Deformation control devices, production lines, and applications for non-PVC wood-plastic composite panels.

Abstract

The present invention relates to the technology of flooring material manufacturing, and more particularly to a deformation control device, production line, and application for non-polyvinyl chloride wood-plastic composite board material. The deformation control device comprises a die fixedly connected to an extruder for outputting a semi-finished board material, and a take-roll unit composed of a combination of multiple take-rolls for taking and shaping the semi-finished board material. The die includes an output port for outputting the semi-finished board material, and a narrow angle exists between the output port and the horizontal plane, such that the direction in which the semi-finished board material is taken along the output port by the take-roll unit does not overlap with the direction of gravity acting on the semi-finished board material itself, and the narrow angle between the two is less than 90 degrees. The deformation control device in this application effectively overcomes the problems of shrinkage and warping during the extrusion process, which were not seen in conventional polyvinyl chloride board material, by changing the angular relationship between the output port of the die and the horizontal plane.

Description

[Technical Field]

[0001] The present invention relates to the technical field of flooring manufacturing, and in particular to a deformation control device for non-vinyl chloride wood-plastic panels, a production line and applications thereof. [Background Art]

[0002] In the field of panel manufacturing, flooring with three-dimensional solid wood grain has become a common option. By using advanced technology and materials, these flooring products can be produced to approximate natural wood in both visual and tactile aspects. These three-dimensional solid wood grain floorings have better performance and durability, and can meet consumers' demand for high-quality, low-maintenance and low-cost products. In addition, the manufacturing process of these products can reduce dependence on natural resources, thereby protecting the environment and promoting sustainable development.

[0003] Currently, three-dimensional solid wood grain flooring usually uses a panel containing polyvinyl chloride (PVC) as a base material, and forms the three-dimensional solid wood grain on the base material by printing or lamination. Polyvinyl chloride artificial panels have properties such as wear resistance, water resistance and corrosion resistance, so they have certain advantages in the production of flooring with three-dimensional solid wood grain.

[0004] For example, the patent with the grant publication number CN112095967B discloses a multi-layer synchronous forming round-edge PVC panel, which comprises a panel body, wherein the panel body sequentially comprises, from top to bottom, a UV paint layer, a PVC wear-resistant layer, a PVC pattern film layer, a PVC base plate and a PVC underlayer, the surface of the panel is provided with a synchronous simulated solid texture, arc edges and a locking structure are provided on four sides of the panel body, and panels can be locked and connected to each other through the locking structure.

[0005] The patent with publication number CN114953665A discloses a manufacturing process for PVC flooring and the resulting product. The specific manufacturing process includes steps to obtain a finished PVC flooring by sequentially laminating a PVC substrate layer, a PVC printed layer, and a PVC pre-coat film, and then performing a batch bonding process.

[0006] However, the use of polyvinyl chloride (PVC) artificial flooring materials has several insurmountable drawbacks in terms of recycling and environmental protection. Firstly, due to the structural properties of PVC, its recycling and reuse are relatively difficult, leading to resource waste. Secondly, PVC releases harmful substances during production, use, and processing, posing a potential risk to the environment and human health. Therefore, from an environmental protection standpoint, certain restrictions must be placed on the application of PVC in the flooring industry.

[0007] To address the shortcomings of polyvinyl chloride (PVC) artificial boards, researchers are beginning to explore alternative materials. Among these, polyolefin materials are considered one of the potential alternatives. A typical example of a polyolefin material is polypropylene, a non-PVC material with good physical properties and chemical stability. It can be used in the manufacture of artificial boards and can simulate a texture and feel similar to natural wood. Furthermore, polypropylene materials are recyclable and reusable, contributing to the reduction of resource waste and environmental pollution.

[0008] For example, the patent with publication number CN108659333A provides a non-polyvinyl chloride surface coating comprising a base layer, an intermediate layer located on the base layer and including a core layer, and a transparent abrasion-resistant layer located on the intermediate layer and containing 40-94.95% by weight of polyolefin, 5-50% by weight of polyolefin elastomer or polyolefin plastomer, and 0.05-10% by weight of a processing aid.

[0009] Furthermore, for example, the patent with publication number CN111267448A discloses a 3D printed flooring material made of non-PVC substrates, which includes a non-PVC substrate layer, on which a balance layer and a solid wood layer are sequentially provided, on which a UV primer layer is provided on the surface of the solid wood layer, on which a white UV paint layer is provided, on which a print pattern layer is provided on the surface of the white UV paint layer, and on which an unevenness effect layer is provided on the surface of the print pattern layer.

[0010] However, polyolefin materials (e.g., polypropylene) have high thermal shrinkage properties, meaning that polypropylene shrinks when the temperature changes during the manufacturing process. Such thermal shrinkage can cause uneven shrinkage of the board material during the cooling process, resulting in warping and ultimately leading to unevenness and instability of the flooring. Furthermore, the abrasion resistance of polyolefin materials differs to that of polyvinyl chloride. Therefore, to overcome these problems, it is necessary to improve the manufacturing methods and production equipment for board materials made from polyolefin materials, thereby contributing to improved quality, stability, and environmental compatibility of three-dimensional wood-grain flooring. [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] The objective of the present invention is to overcome the shortcomings of conventional non-polyvinyl chloride wood-plastic composite boards, which exhibit high warping during the molding process and result in uneven and unstable defects in the final flooring material, by providing a deformation control device, production line, and applications for non-polyvinyl chloride wood-plastic composite boards that solve the aforementioned problems. [Means for solving the problem]

[0012] To achieve the above objectives, the present invention is realized by the following technical means.

[0013] As a first aspect, the present invention first provides a deformation control device for non-polyvinyl chloride wood-plastic composite boards.

[0014] The apparatus is fixedly connected to an extruder and comprises a die for outputting semi-finished sheet material, and a take-roll unit consisting of a combination of multiple take-rolls for taking shape of the semi-finished sheet material. The die includes an output port for outputting the semi-finished sheet material, and there is a narrow angle between the output port and the horizontal plane. The direction in which the semi-finished sheet material is taken along the output port by the take-roll unit and the direction of gravity acting on the semi-finished sheet material itself do not coincide, and the narrow angle between the two is less than 90 degrees.

[0015] In conventional technology, sheet material substrates made from polyvinyl chloride (e.g., SPC substrates, LVT substrates) are typically manufactured using polyvinyl chloride as a polymer substrate, with stone powder added to it, and finally obtaining the required sheet material through extrusion molding. Because polyvinyl chloride is an amorphous polymer, the volume shrinkage rate before and after extrusion is low, and conventional polyvinyl chloride substrates did not require excessive consideration of warping caused by volume shrinkage during the manufacturing process. At the same time, polyvinyl chloride is highly polar, the viscosity of the molten material obtained by mixing and melting it with stone powder is high, and the hardness of the semi-finished sheet material obtained by letting the molten material flow out of the mold and cooling is high. Therefore, even when external forces are applied, the shape retention ability remains strong, and thus warping deformation is less likely to occur under the action of external forces and internal stresses.

[0016] In light of the reasons stated above, the current extrusion process for sheet material substrates made from polyvinyl chloride typically involves the raw material entering an extruder, being melted and plasticized, then being extruded from a horizontally installed mold to form a semi-finished sheet material. The semi-finished sheet material is then pulled horizontally into a cooling mechanism for cooling and final shaping. However, with the ever-increasing demand for environmental protection, upgrading and replacing polyvinyl chloride materials has become an urgent necessity. However, in the process of extruding new polyolefin-based sheet materials using conventional extrusion equipment, the applicant discovered previously unforeseen technical challenges. Specifically, polyolefin semi-finished sheet materials produced using conventional extrusion equipment exhibit high volume shrinkage and severe warping deformation, making them unsuitable for use in the manufacture of non-polyvinyl chloride wood-plastic composite sheets and non-polyvinyl chloride wood-plastic composite flooring.

[0017] In response, the applicant conducted in-depth research on the above phenomenon. The research revealed that the causes of severe warping deformation in non-PVC wood-plastic composite panels include at least the following: (1) Polyolefin materials have a more regular molecular chain, resulting in significantly higher crystalline properties than conventional polyvinyl chloride, which leads to volume shrinkage during the crystallization process. (2) At the same time, the viscosity of the polyolefin molten material extruded from the mold is lower, making it more susceptible to deformation under external forces (extraction force and gravity). (3) The effects of extraction force and gravity result in uneven crystallinity at different locations in the polyolefin material, further promoting warping. In response to some of the above causes of warping, the applicant proposes improvements from several perspectives, including raw material composition, manufacturing molding process, and molding equipment.

[0018] This application aims to modify conventional polyvinyl chloride-based wood-plastic composite molding equipment to adapt it for the production of new non-polyvinyl chloride-based wood-plastic composite materials, thereby solving or mitigating the problem of serious warping deformation of non-polyvinyl chloride-based wood-plastic composite materials caused by the equipment.

[0019] The applicant discovered, through routine experimental procedures, that extrusion equipment significantly affects the crystalline behavior of polyolefin-based non-polyvinyl chloride wood-plastic composite boards. Based on this, the applicant unexpectedly found that after the raw material undergoes melting and plasticization by the extruder, when it is extruded from the mold, the molten material is subjected to gravity, causing a sagging phenomenon in the center of the semi-finished board. At the same time, the semi-finished board is subjected to a horizontal pulling force during the transport process. As a result of the superposition of forces in two different directions, inconsistent changes occur in the crystalline behavior of the center and edges of the semi-finished board. Consequently, the degree of crystallinity and crystal size differ between the center and edges of the semi-finished board, ultimately resulting in warping in the width direction.

[0020] This application addresses the phenomenon by providing an ingenious modification to create a narrow angle between the die's output port and the horizontal plane. As a result, the angle between the direction in which the semi-finished sheet material is taken along the output port by the take-up roll unit and the direction of gravity acting on the semi-finished sheet material itself becomes less than 90 degrees. With the above configuration, the combined force of the take-up force of the take-up roll unit and gravity in the thickness direction of the semi-finished sheet material is weakened and distributed more uniformly in the width direction of the semi-finished sheet material, thereby reducing the warping of the semi-finished sheet material in the width direction.

[0021] Furthermore, the above configuration improves the resultant force along the length of the semi-finished sheet material, thereby causing the polymer or microcrystalline structure inside the semi-finished sheet material to undergo a clear orientation along the length. This further accelerates the longitudinal induction of the semi-finished sheet material by external forces, ultimately improving the crystallization rate and degree of crystallinity of the semi-finished sheet material. As a result, shrinkage and warping caused by changes in crystal type are prevented during the subsequent cooling and storage processes.

[0022] Furthermore, the structure of polymers or microcrystals within the semi-finished sheet material is induced by the action of external forces to undergo orientation, and as a result, the crystal structure is always uniformly aligned in a certain direction along the length of the semi-finished sheet material, the mechanical strength, hardness, and wear resistance of the semi-finished sheet material can be significantly improved.

[0023] However, it is not the case that the smaller the angle between the direction in which the semi-finished plate is pulled by the take-up roll unit along the discharge outlet and the direction of gravity applied to the semi-finished plate itself, the better. For example, under the extreme condition where the two directions overlap, the resultant force along the length direction of the semi-finished plate increases significantly, which may cause the phenomenon that the thickness of the semi-finished plate becomes uneven, specifically resulting in flow lines or wavy lines on the surface.

[0024] Therefore, to summarize the above, by changing the angular relationship between the discharge outlet of the mold and the horizontal plane, the present application changes the included angle between the direction in which the semi-finished plate is pulled by the take-up roll unit along the discharge outlet and the direction of gravity applied to the semi-finished plate itself, effectively overcoming the problems of shrinkage and warpage that did not occur in the conventional extrusion process of plate base materials using polyvinyl chloride as raw material. At the same time, the mechanical strength, hardness and wear resistance of the plate are additionally improved unexpectedly.

[0025] Preferably, the take-up roll unit comprises at least an input take-up roll pair for pulling the semi-finished plate along the inclined direction of the discharge outlet, and an output take-up roll pair for conveying the semi-finished plate along the horizontal direction.

[0026] Since the take-up roll unit in the present application comprises a plurality of take-up roll pairs, multiple times of pressing and forming can be performed on the semi-finished plate during the take-up process, thereby microscopically controlling the crystal state inside the semi-finished plate, ensuring that the crystal size structure inside the semi-finished plate is maintained in a substantially uniform state, and preventing problems such as warpage caused by differences in the crystal state of various parts.

[0027] Preferably, the included angle between the perpendicular line of the center connecting line of the two take-up rolls in the input take-up roll pair and the horizontal plane is larger than the included angle between the discharge outlet and the horizontal plane.

[0028] By providing the above-mentioned limitations in the present application, the take-up rolls of the input take-up roll pair can be brought into a state nearly perpendicular to the horizontal plane, and thus a larger take-up force can be applied. This is conducive to more effectively taking up the semi-finished plate material, provides a stronger tensile force, and improves the stability of the plate material during the conveyance process. At the same time, the inclined input take-up roll pair can take up the semi-finished plate material by inclining it along the direction of the output port. Such a take-up method can improve the conveyance of the plate material, allow the plate material to pass through the apparatus more smoothly, and reduce possible galling and clogging that may occur. In addition, since the take-up force applied by the input take-up roll pair is large, it can effectively resist the gravity applied to the semi-finished plate material. This can reduce the risk of deformation of the plate material during the conveyance process and maintain the shape stability of the plate material. Finally, the inclined input take-up roll pair can better control the movement trajectory and speed of the semi-finished plate material. This can improve the operation efficiency of the production line and ensure that the semi-finished plate material is conveyed and processed in a scheduled manner.

[0029] Preferably, a center connecting line of the input take-up roll pair and a center connecting line of the output take-up roll pair intersect each other and are not perpendicular to each other.

[0030] In this application, by having the center connecting lines of the input take roll pair and the output take roll pair intersect but not perpendicular, the following advantages may be obtained: (1) Intersecting and non-perpendicular center connecting lines can guide the direction change of the semi-finished sheet material during the take process. This improves the conveying path of the sheet material, allows it to pass through the device more smoothly, and reduces the possibility of galling or jamming. (2) Intersecting center connecting lines help to apply the take force uniformly and distribute it evenly across the entire surface of the sheet material. This reduces the risk of deformation of the sheet material and contributes to maintaining the stability of the sheet material during the conveying process. (3) Because the center connecting lines intersect but are not perpendicular, the input take roll pair and the output take roll pair can cooperate better and provide stronger tensile and take forces. This improves the take effect and allows for better control of the semi-finished sheet material. (4) The design of intersecting and non-perpendicular center connecting lines can provide more operational flexibility. The operator can adjust the angle between the input and output take-up roll pairs as needed to meet the requirements of different sheet materials.

[0031] Preferably, the input take-up roll pair includes a pair of take-up rolls arranged vertically, and the height of the mold's output port is greater than the height of the take-up rolls located below the input take-up roll pair.

[0032] By setting the output port height higher than the height of the lower take roll of the input take roll pair, it is possible to ensure that semi-finished sheet metal passes smoothly through the take rolls. This prevents the semi-finished sheet metal from getting jammed or obstructed by the take rolls during the transport process, ensuring smooth transport of the sheet metal, reducing the possibility of jamming and production stoppages, and improving the production capacity and efficiency of the production line. In addition, it is possible to avoid damage and deformation of the semi-finished sheet metal during the transport process, reducing the frequency of maintenance and replacement of the take rolls. This reduces maintenance costs and extends the lifespan of the take rolls. At the same time, it is possible to avoid excessive pressure and deformation on the semi-finished sheet metal when passing through the take rolls. This helps maintain the integrity of the shape and structure of the sheet metal and reduces the risk of potential damage.

[0033] Preferably, the semi-finished sheet material output from the output port is taken up and conveyed along the tangential direction of the input take-up roll pair.

[0034] By taking in and transporting semi-finished sheet metal along the tangential direction of the input take-up roll pair, stable motion can be achieved. This take-up method reduces shaking and impact on the sheet metal during the transport process, ensuring stable transport of the sheet metal, and allowing the sheet metal to pass through the equipment at a faster and more stable speed, thereby improving the production capacity and efficiency of the production line. Furthermore, by taking in and transporting semi-finished sheet metal in the tangential direction, the position and placement of the sheet metal can be better controlled. This contributes to improved processing and positioning accuracy of the sheet metal, ensuring that the quality and dimensions of the final product meet requirements. In addition, this take-up method allows for the uniform application of take-up force, reducing the risk of bending and deformation of the sheet metal during the transport process and avoiding localized deformation of the sheet metal, thus maintaining the flatness and shape stability of the sheet metal.

[0035] Preferably, the angle between the output port and the horizontal plane is 30 to 60°.

[0036] Preferably, the temperature of the take-up roll unit is lower than the temperature of the output port, and the temperature of the take-up rolls in the take-up roll unit increases sequentially along the direction of transport of the semi-finished sheet material.

[0037] This application describes how to control the crystalline behavior of polymers during the transport process of semi-finished sheet materials by providing a temperature gradient. As the molten raw material is discharged along the output port of the mold, the temperature of the surface of the semi-finished sheet material decreases rapidly, but the central part remains at a high temperature. As a result, a large temperature difference exists between the inside and outside of the semi-finished sheet material, causing a clear change in the crystallinity of the inside and outside of the semi-finished sheet material. Specifically, the particle size of polymer crystals on the surface of the semi-finished sheet material becomes smaller, while the polymer crystals inside the semi-finished sheet material become relatively larger. At the same time, due to the rapid decrease in temperature on the surface of the semi-finished sheet material, some polymer chains are cooled and fixed before they can crystallize, causing a change in the degree of polymer crystallinity between the inside and outside of the semi-finished sheet material, which in turn further affects the stability of the semi-finished sheet material.

[0038] To address the aforementioned problems, this application proposes influencing the polymer crystallization process by setting the temperature of the take-up roll unit. The applicant has found that by using a take-up roll unit with gradually increasing temperature, the degree of crystallization inside and outside the semi-finished sheet material can be increased, improving the crystallinity of the polymer and enabling precise control over the polymer crystallization process. This ensures that uniform crystallization is obtained during the conveying process, improving product quality and consistency, and reducing material non-uniformity. This contributes to improving the strength and rigidity of the semi-finished sheet material, making it more suitable for specific application requirements. Furthermore, by gradually increasing the temperature of the take-up rolls in the take-up roll unit, an annealing process can be performed on the semi-finished sheet material, reducing residual stress in the semi-finished sheet material. The principle is that temperature changes promote the rearrangement of polymer molecules, reducing residual stress in the sheet material and improving the stability and durability of the sheet material.

[0039] In summary, by setting the temperature of the take-up roll unit lower than the temperature of the output port, and gradually increasing the temperature of the take-up roll along the conveying direction of the semi-finished sheet material, it is possible to control the crystalline behavior of the polymer, improve the strength of the semi-finished sheet material, reduce residual stress, and improve the quality and consistency of the product.

[0040] Preferably, in the take-up roll unit, the temperature difference between the take-up roll for inputting semi-finished sheet material and the temperature of the output port is 10 to 15°C, and the temperature difference between the take-up roll for outputting semi-finished sheet material and the temperature of the output port is 10°C or less.

[0041] In this application, by making the temperature of the take-up rolls of the take-up roll unit and the temperature of the semi-finished sheet material output from the output port relatively close, it is possible to effectively avoid the non-uniformity of crystals caused by the rapid cooling of the semi-finished sheet material, thereby further improving the stability of the semi-finished sheet material and reducing its warping rate.

[0042] Preferably, the take-up roll includes a take-up roll body and a first temperature control jacket covering the outside of the take-up roll body, and the inside of the first temperature control jacket is filled with a temperature control liquid capable of controlling the surface temperature of the first temperature control jacket.

[0043] This application describes a design in which the take-up roll includes a take-up roll body and an external first temperature control jacket, and by filling the jacket with a temperature control fluid capable of controlling the surface temperature, precise control and optimization of the take-up roll temperature can be achieved through effects such as temperature control, temperature uniformity, heat quantity adjustment, and adhesion prevention.

[0044] Preferably, a temperature control device for controlling the temperature of the semi-finished sheet material output from the output port of the mold is provided on the outside of the output port.

[0045] Preferably, the temperature control device includes a second temperature control jacket, and the inside of the second temperature control jacket is filled with a temperature control fluid.

[0046] Preferably, the deformation control device further includes a support base for supporting the take-up roll unit, the support base further provided with a drive device for driving and moving the take-up rolls in the take-up roll unit.

[0047] The presence of a support base provides the necessary support and stability for the take-up roll unit. The support base supports the entire weight of the take-up roll unit, ensuring balance and stability during operation. Simultaneously, the movement of the take-up roll can be precisely controlled via the drive mechanism. This enables precise take-up and positioning of semi-finished sheet materials, ensuring accuracy in product dimensions and shape.

[0048] Preferably, a shaping template for shaping semi-finished sheet metal is further provided behind the pull-up roll unit on the support base.

[0049] Standard templates can provide precise, fixed shapes and dimensions. By bringing semi-finished sheet metal into contact with the standard template and applying appropriate pressure and heat sources, it is possible to ensure that the semi-finished sheet metal is formed into the desired shape and dimensions according to the design requirements during the shaping process, thereby improving the shaping accuracy of the product. At the same time, using standard templates can reduce shaping deviations caused by manual inconsistencies, improving product consistency and stability, and increasing production efficiency.

[0050] Preferably, the deformation control device further includes a mold hanger for suspending and securing the mold.

[0051] Mold hangers provide a safe and reliable method for lifting and securing molds. They ensure stability during the lifting and transport process, preventing accidental shaking or dropping, and protecting the safety of equipment and operators. They also simplify the mold lifting and securing process, improving lifting efficiency and accuracy.

[0052] In a second aspect, the present invention also provides an extrusion production line for non-polyvinyl chloride wood-plastic composite boards, the line comprising a deformation control device for non-polyvinyl chloride wood-plastic composite boards as described in any one of the above paragraphs.

[0053] Preferably, the extrusion production line for the non-polyvinyl chloride wood-plastic composite board material is provided with an extruder, a deformation control device, a cooling mechanism, a take-up mechanism, and a cutting mechanism in sequence along the material transport direction.

[0054] In this application, the extruder is the starting point of the production line and is used to heat, melt, and extrude non-PVC wood-plastic composite material into a sheet. A deformation control device is located after the extruder and is used to control the deformation of the extruded sheet material, thereby reducing the problem of warping after extrusion. A cooling mechanism is used to rapidly cool and solidify the extruded sheet material to maintain the desired shape and dimensions. A take-up mechanism is located after the cooling mechanism and is used to take up and stretch the cooled sheet material to increase its strength and stability. A cutting mechanism is located after the take-up mechanism and is used to cut the cooled and taken-up sheet material to the desired length to obtain the final non-PVC wood-plastic composite sheet product.

[0055] With the above production line configuration, extrusion production of non-PVC wood-plastic composite boards can be realized, and the role of the deformation control device in this process is to control the deformation of the extruded board to obtain the desired shape and dimensions.

[0056] Preferably, the cooling device includes a plurality of driven cooling rolls and a plurality of driven cooling rolls.

[0057] A cooling system using driven and driven cooling rolls can improve production efficiency. Rapid cooling and deformation control increase the cooling rate of extruded sheet metal, shortening the production cycle. At the same time, uniform cooling and shape control reduce the defect rate of sheet metal caused by temperature inconsistencies and shape deformation, improving product quality and production capacity.

[0058] Preferably, the cooling device further includes a cooling bracket provided behind the driven cooling roll and the driven cooling roll.

[0059] Preferably, the bottom of the deformation control device and cooling mechanism is provided with a guide rail arranged along the extension direction of the extruder, and the bottom of the deformation control device and cooling mechanism is further provided with a pulley for moving the deformation control device and cooling mechanism along the guide rail to control the distance from the mold.

[0060] The design of the guide rails and pulleys enables flexible adjustment of the deformation control device and cooling mechanism. By adjusting the position of the pulleys, the operator can control the distance between the deformation control device and cooling mechanism and the mold, allowing it to be adapted to molds of different sizes and shapes. At the same time, by adjusting the position of the pulleys, the gap between the deformation control device and cooling mechanism and the mold can be fine-tuned to achieve the desired deformation and cooling effects. Furthermore, the design of the guide rails and pulleys makes the adjustment and maintenance of the deformation control device and cooling mechanism easier. The operator can easily move the deformation control device and cooling mechanism for cleaning, repair, or parts replacement. This reduces downtime and improves the stability and reliability of the production line. Finally, by quickly adjusting the distance between the deformation control device and cooling mechanism and the mold, mold changeover and adjustment times can be shortened, reducing production line downtime and improving production efficiency and capacity.

[0061] As a third aspect, the present invention also provides applications of a deformation control device for non-polyvinyl chloride wood-plastic composite boards, or an extrusion production line for non-polyvinyl chloride wood-plastic composite boards including the deformation control device, in the manufacture of non-polyvinyl chloride wood-plastic composite boards or non-polyvinyl chloride flooring.

[0062] The present invention has the following beneficial effects: -The deformation control device for non-polyvinyl chloride wood-plastic composite boards in this application changes the angle between the direction in which the semi-finished board is taken up by the take-up roll unit along the output opening and the direction of gravity acting on the semi-finished board itself, thereby effectively overcoming the problems of shrinkage and warping that did not occur in the conventional extrusion process of board substrates made from polyvinyl chloride; - Simultaneously, the above configuration can unexpectedly further improve the mechanical strength, hardness, and wear resistance of the plate material; -In this application, by adding a deformation control device for non-polyvinyl chloride wood-plastic composite boards to the extrusion production line for the non-polyvinyl chloride wood-plastic composite boards, it is possible to avoid rejection of flooring materials due to warping of the boards. [Brief explanation of the drawing]

[0063] [Figure 1] This is a schematic diagram of the structure of the extrusion production line for non-polyvinyl chloride wood-plastic composite board material in the present invention. [Figure 2] This is an enlarged view of part a in Figure 1 of the present invention. [Figure 3] This is a schematic diagram of the lifting structure of the mold of the present invention. [Figure 4] This is a schematic diagram of the structure of the pull-up roll unit of the present invention. [Figure 5] This is a schematic diagram of the cross-sectional structure of the take-up roll of the present invention. [Figure 6] This is a schematic diagram of the cross-sectional structure of the mold of the present invention. [Figure 7] This is a schematic diagram of the structure of the mold temperature controller in the cooling mechanism of the present invention. [Explanation of symbols]

[0064] Extruder 100, barrel 101, feeding mechanism 102, semi-finished sheet material 200, mold 300, output port 301, temperature control device 302, second temperature control jacket 303, mold hanger 304, take-up roll unit 400, take-up roll 401, No. 1 take-up roll 401-1, No. 2 take-up roll 401-2, No. 3 take-up roll 401-3, input take-up roll pair 402, output take-up roll pair 403, take-up roll body 404, first temperature control jacket 405, support base 406, drive device 407, standard template 408, cooling mechanism 500, mold temperature controller 501, driven cooling roll 502, driven cooling roll 503, cooling bracket 504, guide rail 505, pulley 506, take-up mechanism 600, cutting mechanism 700. [Modes for carrying out the invention]

[0065] The present invention will be further described below with reference to specific examples. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the examples of the present invention mentioned in the following descriptions are usually only a part of the present invention, not all examples. Accordingly, all other examples that those skilled in the art can obtain based on the examples of the present invention without expending any creative effort are within the scope of the protection of the present invention.

[0066] As shown in Figure 1, this embodiment 1 provides an extrusion production line for non-polyvinyl chloride wood-plastic composite boards. Along the material transport direction (i.e., from left to right in Figure 1), the extrusion production line sequentially includes an extruder 100 for melting and plasticizing a non-polyvinyl chloride material and extruding the molten body after plasticization, a mold 300 for outputting the molten body after plasticization to form a semi-finished board 200, a take-up roll unit 400 for taking up the semi-finished board 200 and controlling its deformation rate, a cooling mechanism 500 for cooling and shaping the semi-finished board 200 after deformation control, a take-up mechanism 600 for taking up the semi-finished board 200, and a cutting mechanism 700 for cutting the semi-finished board 200 to obtain a finished non-polyvinyl chloride wood-plastic composite board.

[0067] Here, the extruder 100 is either a single-screw or twin-screw extruder and includes a barrel 101 and a feeding mechanism 102 for supplying material into the barrel 101. Taking the production of polypropylene-based wood-plastic composite boards as an example, first, the raw materials for the polypropylene-based wood-plastic composite boards are fed into the feeding mechanism 102. These raw materials are heated by the barrel 101 and plasticized by the internal screw, then melted to form a molten material. Typically, the raw materials for the polypropylene-based wood-plastic composite boards contain polypropylene resin and wood flour, and in some cases, a certain amount of plasticizer and lubricant. After mixing these raw materials, the desired raw materials for the polypropylene-based wood-plastic composite boards are obtained by crushing them in an extrusion granulation facility or a kneader.

[0068] As shown in Figures 2 and 3, the mold 300 is connected to the end of the barrel 101 and includes one output port 301. The molten material flowing out of the barrel 101 is extruded through the output port 301 to become a semi-finished sheet material 200. Unlike conventional sheet material substrates made from polyvinyl chloride, such as SPC substrates and LVT substrates, the mold 300 in this application has a certain narrow angle with respect to the horizontal plane. As a result, the semi-finished sheet material 200 output from the mold 300 is output in a non-horizontal direction, suppressing an increase in the warping rate of the semi-finished sheet material 200 due to gravity.

[0069] Because the mold 300 is heavy, in some preferred embodiments, a mold hanger 304 is specially added to lift and secure the mold 300 in order to enhance the connection stability between the mold 300 and the barrel 101. This provides a safe and reliable method for lifting and securing the mold 300. This ensures the stability of the mold 300 during the lifting and transport process, avoids unexpected shaking or falling, and protects the safety of the equipment and operators. At the same time, it simplifies the mold lifting and securing process and improves the efficiency and accuracy of the lifting.

[0070] As shown in Figures 2 and 4, in order to fit the mold 300, this embodiment further includes a set of take-up roll units 400 for taking up and shaping the semi-finished sheet material 200 behind the mold 300, and the take-up roll unit 400 is obtained by combining a plurality of take-up rolls 401. As shown in Figure 2, there are three take-up rolls 401 in this embodiment, and these three take-up rolls 401 can be divided into take-up roll 1 401-1, take-up roll 2 401-2, and take-up roll 3 401-3 along the conveying direction of the semi-finished sheet material. According to the classification based on the position and function of the take-up rolls 401, the take-up rolls 401 within the take-up roll unit 400 can be divided into, at least, an input take-up roll pair 402 consisting of a No. 1 take-up roll 401-1 and a No. 2 take-up roll 401-2 for taking up the semi-finished sheet material 200 along the inclined direction of the output port 301, and an output take-up roll pair 403 consisting of a combination of a No. 2 take-up roll 401-2 and a No. 3 take-up roll 401-3 for changing the transport direction of the semi-finished sheet material 200 and transporting it horizontally.

[0071] In some preferred embodiments, the center connecting lines of the first take-up roll 401-1 and the second take-up roll 401-2 in the input take-up roll pair 402 intersect with, but are not perpendicular to, the center connecting lines of the second take-up roll 401-2 and the third take-up roll 401-3 in the output take-up roll pair 403. As a result, the second take-up roll 401-2 and the third take-up roll 401-3 are aligned horizontally, while the first take-up roll 401-1 and the second take-up roll 401-2 are positioned diagonally in the vertical direction. The first take-up roll 401-1 is closer to the output port 301 of the mold 300 than the second take-up roll 401-2. Also, the height of the output port 301 of the mold 300 is higher than the height of the first take-up roll 401-1 and lower than the height of the second take-up roll 401-2. As a result, the semi-finished sheet material 200 output from the output port 301 is taken up and conveyed tangentially to both the first take-up roll 401-1 and the second take-up roll 401-2.

[0072] In some preferred embodiments, the angle between the perpendicular line connecting the centers of the first take-up roll 401-1 and the second take-up roll 401-2 in the input take-up roll pair 402 and the horizontal plane is greater than the angle between the output port 301 and the horizontal plane. This setting further reduces the degree of warping of the semi-finished sheet metal 200 produced.

[0073] To explore the relationship between the angle between the output port 301 and the horizontal plane and the degree of warping of the final semi-finished sheet metal 200, this embodiment tested the manufactured semi-finished sheet metal 200 with different output port 301 angles and with take-up roll units 400 adapted to each output port 301 angle. The test results are shown in Table 1 below.

[0074] [Table 1]

[0075] As can be seen from the test results above, the effect of gravity on the degree of warping of the semi-finished sheet metal 200 can be effectively reduced by changing the angle of the output port 301. When the output port 301 is parallel to the horizontal plane (i.e., the angle is 0°), the degree of warping of the semi-finished sheet metal reaches its maximum of 0.62 mm / m. As the angle between the output port 301 and the horizontal plane increases, the degree of warping gradually decreases, and when the angle between the output port 301 and the horizontal plane is 30° or more, the degree of warping of the semi-finished sheet metal 200 can reach a level of less than 0.3 mm / m. However, a larger angle between the output port and the horizontal plane is not always better, as when the angle between the output port 301 and the horizontal plane is 80°, flow patterns have already formed on the surface of the semi-finished sheet metal 200, and when the output port 301 is perpendicular to the horizontal plane (i.e., the angle is 90°), significant flow patterns were present. Therefore, considering the degree of warping and the flow pattern of the semi-finished sheet material 200, the manufactured semi-finished sheet material 200 exhibits the best performance when the angle between the output opening 301 and the horizontal plane is 30 to 60°.

[0076] In addition to the fact that the angle between the output port 301 and the horizontal plane has a regulating effect on the warping of the semi-finished sheet material 200, the applicant also discovered that the temperature of each take-up roll 401 in the take-up roll unit has an auxiliary effect on the deformation control of the semi-finished sheet material 200. The applicant found that after the semi-finished sheet material 200 is output along the output port 301, the temperature of its surface rapidly decreases, but the central part still maintains a high temperature. As a result, a large temperature difference exists between the inside and outside of the semi-finished sheet material 200, causing a clear change in the crystallographic performance between the inside and outside of the semi-finished sheet material 200. Specifically, the grain size of the polymer crystals on the surface of the semi-finished sheet material 200 becomes smaller, and the polymer crystals inside the semi-finished sheet material become relatively larger. Furthermore, due to the rapid decrease in temperature on the surface of the semi-finished sheet material 200, some polymer chains are cooled and fixed before they can crystallize, causing a change in the degree of crystallinity of the polymer inside and outside the semi-finished sheet material 200, which in turn further affects the stability of the semi-finished sheet material 200.

[0077] In this embodiment, to address the above-mentioned problems, the crystallization process of the polymer was altered by setting the temperature of the take-up roll unit 400, thereby reducing warping and deformation of the semi-finished sheet material 200 after extrusion. The specific settings are as follows: First, by setting the overall temperature of the take-up roll unit 400 lower than the temperature of the output port 301, the crystallization of the polymer inside the semi-finished sheet material 200 can be promoted. At the same time, the temperature of the take-up roll 401 in the take-up roll unit 400 is gradually increased along the conveying direction of the semi-finished sheet material 200. The gradually increasing temperature of the take-up roll unit 400 increases the degree of crystallization both inside and outside the semi-finished sheet material 200, thereby increasing the degree of polymer crystallization and enabling precise control of the polymer crystallization process. This ensures that uniform crystallization is obtained during the conveying process, thereby improving product quality and consistency and reducing material non-uniformity. This helps to increase the strength and rigidity of the semi-finished sheet material 200, making it more suitable for specific application needs. Furthermore, by gradually increasing the temperature of the take-up roll 401 in the take-up roll unit 400, an annealing process can be performed on the semi-finished sheet material 200, thereby reducing residual stress in the semi-finished sheet material 200. The principle is that the change in temperature promotes the rearrangement of polymer molecules, reducing residual stress in the sheet material and improving the stability and durability of the sheet material.

[0078] In some preferred conditions of this embodiment, the temperature difference between the take roll 401 for inputting the semi-finished sheet material 200 in the take roll unit 400 and the temperature of the output port 301 can be set to 10 to 15°C, and the temperature difference between the take roll 401 for outputting the semi-finished sheet material 200 in the take roll unit 400 and the temperature of the output port 301 can be set to 10°C or less. By setting it in this way, the temperature of the take roll 401 of the take roll unit 400 and the temperature of the semi-finished sheet material 200 output from the output port 301 can be made relatively close, making it possible to effectively avoid the phenomenon of crystalline non-uniformity caused by rapid cooling of the semi-finished sheet material 200, thereby further increasing the stability of the semi-finished sheet material 200 and reducing its warping rate.

[0079] To investigate the relationship between the temperature of the take-up roll unit 400 and the degree of warping of the final semi-finished sheet metal 200, this embodiment conducted tests on semi-finished sheet metal 200 produced at different take-up roll unit 400 temperatures. The test results are shown in Table 2 below.

[0080] [Table 2]

[0081] As can be seen from the test results above, the degree of warping of the final semi-finished sheet material 200 is adjusted accordingly with changes in the temperature of each take-up roll 401 in the take-up roll unit 400.

[0082] This application specifically describes a design for the take-up roll 401 and the mold 300 in order to precisely control the temperature of the take-up roll 401 and the output port 300 in the take-up roll unit 400.

[0083] In some preferred embodiments, as shown in Figure 5, the take-up roll 401 includes a take-up roll body 404 and a first temperature control jacket 405 covering the outside of the take-up roll body 404, and the region between the first temperature control jacket 405 and the take-up roll body 404 is filled with a temperature control fluid capable of controlling the surface temperature of the first temperature control jacket 405.

[0084] As shown in Figure 6, the mold 300 is provided with a temperature control device 302 on the outside of the output port 301 for controlling the temperature of the semi-finished sheet material 200 output from the output port 301. The temperature control device 302 includes a second temperature control jacket 303, and the inside of the second temperature control jacket 303 is filled with a temperature control liquid.

[0085] Furthermore, as shown in Figures 1 and 2, in order to enhance the support and stability required for the take-up roll unit 400, this embodiment further includes a support base 406 for supporting the take-up roll unit 400, and a drive device 407 for driving and moving the take-up rolls 401 in the take-up roll unit 400 is provided on the support base 406. The drive device 407 may be a motor or other device for providing rotational power to the take-up rolls 401, and one drive device 407 may be provided corresponding to each take-up roll 401, or one drive device 407 may be provided corresponding to multiple take-up rolls 401, and the interlocking of multiple take-up rolls 401 may be achieved via a transmission device (e.g., a transmission belt or a transmission chain).

[0086] Furthermore, in order to further enhance the stability of the semi-finished sheet metal 200, this embodiment provides a shaping template 408 for shaping the semi-finished sheet metal 200 behind the take-up roll unit 400 on the support base 406. The shaping template 408 is in contact with the semi-finished sheet metal 200 and can be subjected to a constant pressure and heat source, thereby applying a constant thermal pressure effect to the semi-finished sheet metal, which ensures that the semi-finished sheet metal is formed into the desired shape and dimensions according to the design requirements during the shaping process, thereby improving the shaping accuracy of the product.

[0087] The cooling mechanism 500 includes a mold temperature controller 501 equipped with rolls, the schematic diagram of which is shown in Figure 7. The mold temperature controller 501 includes multiple sets of driven cooling rolls 502 and multiple sets of driven cooling rolls 503, and after the semi-finished sheet material 200 comes out of the shaping template 408, it is sequentially conveyed forward along the driven cooling rolls 502 and driven cooling rolls 503, and is rapidly cooled and shaped through contact between the driven cooling rolls 502 and driven cooling rolls 503 and the semi-finished sheet material 200.

[0088] As shown in Figure 1, after the semi-finished sheet metal 200 exits the mold temperature controller 501, it enters a cooling bracket 504. As the semi-finished sheet metal 200 moves on the cooling bracket 504, it comes into contact with air, thereby cooling and lowering its temperature.

[0089] In some preferred embodiments, to facilitate adjustment of the distance between the take-up roll unit 400, cooling mechanism 500 and the mold 300, the applicant provides a guide rail 505 at the bottom of the take-up roll unit 400 and cooling mechanism 500, which is provided along the extension direction of the extruder 100. Furthermore, a pulley 506 is provided at the bottom of the take-up roll unit 400 and cooling mechanism 500, which is compatible with the guide rail 505, allowing the take-up roll unit 400 and cooling mechanism 500 to move along the guide rail 505 and control the distance to the mold. This allows the operator to control the distance between the take-up roll unit 400 and cooling mechanism 500 and the mold 300 by adjusting the position of the pulley 506 on the guide rail 505, and to adapt to molds 300 of different dimensions and shapes. At the same time, by adjusting the position of the pulley 506, the gap between the take-up roll unit 400 and cooling mechanism 500 and the mold can be fine-tuned to achieve the desired deformation and cooling effects.

[0090] To ensure reliable collection of the semi-finished sheet material 200, a collection mechanism 600 driven by a motor or other drive mechanism is provided behind the cooling bracket 504. This mechanism inputs the semi-finished sheet material 200 into a cutting mechanism 700 located behind the collection mechanism 600, thereby cutting the semi-finished sheet material 200 and ultimately obtaining a finished non-polyvinyl chloride wood-plastic composite sheet material.

[0091] In this application, by changing the angular relationship between the output port 301 of the mold 300 and the horizontal plane, the angle between the direction in which the semi-finished sheet material 200 is taken up by the take-up roll unit 400 along the output port 301 and the direction of gravity acting on the semi-finished sheet material 200 itself is changed, effectively overcoming the problems of shrinkage and warping that did not occur in the conventional extrusion process of sheet material substrates made from polyvinyl chloride. At the same time, unexpectedly, it was possible to further improve the mechanical strength, hardness, and wear resistance of the sheet material. Furthermore, in this application, by adding a deformation control device for non-polyvinyl chloride wood-plastic composite sheet material to the extrusion production line of the non-polyvinyl chloride wood-plastic composite sheet material, it is possible to avoid an increase in the rejection rate of flooring material caused by warping of the sheet material.

[0092] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art can make various modifications, additions, or substitutions to the described embodiments without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A deformation control device for non-polyvinyl chloride wood / plastic composite boards, It comprises a die fixedly connected to an extruder for outputting semi-finished sheet material, and a take-roll unit composed of a combination of multiple take-rolls for taking and shaping the semi-finished sheet material, The mold includes an output port for outputting the semi-finished sheet material, A narrow angle exists between the output port and the horizontal plane. A deformation control device for non-polyvinyl chloride wood / plastic composite boards, characterized in that the direction in which the semi-finished board material is taken up by the take-up roll unit along the output port does not overlap with the direction of gravity acting on the semi-finished board material itself, and the angle between the two is less than 90 degrees.

2. The deformation control device for non-polyvinyl chloride wood / plastic composite boards according to claim 1, characterized in that the take-up roll unit includes at least an input take-up roll pair for taking up the semi-finished board material along the inclined direction of the output port, and an output take-up roll pair for transporting the semi-finished board material along the horizontal direction.

3. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 2, characterized in that the angle between the perpendicular line connecting the centers of the two take-up rolls in the input take-up roll pair and the horizontal plane is greater than the angle between the output port and the horizontal plane.

4. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 2, characterized in that the center connecting line of the input take-up roll pair and the center connecting line of the output take-up roll pair intersect each other but are not orthogonal to each other.

5. The aforementioned input take-up roll pair includes a pair of take-up rolls arranged vertically, A deformation control device for non-polyvinyl chloride wood / plastic composite board material according to any one of claims 2, 3, or 4, characterized in that the height of the output port of the mold is higher than the height of the take-up roll located below the input take-up roll pair.

6. A deformation control device for non-polyvinyl chloride wood / plastic composite board material according to any one of claims 1 to 4, characterized in that the semi-finished board material output from the output port is taken up and conveyed along the tangential direction of the input take-up roll pair.

7. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 1, characterized in that the angle between the output port and the horizontal plane is 30 to 60°.

8. The temperature of the take-up roll unit is lower than the temperature of the output port, and The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 1, characterized in that the temperature of the take-up roll in the take-up roll unit increases sequentially along the conveying direction of the semi-finished board material.

9. In the aforementioned take-up roll unit, the temperature difference between the take-up roll for inputting the semi-finished sheet material and the temperature of the output port is 10 to 15°C. The deformation control device for non-polyvinyl chloride wood / plastic composite boards according to claim 8, characterized in that the difference between the temperature of the take-up roll for outputting the semi-finished board material and the temperature of the output port in the take-up roll unit is 10°C or less.

10. The aforementioned take-up roll includes a take-up roll body and a first temperature control jacket covering the outside of the take-up roll body. A deformation control device for non-polyvinyl chloride wood / plastic composite board material according to any one of claims 1, 8, or 9, characterized in that the inside of the first temperature control jacket is filled with a temperature control liquid capable of controlling the surface temperature of the first temperature control jacket.

11. A deformation control device for non-polyvinyl chloride wood-plastic composite board material according to any one of claims 1, 8, or 9, characterized in that a temperature control device for controlling the temperature of the semi-finished board material output from the output port is provided outside the output port of the mold.

12. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 11, characterized in that the temperature control device includes a second temperature control jacket, and the inside of the second temperature control jacket is filled with a temperature control liquid.

13. The deformation control device further comprises a support base for supporting the take-up roll unit, The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 1, characterized in that the support base is further provided with a drive device for driving and moving the take-up roll in the take-up roll unit.

14. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 13, characterized in that a shaping template for shaping the semi-finished board material is further provided behind the take-up roll unit on the support base.

15. The deformation control device for non-polyvinyl chloride wood / plastic composite board material according to claim 1 or 13, further comprising a mold hanger for suspending and fixing the mold.

16. An extrusion production line for non-polyvinyl chloride wood-plastic composite boards, An extrusion production line for non-polyvinyl chloride wood-plastic composite boards, characterized by including a deformation control device for non-polyvinyl chloride wood-plastic composite boards as described in any one of claims 1 to 15.

17. An extrusion production line for non-polyvinyl chloride wood-plastic composite board material according to claim 16, characterized by comprising an extruder, the deformation control device, a cooling mechanism, a take-up mechanism, and a cutting mechanism, which are sequentially installed along the material transport direction.

18. The extrusion production line for non-polyvinyl chloride wood-plastic composite boards according to claim 17, characterized in that the cooling mechanism includes a plurality of sets of driven cooling rolls and a plurality of sets of driven cooling rolls.

19. The extrusion production line for non-polyvinyl chloride wood-plastic composite boards according to claim 18, characterized in that the cooling mechanism further includes a cooling bracket installed behind the driven cooling roll and the driven cooling roll.

20. Guide rails are provided at the bottom of the deformation control device and the cooling mechanism, and are installed along the extension direction of the extruder. An extrusion production line for non-polyvinyl chloride wood-plastic composite board material according to any one of claims 17, 18, or 19, further characterized in that a pulley is provided at the bottom of the deformation control device and the cooling mechanism for moving the deformation control device and the cooling mechanism along the guide rail to control the distance from the mold.

21. Use of a deformation control device for non-polyvinyl chloride wood-plastic composite boards according to any one of claims 1 to 15, or an extrusion production line for non-polyvinyl chloride wood-plastic composite boards including the deformation control device according to any one of claims 16 to 20, in the manufacture of non-polyvinyl chloride wood-plastic composite boards or non-polyvinyl chloride flooring.

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