenience of the equipment.

[0016] Preferably, a reset damping spring is fitted around the outer periphery of the guide optical axis, and the reset damping spring is in a pre-compressed state abutting against the outer side of the upper air cushion flow stabilizer and the wire guide gantry.

[0017] By installing a pre-compressed reset damping spring on the outer periphery of the guide shaft, the reset damping spring continuously applies a stable axial preload to the upper air cushion flow stabilizer plate. On the one hand, this eliminates the transmission backlash and assembly clearance between the bidirectional synchronous screw and the mating threads of the upper and lower flow stabilizers, ensuring high repeatability positioning accuracy for gap fine-tuning. On the other hand, the pre-compressed spring constitutes an elastic vibration absorption system with damping characteristics, which can effectively absorb and attenuate high-frequency micro-vibrations caused by high-temperature and high-pressure airflow impact or mechanical transmission, preventing the flow stabilizer plate from resonating or loosening under dynamic conditions, and ensuring the long-term stability of the flow field channel geometry and the vibration resistance and durability of the mechanical structure.

[0018] Preferably, it also includes a wire guide frame; two wire guide frames are provided, and the two wire guide frames are respectively fixed to the wire inlet end and the wire outlet end on the outside of the box. Multiple wire guide grooves are formed in a horizontal linear array on the wire guide frame, which are used to perform initial horizontal laying and positioning of the filament before the filament enters the filament running channel to receive heat setting.

[0019] By fixing guide frames with transverse linear array filament guide grooves at the inlet and outlet ends on the outside of the box, the filament guide grooves pre-emptively lay out and position the multiple parallel array filaments in a transverse linear array before they enter the heat-setting air box. This avoids the filaments from overlapping, becoming disordered, or tangling due to vibrations in the previous process before entering the air cushion suspension zone, ensuring that the filaments pass smoothly through the filament running channel in a uniform single-layer flat shape. At the same time, placing the filament guide frame in the room temperature zone outside the box prevents the filaments from rubbing and tearing against the guide grooves when they are softened by heat. This achieves a functional division of labor between room temperature mechanical precise positioning of the filaments and high temperature non-contact air cushion heat setting.

[0020] Preferably, the upper air cushion flow stabilizer and the lower air cushion flow stabilizer are rigidly fixed to the lateral sides by fastening kits with side flow field sealing plates, which are used to close the airflow pressure relief ports on the lateral sides of the filament running channel that are connected to the external environment.

[0021] By rigidly fixing the side flow field sealing plates on both sides of the upper and lower air cushion flow stabilizing plates, the airflow pressure relief openings on both sides of the filament running channel are sealed, establishing a laterally closed airflow boundary condition. This effectively prevents the pressure collapse at the channel edge and the imbalance of the flow field gradient caused by the large-scale lateral pressure relief escape of high-temperature and high-pressure airflow from both sides. The side sealing plate structure ensures that the airflow can only flow orderly along the longitudinal channel of the filament running, maintaining the high uniformity of air cushion support stiffness and thermal field distribution throughout the entire width direction. This ensures that the filaments at the edge position and the filaments at the center position have completely consistent heat-setting physical properties, improving the overall quality consistency of the product.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses a non-contact hot air cushion support to replace the traditional mechanical limiting structure. This not only achieves stable constraint on the movement trajectory of the grass fibers, avoiding the problems of grass fiber surface fuzzing, scratching and fiber breakage caused by mechanical contact under high speed, but also eliminates the need to reduce the hot air circulation speed, ensuring heat setting efficiency and sufficient crystallization. At the same time, it eliminates the need to extend the axial length of the heat setting air box, reducing the equipment footprint and production energy consumption, and adapting to the needs of high-capacity continuous production.

[0023] 2. This invention achieves fluid self-regulation of the grass fiber suspension state through the acceleration effect along the flow path of the converging channel and the pressure self-balancing compensation structure, effectively suppressing the self-excited vibration and lateral shaking caused by high-speed airflow, avoiding entanglement and crossing between filaments, and ensuring the operational stability of multiple grass fibers.

[0024] 3. This invention can steplessly adjust the gap size of the filament running channel, which can adapt to the heat setting process requirements of grass fibers with different fineness and specifications. The equipment has a wide range of applications, is easy to adjust, and has a uniform and stable overall flow field. The grass fibers at different positions across the entire width have good heating consistency, and the finished product has high uniformity of physical and mechanical properties, which significantly improves the production quality of artificial turf grass fibers. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the artificial turf fiber drawing, stretching, and shaping device of the present invention; Figure 2 This is a schematic diagram of the artificial turf fiber drawing, stretching and shaping device of the present invention after the box body has been removed; Figure 3 for Figure 2 A magnified view of a section at point A in the middle; Figure 4 for Figure 2 A magnified view of a section at point B in the middle; Figure 5 This is a full sectional view of the artificial turf fiber drawing, stretching, and shaping device of the present invention; Figure 6 for Figure 5 A magnified view of a section at point C; Figure 7 This is a schematic diagram of the lower air cushion flow stabilizer plate in the artificial turf fiber drawing, stretching and shaping device of the present invention.

[0026] In the diagram: 1. Housing; 2. Wire guiding gantry; 3. Upper air cushion flow stabilizer; 4. Lower air cushion flow stabilizer; 5. Upper air inlet diverter block; 6. Lower air inlet diverter block; 7. Bidirectional synchronous screw; 8. Guide optical axis; 9. Reset damping spring; 10. Wire guide frame; 11. Side flow field sealing plate; 12. Wire running channel; 13. Static pressure flow stabilizing cavity; 14. Slit-type jet nozzle; 141. Arc-shaped flow guiding surface; 15. Converging channel; 16. Pressure self-balancing compensation groove; 161. Internal through hole; 17. Turbulence elimination and diffusion section; 171. Array-type return air hole; 18. Positioning guide hole; 19. Wire splitting guide groove. Detailed Implementation

[0027] Please see Figures 1 to 7 This invention provides a device for drawing, stretching, and shaping artificial turf fibers, the technical solution of which is as follows: An artificial turf filament drawing, stretching, and setting device includes a front-stage stretching roller assembly, a rear-stage tension guiding mechanism, and a heat-setting air box installed between the front-stage stretching roller assembly and the rear-stage tension guiding mechanism. The front-stage stretching roller assembly and the rear-stage tension guiding mechanism are configured at the front and rear ends of the heat-setting air box, as is common in existing technology. The front-stage stretching roller assembly includes a preheating roller, a main stretching roller, and a speed difference drive motor arranged sequentially. It applies a predetermined mechanical axial stretch to the unoriented polymer filaments using the linear velocity difference between the main stretching roller and the preceding extrusion equipment. The rear-stage tension guiding mechanism includes a tension-balancing floating roller, a filament guide roller assembly, and a constant-tension take-up shaft, used to maintain a set spinning tension after the filaments exit the heat-setting air box and to smoothly wind the set filaments. (See also...) Figures 1 to 7 A device for drawing, stretching, and shaping artificial turf filaments includes a housing 1, a filament-passing gantry 2, an upper air cushion flow stabilizer 3, a lower air cushion flow stabilizer 4, an upper air inlet diverter block 5, a lower air inlet diverter block 6, a bidirectional synchronous screw 7, a guide shaft 8, a reset damping spring 9, a filament guide frame 10, and a side flow field sealing plate 11. The housing 1 has a built-in heat treatment channel for continuous filament passage. The filament-passing gantry 2 is vertically fixed to the bottom wall of the housing 1. The upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4 are parallel and symmetrically arranged inside the filament-passing gantry 2. A flat filament running channel 12 for filaments to pass through is formed between the inner surfaces of the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4; the inner surfaces of the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4 facing the filament running channel 12 are arranged at an angle from the filament inlet end to the filament outlet end, forming a wedge-shaped dynamic pressure convergence channel 15 that is wide at the front end and narrow at the rear end; the upper air inlet diverter block 5 and the lower air inlet diverter block 6 are respectively sealed and fastened to the outer side walls of the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4, and a static pressure stabilizing cavity 13 is opened inside the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4. The internal cavities of the air inlet splitter block 5 and the lower air inlet splitter block 6 are respectively connected to the static pressure stabilizing cavities 13 inside the upper air cushion stabilizing plate 3 and the lower air cushion stabilizing plate 4; both the upper air cushion stabilizing plate 3 and the lower air cushion stabilizing plate 4 have slit-type jet nozzles 14 near the filament inlet end, which are connected to the static pressure stabilizing cavities 13 and extend obliquely towards the filament running direction. The outlet end of the slit-type jet nozzle 14 is connected to an arc-shaped guide surface 141 that gradually bulges into the inner side of the filament running channel 12 and has a smooth arc surface; in the middle section of the wedge-shaped dynamic pressure convergence channel 15, the upper air cushion stabilizing... Several pressure self-balancing compensation grooves 16 are opened on the inner surface of the plate 3 and the lower air cushion flow stabilizing plate 4, which are perpendicular to the filament running direction. Each pressure self-balancing compensation groove 16 has an internal through hole 161. The pressure self-balancing compensation groove 16 is connected to the corresponding static pressure flow stabilizing cavity 13 through the internal through hole 161. The area of ​​the upper air cushion flow stabilizing plate 3 and the lower air cushion flow stabilizing plate 4 near the filament exit end gradually widens to form a turbulence elimination and diffusion section 17. The inner surface of the turbulence elimination and diffusion section 17 is densely distributed with an array of return air holes 171 that are connected to the external return air duct.

[0028] Positioning guide holes 18 are provided at the four corners of the upper air cushion stabilizer plate 3 and the lower air cushion stabilizer plate 4. A guide shaft 8 slides through the positioning guide holes 18, and one end of the guide shaft 8 is fixedly connected to the thread guide gantry 2. A bidirectional synchronous screw 7 is rotatably mounted on the thread guide gantry 2. The bidirectional synchronous screw 7 has two threaded sections with opposite directions of rotation. The two threaded sections are respectively threaded with the upper air cushion stabilizer plate 3 and the lower air cushion stabilizer plate 4 to drive the upper air cushion stabilizer plate 3 and the lower air cushion stabilizer plate 4 to move synchronously in opposite directions. A reset damping spring 9 is fitted around the outer periphery of the guide shaft 8. The reset damping spring 9 is pre-compressed. The state is abutting between the outer side of the upper air cushion flow stabilizer plate 3 and the end limiting structure set on the filament gantry 2; the inlet and outlet ends of the box body 1 are respectively fixedly installed with filament guide frames 10, and multiple filament guide grooves 19 are opened in a horizontal linear array on the filament guide frame 10, which are used to perform initial horizontal flat positioning of the filament before the filament enters the filament running channel 12 to receive heat setting; the side flow field sealing plates 11 are rigidly fixed on the horizontal sides of the upper air cushion flow stabilizer plate 3 and the lower air cushion flow stabilizer plate 4 by fastening kits, and the side flow field sealing plates 11 are used to close the airflow pressure relief ports on the horizontal sides of the filament running channel 12 that are connected to the external environment.

[0029] Working principle: Please refer to Figures 1 to 7 During the drawing, stretching, and heat-setting process of the polymer filaments for artificial turf, multiple parallel array filaments first pass through the guide frame 10 located at the filament inlet end on the outside of the housing 1. The filaments are then positioned laterally at room temperature using a transversely linear array of filament guide grooves 19, ensuring that the filaments smoothly enter the filament running channel 12 enclosed by the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4 in a uniform, single-layer flat laying posture. Simultaneously, an external high-pressure hot air source introduces the heat medium through the upper air inlet diverter block 5 and the lower air inlet diverter block 6 into the static pressure stabilizing chamber 13 inside the upper air cushion flow stabilizer 3 and the lower air cushion flow stabilizer 4 for pressure stabilization and expansion, and then ejects it at high speed from the obliquely extending slit-type jet nozzle 14. When the high-speed hot airflow passes through the arc-shaped guide surface 141 at the outlet end, it undergoes a wall adhesion effect (Coanda effect), smoothly adheres to the smooth arc surface and turns to flow into the filament running channel 12. A high-rigidity and high-uniformity non-contact hot air cushion support is established between the upper air cushion stabilizing plate 3, the lower air cushion stabilizing plate 4 and the suspended filament, so that the polymer filament is completely suspended in the center of the channel in the state of softening due to heat, which completely avoids the defects of roughness, scratches or adhesion caused by mechanical hard contact friction.

[0030] As the filament moves along the filament running channel 12 toward the exit end, the hot airflow enters the wedge-shaped dynamic pressure convergence channel 15, which is formed by the upper air cushion flow stabilizer plate 3 and the lower air cushion flow stabilizer plate 4 arranged at an inclined approach. As the flow cross-sectional area decreases along the path, the hot airflow velocity increases and the static pressure decreases along the path, applying a continuous forward aerodynamic tensile force to the filament surface to maintain the molecular chain axial orientation of the filament during the crystallization and shaping process. When the filament yaws or vibrates in the middle section of the wedge-shaped dynamic pressure convergence channel 15 due to local tension fluctuations, the gap of the filament running channel 12 on the yaw side becomes transiently narrowed, causing a sudden increase in airflow pressure in that area. At this time, the excessive pressure is quickly released to the static pressure stabilization cavity 13 through the pressure self-balancing compensation groove 16 and the internal through hole 161, while the airflow is supplemented by the internal through hole 161 on the gap widening side, thereby forming a millisecond-level fluid adaptive negative feedback regulation, which self-corrects the suspension height of the filament and eliminates self-excited vibration under high wind speed. When the airflow passes through the turbulence elimination and diffusion section 17 at the filament exit end, the cross-section gradually widens, causing the flow velocity to decrease slowly. Most of the hot airflow is orderly drawn into the return air duct for recycling through the array of return air holes 171, eliminating the violent vortex and detachment backflow at the abrupt change in the cross-section of the wind box outlet, ensuring the stable release of filament stress at the filament exit end and the consistency of convective heat transfer quality.

[0031] When switching processes for polymer filaments with different fineness specifications or material properties, the operator rotates the bidirectional synchronous screw 7 mounted on the filament guide gantry 2. The screw's oppositely rotating threads drive the upper air cushion stabilizer plate 3 and the lower air cushion stabilizer plate 4 to perform high-precision symmetrical translation along the guide axis 8 within the positioning guide hole 18, thereby precisely fine-tuning the vertical clearance and air cushion thickness of the filament running channel 12. During this process, the pre-compressed reset damping spring 9, fitted around the guide axis 8, continuously presses against the upper air cushion stabilizer plate 3 and the filament guide gantry 2. This not only eliminates the circumferential backlash and assembly idle distance of the screw drive pair, greatly improving the repeatability of clearance adjustment, but also forms an elastic damping barrier, absorbing and attenuating the high-frequency micro-vibrations generated by the high-pressure hot air and mechanical operation. Meanwhile, the side flow field sealing plates 11, which are rigidly fixed to the upper air cushion flow stabilizer plate 3 and the lower air cushion flow stabilizer plate 4 on both sides of the lateral flow field, block the escape path of the lateral airflow pressure relief, ensuring that the flow field pressure and the height of the thermal field are the same in the full width direction. Finally, the filaments are guided out by the filament guide frame 10 at the filament outlet end, so as to achieve high-quality and high-efficiency filament drawing, stretching and shaping of artificial turf filaments.

[0032] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. A device for drawing, stretching, and shaping artificial turf fibers, comprising a heat-setting air box, wherein the heat-setting air box is provided with a heat treatment channel for continuous passage of long filaments, characterized in that... The heat-setting air box includes a box body (1), a thread-passing gantry (2), an upper air cushion flow stabilizer (3), a lower air cushion flow stabilizer (4), an upper air inlet diverter (5), and a lower air inlet diverter (6). The thread-passing gantry (2) is vertically fixedly installed on the bottom wall of the box body (1). The upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) are parallel and symmetrically arranged inside the thread-passing gantry (2). A flat filament running channel (12) for filaments to pass through is formed between the inner sides of the upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4). The upper air inlet diverter (5) and the lower air inlet diverter (6) are respectively fixedly installed on the upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4). The outer wall of the flow plate (4) is provided with a static pressure stabilizing cavity (13) inside the upper air cushion flow stabilizing plate (3) and the lower air cushion flow stabilizing plate (4). The internal cavities of the upper air inlet diverting block (5) and the lower air inlet diverting block (6) are respectively connected to the static pressure stabilizing cavity (13) inside the upper air cushion flow stabilizing plate (3) and the lower air cushion flow stabilizing plate (4). The upper air cushion flow stabilizing plate (3) and the lower air cushion flow stabilizing plate (4) are provided with a slit-type jet nozzle (14) that is connected to the static pressure stabilizing cavity (13) and extends obliquely toward the filament running direction. The outlet end of the slit-type jet nozzle (14) is connected to an arc-shaped guide surface (141) that gradually convexes toward the inside of the filament running channel (12).

2. The artificial turf fiber drawing, stretching, and shaping device according to claim 1, characterized in that, The upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) are arranged at an incline from the inlet end to the outlet end of the filament running channel (12) to form a converging flow channel (15), which is wedge-shaped with a wide front end and a narrow rear end.

3. The artificial turf fiber drawing, stretching, and shaping device according to claim 2, characterized in that, In the middle section of the convergent flow channel (15), the inner surfaces of the upper air cushion flow stabilizer plate (3) and the lower air cushion flow stabilizer plate (4) are provided with several pressure self-balancing compensation grooves (16) that are perpendicular to the filament running direction. The pressure self-balancing compensation grooves (16) are provided with internal through holes (161). The pressure self-balancing compensation grooves (16) are connected to the corresponding static pressure flow stabilizer cavity (13) through the internal through holes (161).

4. The artificial turf fiber drawing, stretching, and shaping device according to claim 3, characterized in that, The upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) gradually widen in the area near the filament outlet to form a turbulence elimination and diffusion section (17). The inner surface of the turbulence elimination and diffusion section (17) is densely distributed with an array of return air holes (171) that are connected to the external return air duct.

5. The artificial turf fiber drawing, stretching, and shaping device according to claim 1, characterized in that, The upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) are provided with positioning guide holes (18) at their four corners. A guide optical shaft (8) is slidably connected in the positioning guide hole (18). One end of the guide optical shaft (8) is fixedly connected to the thread gantry (2). A bidirectional synchronous screw (7) is rotatably installed on the thread gantry (2). The bidirectional synchronous screw (7) has two threaded sections with opposite directions of rotation, which are threadedly engaged with the upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) respectively, so as to drive the upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) to make synchronous displacements in opposite directions.

6. The artificial turf fiber drawing, stretching, and shaping device according to claim 5, characterized in that, The guide optical axis (8) is fitted with a reset damping spring (9) on its outer periphery. The reset damping spring (9) is in a pre-compressed state and abuts against the outer side of the upper air cushion flow plate (3) and the wire gantry (2).

7. The artificial turf fiber drawing, stretching, and shaping device according to claim 1, characterized in that, It also includes a wire guide frame (10); there are two wire guide frames (10), which are respectively fixed to the wire inlet end and the wire outlet end on the outside of the box (1). Multiple wire guide grooves (19) are opened on the wire guide frame (10) in a horizontal linear array to perform initial horizontal laying and positioning of the filament before it enters the filament running channel (12) to receive heat setting.

8. The artificial turf fiber drawing, stretching, and shaping device according to claim 1, characterized in that, The upper air cushion flow stabilizer (3) and the lower air cushion flow stabilizer (4) are rigidly fixed with side flow field sealing plates (11) on both sides by fastening kits. The side flow field sealing plates (11) are used to close the lateral sides of the filament running channel (12).

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