Continuous flat pressing type wood fiber and carbon fiber composite flame-retardant wall material preparation device

Abstract

The invention relates to the technical field of building composite material manufacturing, and discloses a continuous flat pressing type wood fiber and carbon fiber composite flame-retardant wall material preparation device which sequentially comprises, in the production process direction, a paving unit used for guiding carbon fibers and wood fibers in a layered mode and converging the carbon fibers and the wood fibers on a conveying device to form an initial blank of a sandwich structure; the fiber implanting and micro-channel constructing unit is arranged behind the paving unit and is used for implanting fibers on the surface layer of the initial blank into a core layer and constructing a micro-channel in the plate blank; the pre-pressing unit is arranged behind the fiber implantation and micro-channel construction unit and is used for carrying out wave deformation treatment on the plate blank and closing the micro-channel; and the continuous flat pressing machine is arranged behind the pre-pressing unit and is used for carrying out hot pressing forming and lateral restraining on the plate blank. The piezoelectric ceramic transducer is coupled to the back face of the convergence guide plate, the friction coefficient between fibers and the wall face is remarkably reduced through high-frequency micro-amplitude vibration, and the bridging effect caused by Van der Waals force between the fibers is effectively destroyed.

Description

Technical Field

[0001] This invention relates to the field of building composite material manufacturing technology, specifically to a continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device. Background Technology

[0002] In the preparation of existing flat-pressed wood fiber and carbon fiber composite fire-retardant wall materials, the traditional dry-process board manufacturing process in the fiber laying stage generally relies on airflow and gravity settling mechanisms. However, carbon fiber and wood fiber have significant differences in aerodynamic properties such as density, aspect ratio, and surface roughness. When these two materials are mixed in the same airflow field, mass separation is highly likely to occur, leading to uneven distribution of components within the board and the formation of local agglomerates or areas with low fiber content. Even with layered laying, the lack of mandatory flow guidance makes the fibers susceptible to environmental turbulence during settling, resulting in unclear interlayer interfaces and difficulty in constructing the intended gradient functional structure. This directly leads to large dispersion in the mechanical properties of the final product, failing to meet the standardized requirements of high-end building structures.

[0003] A more challenging issue is the interlaminar bonding and Z-axis reinforcement. Carbon fiber possesses high modulus and chemical inertness, while wood fiber is rich in hydroxyl groups on its surface, resulting in inherently poor interfacial compatibility. Existing planar hot-pressing processes struggle to achieve effective chemical bonding, making the sheets highly susceptible to interlaminar delamination during service due to stress release. While there are attempts in the industry to introduce Z-axis fibers using needle punching, the high-speed penetration of brittle carbon fibers often leads to shear fracture, disrupting the continuity of the reinforcement and creating stress concentration points within the sheet. In other words, achieving vertical implantation and mechanical anchoring of brittle fibers in a soft matrix without damaging them remains an unresolved technological paradox.

[0004] Furthermore, the deep impregnation and venting of thick-gauge fire-retardant boards present a difficult contradiction. To achieve high-level flame retardant standards, it is essential to ensure that the flame-retardant adhesive penetrates to the core layer of the board. However, the dense fiberboard blank naturally possesses a filtering effect, and conventional surface spraying or roller coating processes can only treat the surface layer, making it difficult to reach the core layer. While high-pressure impregnation solves the penetration problem, it often results in the inability to timely expel gases from within the blank. These residual high-pressure gases, upon thermal expansion during subsequent hot pressing, can easily cause the board to blister or delaminate, severely restricting production efficiency and yield. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a continuous flat-press wood fiber and carbon fiber composite flame-retardant wall material preparation device. It solves the core process problems in existing technologies, such as uneven component distribution and blurred interlayer interfaces caused by the difference in physical properties between carbon fiber and wood fiber in dry paving, easy fracture failure of brittle reinforcement due to traditional mechanical puncture, and difficulty in impregnating core layer flame retardant and venting internal air masses in continuous production of thick-gauge boards.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device, comprising, along the production process direction, the following components: The laying unit is used to guide carbon fiber and wood fiber in layers and converge them on a conveying device to form a sandwich structure preform. The fiber implantation and microchannel construction unit is located after the paving unit and is used to implant the fibers on the surface of the preform into the core layer and construct microchannels inside the preform. The pre-compression unit, located after the fiber implantation and microchannel construction unit, is used to perform wave deformation treatment on the slab and close the microchannels; A continuous flat press, located after the pre-pressing unit, is used for hot pressing and lateral restraint of slabs.

[0007] Preferably, the paving unit includes a precision partitioned metering chamber with physical partitions inside, dividing its internal storage space into a front chamber for storing bottom carbon fibers, a middle chamber for storing core wood fibers, and a rear chamber for storing surface carbon fibers. Each chamber is equipped with an independently driven synchronous metering roller at the bottom. An ultrasonic vibration guiding channel is provided below the synchronous metering roller. The ultrasonic vibration guiding channel is composed of a set of converging metal guide plates, which guide the materials discharged from the front, middle, and rear chambers to three independent laminar flow paths.

[0008] Preferably, a piezoelectric ceramic ultrasonic transducer is attached to the back of the metal guide plate to drive the metal guide plate to generate high-frequency micro-amplitude vibration, thereby reducing the coefficient of friction between the fiber and the wall of the metal guide plate.

[0009] Preferably, the fiber implantation and microchannel construction unit includes multiple cam disks sleeved and fixedly connected to the hollow main shaft. The multiple cam disks are evenly arranged to form a disk array spanning the width of the slab. The edges of the cam disks are machined with continuous blunt round cam lobes. The disk array is driven by an independent driving device to rotate at a linear speed greater than the slab's travel speed. The speed difference, in conjunction with the blunt round cam lobes, presses the surface carbon fiber to the core layer to form folded nodes.

[0010] Preferably, the hollow main shaft is connected to the output end of the pulse dispensing machine, and the side of the cam disc is provided with a dispensing channel that communicates with the inside of the hollow main shaft. Under the action of centrifugal force, the flame-retardant adhesive is pressed into the microchannel formed by the blank along the blunt round cam lobes.

[0011] Preferably, the pre-compression unit includes a vertically aligned upper wave roller and a lower wave roller, the circumferential contour of their radial cross sections being a continuous sinusoidal wave shape. The upper wave roller and the lower wave roller are synchronously driven by a rigid transmission mechanism, and there is a constant equidistant meshing gap between them, maintaining a constant phase difference so that the crest of the upper wave roller always corresponds to the trough of the lower wave roller.

[0012] Preferably, the continuous flat press includes independently driven upper and lower steel belts that operate at a set linear speed difference, thereby generating continuous surface shear stress in the slab thickness direction.

[0013] Preferably, both sides of the continuous flat press are provided with lateral high-frequency pulse mechanical constraint components. The lateral high-frequency pulse mechanical constraint components include rigid side baffles driven by an eccentric mechanism, which are used to apply high-frequency reciprocating pulse extrusion to the side of the slab to stimulate the thixotropy of the slab core layer and resist the Poisson expansion force when the slab is compressed.

[0014] Preferably, the opposing surfaces of the two rigid side baffles are processed with a forward barbed unidirectional texture, the direction of which is the same as the direction of the blank's travel, and is used to push the fibers overflowing from the edge of the blank back into the core layer during the pulse extrusion process.

[0015] This invention provides a continuous flat-press type apparatus for preparing fire-retardant wall materials made of wood fiber and carbon fiber composites. It has the following beneficial effects: 1. This invention significantly reduces the friction coefficient between fibers and the wall surface by coupling a piezoelectric ceramic transducer to the back of a convergent guide plate, effectively disrupting the "bridging" effect caused by van der Waals forces between fibers. This mechanical design forces loose heterogeneous fibers to settle in a laminar flow state, strictly following a pre-defined physical flow path. This constructs a "sandwich" gradient structure with a clear interface and precise component distribution without relying on uncontrollable airflow disturbances, providing a uniform material basis for subsequent Z-axis reinforcement. Simultaneously, through the "overspeed rolling" mechanism of the cam disk array, the tangential thrust generated by the linear velocity difference, combined with the pressing of blunt rounded lobes, gently pushes the surface rigid carbon fibers into the core layer in an "Ω"-shaped fold. This non-cutting physical implantation logic not only preserves the axial tensile strength of long carbon fibers but also achieves interlayer mechanical interlocking through in-situ constructed three-dimensional folding nodes, fundamentally solving the problem of weak bonding force of high-modulus reinforcement in a wood matrix. 2. This invention uses phase-meshing rollers to forcefully pre-press the slab into a wavy shape, inducing intense horizontal shear flow within the slab during the subsequent flattening process. This shear force, generated by geometric topological changes, can misalign, twist, and forcibly close the vertical microchannels left by the implantation operation in the previous steps. This process transforms what were originally "pinholes" of structural damage into "mechanical locks" that lock the internal flame-retardant adhesive and fix the fiber folding shape, achieving self-healing of the slab's microstructure. Simultaneously, the lateral high-frequency pulse constraint component uses mechanical vibration to excite the thixotropy of the core wood fiber-adhesive system, causing it to momentarily exhibit a fluid-like state. This liquefied matrix can rapidly fill and tightly encapsulate the carbon fiber folding structure with high elastic potential energy. Combined with the dynamic counteraction of lateral pulse pressure and Poisson's expansion force, the potential for interlayer delamination induced by internal stress is completely eliminated during the critical stage of slab forming and curing. Attached Figure Description

[0016] Figure 1 This is a perspective view of the present invention; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is a front view of the present invention; Figure 4 This is a schematic diagram of the internal structure of the precision partitioned metering chamber in this invention; Figure 5 This is a cross-sectional schematic diagram of the cam disk in this invention; Figure 6 This is a schematic diagram of the coupling between the upper and lower wave rollers in this invention; Figure 7 This is a side view of the continuous flat press in this invention.

[0017] Among them, 10 is the paving unit; 101 is the precision partition metering bin; 1011 is the front cavity; 1012 is the middle cavity; 1013 is the rear cavity; 102 is the physical partition; 103 is the synchronous metering feed roller; 104 is the metal guide plate; 20 is the conveying device; 30 is the fiber implantation and microchannel construction unit; 301 is the cam disc; 3011 is the glue injection channel; 302 is the hollow main shaft; 40 is the pre-compression unit; 401 is the upper corrugated roller; 402 is the lower corrugated roller; 50 is the continuous flat press; 501 is the upper steel belt; 502 is the lower steel belt; and 503 is the rigid side baffle. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see the appendix Figure 1 - Appendix Figure 7 This invention provides a continuous flat-press wood fiber and carbon fiber composite fire-retardant wall material preparation device. The device is designed as a highly integrated continuous automated production line, aiming to solve the process bottlenecks of weak interfacial bonding and difficult core impregnation in the heterogeneous fiber composite process through the physical coupling of pure mechanical structures.

[0020] The device, along the production process direction, includes, in sequence: The laying unit 10 is used to guide carbon fiber and wood fiber in layers and converge them on the conveying device 20 to form a sandwich structure preform. The fiber implantation and microchannel construction unit 30 is located after the laying unit 10 and is used to implant the fibers on the surface of the blank into the core layer and construct microchannels inside the blank. The pre-compression unit 40 is located after the fiber implantation and microchannel construction unit 30 and is used to perform wave deformation treatment on the slab and close the microchannels. The continuous flat press 50 is located after the pre-pressing unit 40 and is used to hot press the slab and provide lateral restraint.

[0021] These four units are physically connected by a mesh belt conveyor 20 or a transition roller table that runs through the entire line, forming a complete manufacturing closed loop from loose fiber raw materials to dense board products.

[0022] The connection relationships of each unit and the overall operating logic of the continuous flat-press wood fiber and carbon fiber composite fire-retardant wall material preparation device are as follows: The laying unit 10, as the starting point of the production line, is fixedly installed above the continuously operating forming mesh belt conveyor 20. This unit is configured to receive pre-prepared chopped carbon fiber filaments and glued wood fibers, and rely on an internal mechanical flow guiding structure to deposit the different components into the uniformly moving mesh belt below in a preset order. The function of this unit is to construct a sandwich structure preform with a clear interface of carbon fiber bottom layer, wood fiber core layer, and carbon fiber top layer, and to ensure the uniformity of the preform's mass distribution in the width direction, providing a material basis for subsequent processes.

[0023] The fiber implantation and microchannel construction unit 30 is positioned above the billet conveying path, between the outlet of the laying unit 10 and the inlet of the pre-compression unit 40. This unit uses a high-speed rotating mechanical actuator to physically contact the billet surface, utilizing the kinematic effect generated by the speed difference to vertically implant carbon fibers into the surface layer of the billet. Simultaneously, it intentionally creates open vertical channels, i.e., microchannels, along the billet thickness. This unit also integrates a fluid injection function, using the aforementioned microchannels to forcibly inject flame-retardant adhesive into the deep layers of the billet.

[0024] The pre-compression unit 40 is located downstream of the fiber implantation and microchannel construction unit 30 and consists of a pair of vertically aligned irregularly shaped rollers. After leaving the fiber implantation and microchannel construction unit 30, the slab directly enters the roller gap of the pre-compression unit 40. This unit uses forced geometric deformation to roll the originally flat slab with open microchannels into a wavy shape. During the process of the slab returning to flatness after leaving the unit, the shearing action generated by geometric recovery achieves the misalignment closure and self-sealing of the microchannels.

[0025] The continuous flat press 50 is located at the end of the production line and receives the pre-pressed slabs. The continuous flat press 50 typically includes a steel strip hot pressing system that circulates vertically and horizontally, as well as lateral restraint mechanisms on both sides. Under high temperature and high pressure, this unit performs final thickness shaping and resin curing on the slabs, while simultaneously eliminating residual stress within the slabs through active lateral mechanical restraint, ultimately outputting the finished sheet material.

[0026] The entire device is equipped with a central synchronous control system, which connects the servo drives of each unit via an industrial bus. The control system uses the conveyor belt speed of the conveyor 20 as a reference signal to adjust in real time the feeding speed of the laying unit 10, the rotational linear speed of the fiber implantation and microchannel construction unit 30, the roller speed of the pre-compression unit 40, and the steel belt running speed of the continuous flat press 50. This precise electrical synchronization ensures phase matching between the actions of each mechanical unit, enabling the fibers to precisely undergo a series of microstructural reorganization processes during continuous transport, including layering, folding implantation, shearing closure, and thixotropic locking.

[0027] The laying unit 10 includes a precision partitioned metering chamber 101, which has a physical partition 102 that divides its internal storage space into a front chamber 1011 for storing the bottom layer of carbon fibers, a middle chamber 1012 for storing the core layer of wood fibers, and a rear chamber 1013 for storing the surface layer of carbon fibers. Each chamber is equipped with an independently driven synchronous metering roller 103 at its bottom. Below the synchronous metering roller 103 is an ultrasonic excitation guide channel, which is composed of a set of converging metal guide plates 104. The metal guide plates 104 guide the materials discharged from the front chamber 1011, middle chamber 1012, and rear chamber 1013 to three independent laminar flow paths. A piezoelectric ceramic ultrasonic transducer is attached to the back of the metal guide plate 104 to drive the metal guide plate 104 to generate high-frequency micro-amplitude vibration, thereby reducing the coefficient of friction between the fibers and the wall of the metal guide plate 104.

[0028] In this embodiment, the laying unit 10 aims to solve the problems of randomness and uncontrollable stratification in the heterogeneous fiber airflow settling process by constructing a deterministic mechanical flow channel to achieve precise laminar flow distribution of components. The main body of the unit includes a precision partitioned metering chamber 101 and an ultrasonic excitation guide channel disposed below it.

[0029] The precision-divided metering chamber 101 is designed as an integral box structure. Its interior is strictly divided into three independent volume chambers by two vertically arranged physical partitions 102 (baffles): a front chamber 1011, a middle chamber 1012, and a rear chamber 1013, arranged sequentially along the slab's travel direction. The front chamber 1011 is specifically used to store the short-cut carbon fibers that make up the bottom layer of the slab; the middle chamber 1012 is used to store the sizing wood fibers that make up the core layer of the slab; and the rear chamber 1013 is used to store the short-cut carbon fibers that make up the surface layer of the slab. This physical separation design eliminates the disorderly mixing of different fibers before metering.

[0030] The bottoms of the three volumetric chambers are all open, and each is equipped with an independently driven synchronous metering roller 103. Each synchronous metering roller 103 is driven by its own servo motor via a reducer, and can independently adjust its speed according to the instructions of the central control system. By precisely controlling the speed ratio of the rollers in the front chamber 1011, the middle chamber 1012, and the rear chamber 1013, the system can adjust the volumetric flow rate ratio of carbon fiber and wood fiber in real time, thereby achieving closed-loop control of the interlayer density gradient and the thickness ratio of each layer in the final product.

[0031] Directly below the synchronous metering feed roller 103, a core ultrasonic vibration guiding channel is provided. This channel consists of a set of rigid metal guide plates 104 arranged in an inverted trapezoidal convergent shape. The metal guide plates 104 are finely machined into streamlined curved surfaces, and their surfaces are polished to reduce roughness. These guide plates spatially and strictly separate the material flow falling from 1011, the middle cavity 1012, and the rear cavity 1013 into three independent settling paths until they reach the confluence point at a preset height (e.g., 20-50 mm) above the surface of the conveyor belt below.

[0032] Several sets of piezoelectric ceramic ultrasonic transducers are tightly attached to the back of the metal guide plate 104. These transducers are connected to an external ultrasonic generator via high-frequency cables. During operation, the transducers drive the metal guide plate to generate high-frequency micro-amplitude mechanical vibrations at frequencies ranging from 20kHz to 40kHz. This continuous high-frequency vibration forms a microscopic air film on the working surface of the guide plate, greatly reducing the dynamic friction coefficient between the fiber material and the metal wall, allowing fibers that are originally viscous or easily entangled to slide smoothly like a fluid.

[0033] Furthermore, the ultrasonic vibration effectively breaks down agglomerates formed between microfibers due to van der Waals forces or electrostatic adsorption, preventing bridging or blockage at the constriction point of the guide plate. Thanks to this friction-reducing and deagglomeration mechanism, the three material streams can maintain a stable laminar flow and settle vertically in an environment free from external airflow interference.

[0034] Specifically, due to the spatial difference in the front and rear positions of the outlet of the metal guide plate 104, the carbon fiber flow discharged from the front cavity 1011 first contacts the running conveyor belt and lays up to form the bottom layer; then, the wood fiber flow discharged from the middle cavity 1012 smoothly covers the bottom layer to form the core layer; finally, the carbon fiber flow discharged from the rear cavity 1013 falls on the top surface of the core layer to form the surface layer. This mechanically determined laminar flow convergence process constructs a "carbon fiber-wood fiber-carbon fiber" sandwich preform with clear interfaces and no mixing of components, providing an ideal structural basis for the physical implantation operation in subsequent processes.

[0035] The fiber implantation and microchannel construction unit includes more than 30 cam disks 301 sleeved and fixedly connected to the hollow main shaft 302. These cam disks 301 are evenly arranged to form a disk array spanning the width of the slab. The edges of the cam disks 301 are machined with continuous blunt rounded cam lobes. An independent drive device drives the disk array to rotate at a linear velocity greater than the slab's travel speed. The velocity difference, combined with the blunt rounded cam lobes, presses the surface carbon fibers to the core layer, forming folded nodes. The hollow main shaft 302 is internally connected to the output end of a pulse injection machine. The cam disks 301 have injection channels 3011 on their sides that communicate with the interior of the hollow main shaft 302. Under centrifugal force, the flame-retardant adhesive is pressed into the microchannels formed on the slab along the blunt rounded cam lobes.

[0036] In this embodiment, the fiber implantation and microchannel construction unit 30 mainly performs two functions: first, to physically implant the surface carbon fiber into the core layer to enhance the interlayer bonding force; and second, to construct microchannels inside the slab for glue injection and venting. This unit is installed across the slab conveying path, and its main structure includes a set of parallel cam disc arrays, a hollow main shaft 302, and an integrated pulse glue injection system.

[0037] In this embodiment, the cam disk array consists of several metal cam disks 301 fixed at equal intervals (e.g., 10mm-30mm) on a horizontal hollow main shaft 302. The edges of each cam disk 301 are precision-machined to form a continuous blunt-rounded cam lobe structure. It is particularly noteworthy that the tooth tips of this lobe employ a large-radius arc transition design, completely eliminating the sharp edges of traditional needle-punching or cutting tools. This blunt-rounded profile is a key geometric feature for achieving flexible pressing rather than shearing damage, ensuring that the brittle carbon fiber filaments are not cut upon contact with the slab.

[0038] The power system of this unit is configured to drive the cam disk array to operate at a specific overspeed. Specifically, the linear velocity of the edge of the cam disk 301 is set to be constantly greater than the slab's travel speed on the conveyor belt, typically with the linear velocity ratio controlled between 1.05 and 1.20. When the high-speed rotating blunt rounded lobes cut into the slab surface, this velocity difference generates a horizontal tangential force pointing in the direction of slab travel at the point of contact.

[0039] Under the combined action of vertical pressure and horizontal tangential force, the rigid carbon fiber bundles, originally planar in shape, are gently captured by the lobes and forced into bending deformation. They are then pressed and pushed deep into the soft wood fiber core layer. Since no shear fracture occurs, the implanted carbon fibers form continuous Ω-shaped or U-shaped three-dimensional folded nodes within the core layer. These folded nodes will act like anchors in subsequent processes, significantly improving the Z-axis peel strength of the composite material.

[0040] The hollow spindle 302 is designed as a hollow tubular structure, with one end connected to an external pulse dispensing machine via a rotary joint. Radial liquid outlet holes are formed on the tube wall of the hollow spindle 302, corresponding to the position of each cam disc 301. Several micro-channels radiating from the axis to the root of the edge lobes are machined inside the disc body of each cam disc 301.

[0041] When the cam disk 301 rotates at high speed, the flame-retardant adhesive injected into the hollow main shaft 302 is thrown into the microchannels inside the cam disk 301 under the action of centrifugal force, and finally sprayed out at high speed from the injection port at the root of the cam lobe. At this time, since the cam lobe has just been pressed into the blank and is withdrawing, it leaves a vertical, temporarily open groove inside the blank, i.e., a microchannel. The centrifugally sprayed adhesive can accurately penetrate directly into the core area of ​​the blank along the wall of this microchannel, achieving saturated impregnation of the core layer of thick-gauge plates, and completely solving the problem that traditional surface spraying processes cannot penetrate the core layer. At the same time, these microchannels also provide a low-resistance channel for the exhaust of air from the core layer.

[0042] The pre-compression unit 40 includes an upper wave roller 401 and a lower wave roller 402 that are vertically aligned. The circumferential contour of the radial cross section of both rollers is a continuous sinusoidal wave. The upper wave roller 401 and the lower wave roller 402 are driven synchronously through a rigid transmission mechanism. A constant equidistant meshing gap is provided between them, and a constant phase difference is maintained so that the crest of the upper wave roller 401 always corresponds to the trough of the lower wave roller 402.

[0043] In this embodiment, the pre-compression unit 40 receives the slab after the implantation operation. Its core function is to induce internal shear flow through specific geometric deformation, thereby repairing microchannel damage and locking the internal structure. This unit mainly consists of an upper corrugated roller 401 and a lower corrugated roller 402 installed vertically aligned, and a rigid precision synchronous transmission mechanism connecting the two.

[0044] The upper corrugated roller 401 and the lower corrugated roller 402 are large-diameter metal rollers, and the circumferential contour of their radial cross sections is a continuous sinusoidal wave. The wavelength and wave height are set according to the bulk of the slab and the allowable bending radius of the fiber. The wave height is usually designed to be 30% to 40% of the original thickness of the slab to ensure that sufficient deformation can be generated without damaging the fiber skeleton.

[0045] To achieve effective forming of the slab, a strict phase meshing relationship must be maintained between the upper wavy roller 401 and the lower wavy roller 402. By employing zero-backlash precision gearbox or electronic shaft synchronization control technology, the two rollers rotate in opposite directions at perfectly synchronized linear velocities, maintaining a constant π-phase difference. This means that on the meshing line at the center of the two rollers, each crest of the upper wavy roller 401 precisely corresponds to each trough of the lower wavy roller 402. This meshing state creates a wavy, equidistant gap channel between the two rollers, ensuring that the slab is subjected to uniform normal compressive force as it passes through, forcibly rolling it into a continuous transverse wavy shape.

[0046] When the slab with vertical microchannels enters the pre-compression unit 40, it is first forced to bend into a wavy shape. At this time, the microchannels, which were originally perpendicular to the slab surface, open in a fan shape or are squeezed and deformed as the curvature of the slab changes, and a certain tilt angle is generated relative to the horizontal reference plane.

[0047] Subsequently, as the wavy slab leaves the rollers and enters the subsequent planar transition zone (e.g., the guide plate before entering the flat press), the slab is forced to undergo a geometric flattening process, returning from a "wavy" state to a "flat" state. During this process, the surface path length of the slab is forcibly shortened, and excess volume must be transferred inwards. This dramatic geometric recovery motion induces complex horizontal shear flows within the slab.

[0048] This shear flow primarily acts along the length of the slab, displacing and shifting the internal material like kneading dough. The direct result is that the vertical microchannels formed in the preceding steps are forcibly twisted, displaced, and eventually closed. This closure not only physically seals the deeply injected flame-retardant adhesive within the gaps between the core fibers, forcing it to permeate outwards rather than leak, but also locks the Ω-shaped folded nodes of the carbon fibers through mechanical interlocking, forming an interlocking structure similar to rivets. This achieves self-healing and initial reinforcement of the slab's microstructure.

[0049] The continuous flat press 50 includes independently driven upper steel belt 501 and lower steel belt 502, which operate at a set linear speed difference, thereby generating continuous surface shear stress in the thickness direction of the slab. Lateral high-frequency pulse mechanical constraint assemblies are provided on both sides of the continuous flat press 50. These lateral high-frequency pulse mechanical constraint assemblies include rigid side baffles 503 driven by an eccentric mechanism, used to apply high-frequency reciprocating pulse extrusion to the sides of the slab to stimulate the thixotropy of the slab core layer and resist Poisson's expansion force when the slab is compressed. The opposing surfaces of the two rigid side baffles 503 are machined with a unidirectional barbed texture, the direction of which is the same as the slab's travel direction, used to push fibers overflowing from the slab edge back into the core layer during pulse extrusion.

[0050] In this embodiment, the continuous flat press 50 serves as the final forming stage of the entire production line, responsible for densifying the slab, curing the adhesive, and eliminating internal stress under high temperature and high pressure conditions. It includes a micro-misaligned double steel belt hot pressing system and lateral high-frequency pulse mechanical constraint components integrated on both sides of the press.

[0051] The dual-strip hot pressing system consists of an upper strip 501 and a lower strip 502, each with its own independent drive roller assembly. Unlike conventional synchronous presses, the control system of this device is configured to drive the upper strip 501 and lower strip 502 with an extremely small difference in linear velocity (e.g., 0.05%-0.1%). This minute velocity mismatch introduces a continuous surface shear stress field in the thickness direction of the slab. This shear stress causes microscopic collapse of the fibers on the contact strip surface, eliminating vertically protruding burrs on the surface, while simultaneously promoting a slight rearrangement of fibers within the slab during the thermoplastic stage, further engaging the folded nodes formed in the previous process.

[0052] Lateral high-frequency pulse mechanical restraint components are installed on both sides of the hot-pressing section, close to the sides of the steel strip. The core component of this component is a pair of long, rigid side baffles 503 extending along the direction of plate movement. The inner surface of the rigid side baffles 503 (i.e., the surface in contact with the side of the slab) is coated with a Teflon low-friction coating and processed with a unidirectional barbed micro-texture in the same direction as the plate movement. This specific unidirectional texture design gives the sidewall anisotropic frictional characteristics: when the slab moves at high speed longitudinally, the edge fibers slide along the slope of the texture, resulting in extremely low frictional resistance, thereby preventing the fibers from being mechanically hooked or pulled out; while when the rigid side baffles 503 perform an inward pressing action, the wedge-shaped structure of the barbs can effectively embed into the loose edge layer, increasing the transmission efficiency of lateral thrust.

[0053] The rigid side baffle 503 is not statically fixed, but is connected to a high-frequency motor via an eccentric wheel linkage mechanism at its back. During press operation, the drive mechanism forces the rigid side baffle 503 to apply transverse reciprocating pulse compression with a frequency of 20Hz to 50Hz and an amplitude of 0.5mm to 2mm to the side of the slab being pressed. This high-frequency mechanical pulse induces a thixotropic rheological effect in the core layer of the slab.

[0054] Specifically, high-frequency vibration energy is transferred to the core layer, which is rich in adhesive and wood fiber, causing the apparent viscosity of the mixed matrix to drop sharply, exhibiting a liquid-like flow state. The liquefied matrix can quickly fill the tiny gaps around the carbon fiber "Ω" folded structure, achieving thorough wetting and encapsulation.

[0055] More importantly, the active inward pulse pressure applied by the rigid side baffle 503 forms a dynamic counterbalancing force with the lateral expansion force generated by the Poisson effect during the vertical compression of the slab. This active lateral constraint force constructs a uniform high-pressure turbulent field inside the slab, forcibly locking the three-dimensional orientation of the fibers and effectively counteracting the interlaminar separation tendency of high-modulus carbon fibers due to elastic recovery. As the slab moves forward with the steel strip and gradually cools, the matrix rapidly solidifies in a dense state, ultimately producing a composite fire-retardant wall panel with extremely high interlaminar bonding strength and dense edges.

[0056] Based on the aforementioned continuous flat-press wood fiber and carbon fiber composite fire-retardant wall material preparation device, this invention further provides a process method for preparing composite fire-retardant wall materials using this device. In this embodiment, the method achieves deterministic composite and structural reinforcement of heterogeneous fibers through a series of continuous and tightly coupled mechanical and physical actions.

[0057] First, the laying unit 10 is activated, and pre-measured chopped carbon fibers and bonded wood fibers are loaded into the front cavity 1011, rear cavity 1013, and middle cavity 1012 of the precision metering chamber 101, respectively. The ultrasonic generator is turned on, driving the lower metal guide plate 104 to generate high-frequency micro-amplitude vibrations. Under the dual drive of gravity and ultrasonic friction reduction, each component fiber steadily settles onto the conveyor belt along its own independent laminar flow path. The bottom layer of carbon fibers is laid first, followed by the core layer of wood fibers, and the surface layer of carbon fibers is stacked last, thus constructing a preliminary "carbon fiber-wood fiber-carbon fiber" sandwich structure with clear interfaces and no component doping on the conveyor belt.

[0058] Subsequently, the conveying device 20 carrying the blank delivers the material into the fiber implantation and microchannel construction unit 30. The rotational speed of the cam disk array is adjusted so that its linear velocity is constantly greater than the traveling speed of the blank (e.g., setting the overspeed ratio to 1.15). When the high-speed rotating blunt round cam lobes contact the surface of the blank, tangential thrust is used to gently fold and press the rigid carbon fiber bundles on the surface into the core layer, forming continuous "Ω"-shaped three-dimensional physical nodes. At the same time, as the cam lobes are pressed in and out, vertically open microchannels are left inside the blank. The pulse glue injection system is simultaneously activated, using centrifugal force to spray flame-retardant glue at high speed into the microchannels through the glue injection channel 3011, completing the deep impregnation of the core layer wood fibers.

[0059] Next, the slab, after implantation and adhesive injection, immediately enters the pre-compression unit 40. Under the precise meshing of the upper corrugated roller 401 and the lower corrugated roller 402, the slab is forced to roll into a transverse corrugated shape. During this process, the fibers inside the slab undergo initial densification. When the slab leaves the corrugated rollers and enters the subsequent planar transition area, it is forced to flatten from the corrugated shape back to a flat shape. This geometric deformation process induces intense horizontal shear flow inside the slab, which misaligns, twists, and forcibly closes the vertical microchannels formed in the previous step, thereby physically sealing the adhesive injected into the core layer and further interlocking and locking the folded structure of the carbon fibers.

[0060] Finally, the slab enters a continuous flat press 50 for final forming. Under high temperature (e.g., 180°C-220°C) and high pressure (e.g., 3MPa-5MPa), the upper steel strip 501 and lower steel strip 502 are set to run with a small speed difference of 0.1%, generating surface shear force to flatten the slab surface. Simultaneously, the lateral high-frequency pulse mechanical constraint assembly is activated, and the rigid side baffle 503 applies reciprocating pulse extrusion at a frequency of 30Hz to the side of the slab. This pulse action excites the thixotropic liquefaction of the core matrix, causing it to rapidly encapsulate the carbon fiber nodes and effectively counteract the lateral Poisson expansion of the slab under pressure. As the resin crosslinks and cures, the three-dimensional orientation of the fibers and the interlayer interlocking structure are permanently locked. After cooling and cutting, a composite wall material with high bonding strength and excellent flame-retardant properties is obtained.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device, characterized in that, Along the production process direction, it includes, in sequence: The laying unit (10) is used to guide carbon fiber and wood fiber in layers and converge them on the conveying device (20) to form a sandwich structure preform; The fiber implantation and microchannel construction unit (30) is located after the laying unit (10) and is used to implant the fibers of the initial blank surface into the core layer and construct microchannels inside the blank; The pre-compression unit (40) is located after the fiber implantation and microchannel construction unit (30) and is used to perform wave deformation treatment on the slab and close the microchannel; A continuous flat press (50) is installed after the pre-pressing unit (40) and is used to hot press and laterally constrain the slab.

2. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 1, characterized in that, The paving unit (10) includes a precision partition metering chamber (101), which is provided with a physical partition (102) to divide its internal storage space into a front chamber (1011) for storing bottom carbon fiber, a middle chamber (1012) for storing core wood fiber, and a rear chamber (1013) for storing surface carbon fiber. Each chamber is equipped with an independently driven synchronous metering roller (103) at the bottom. An ultrasonic excitation guide channel is provided below the synchronous metering roller (103). The ultrasonic excitation guide channel is composed of a set of converging metal guide plates (104). The metal guide plates (104) guide the material discharged from the front chamber (1011), middle chamber (1012) and rear chamber (1013) to three independent laminar flow paths.

3. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 2, characterized in that, A piezoelectric ceramic ultrasonic transducer is attached to the back of the metal guide plate (104) to drive the metal guide plate (104) to generate high-frequency micro-amplitude vibration, so as to reduce the friction coefficient between the fiber and the wall of the metal guide plate (104).

4. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 1, characterized in that, The fiber implantation and microchannel construction unit includes (30) multiple cam disks (301) sleeved and fixedly connected to the hollow main shaft (302) shaft. The multiple cam disks (301) are evenly arranged to form a disk array spanning the width of the slab. The edges of the cam disks (301) are processed with continuous blunt round cam lobes. The disk array is driven by an independent driving device to rotate at a linear speed greater than the slab's travel speed. The speed difference is used in conjunction with the blunt round cam lobes to press the surface carbon fiber to the core layer to form folded nodes.

5. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 4, characterized in that, The hollow spindle (302) is connected to the output end of the pulse dispensing machine. The side of the cam disc (301) is provided with a dispensing channel (3011) that communicates with the inside of the hollow spindle (302). Under the action of centrifugal force, the flame retardant adhesive is pressed into the microchannel formed by the blank along the blunt round cam lobes.

6. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 1, characterized in that, The pre-compression unit (40) includes an upper wave roller (401) and a lower wave roller (402) that are vertically aligned. The circumferential contour of the radial cross section of the two rollers is a continuous sinusoidal wave. The upper wave roller (401) and the lower wave roller (402) are driven synchronously by a rigid transmission mechanism. A constant equidistant meshing gap is provided between the two rollers, and a constant phase difference is maintained so that the peak of the upper wave roller (401) always corresponds to the trough of the lower wave roller (402).

7. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 1, characterized in that, The continuous flat press (50) includes an independently driven upper steel belt (501) and a lower steel belt (502), which operate at a set linear speed difference, thereby generating continuous surface shear stress in the slab thickness direction.

8. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 7, characterized in that, Both sides of the continuous flat press (50) are provided with lateral high-frequency pulse mechanical constraint components. The lateral high-frequency pulse mechanical constraint components include rigid side baffles (503) driven by an eccentric mechanism, which are used to apply high-frequency reciprocating pulse extrusion to the side of the slab to stimulate the thixotropy of the slab core layer and resist the Poisson expansion force when the slab is compressed.

9. The continuous flat-press type wood fiber and carbon fiber composite fire-retardant wall material preparation device according to claim 8, characterized in that, Both rigid side baffles (503) have unidirectional barbed textures on their opposite surfaces. The direction of the unidirectional barbed textures is the same as the direction of the slab's travel, and is used to push the fibers overflowing from the edge of the slab back into the core layer during pulse extrusion.

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