A continuous fiber reinforced polyurethane foaming mold and foaming molding method

Abstract

The present invention belongs to the technical field of polyurethane rigid foam reinforcement, and specifically relates to a continuous fiber reinforced polyurethane foam mold and a foaming molding method, comprising an upper mold and a lower mold with a mold cavity, the lower mold being located on both sides of the mold cavity and having a yarn threading portion 1 for continuous fibers to pass through, the lower mold being located on both sides of the mold cavity with the yarn threading portion 1 and having external inserts provided thereon, the external inserts being provided with a yarn threading portion 2 for continuous fibers to pass through, the external inserts being movable on the lower mold so that the yarn threading portion 2 is misaligned with the yarn threading portion 1, so as to fix the continuous fibers through the external inserts and seal the yarn threading portion 1. The present invention allows continuous fibers to pass in and out of the mold and keeps the continuous fibers in a straight and evenly distributed state in the mold cavity, while also ensuring the airtightness requirements of the mold cavity during foam molding and ensuring the molding quality of the product. The mold structure is simple, the product molding method is simple, and the research and development costs of continuous fiber reinforced polyurethane rigid foam products are reduced. Moreover, the product is not limited to the traditional rectangular shape and is more designable.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane rigid foam reinforcement, and particularly relates to a continuous fiber reinforced polyurethane foaming mould and a foaming molding method. Background Art

[0002] Rigid polyurethane foam (PURF) boasts excellent properties such as lightweight, thermal insulation, moisture resistance, sound insulation, heat resistance, shock absorption, and corrosion resistance. It is widely used in construction, refrigeration, transportation, packaging, and other fields. However, compared with other materials, PURF's mechanical properties, such as flexural strength and compressive strength, are relatively low, limiting its widespread use. In recent years, research on the reinforcement of PURF has become a hot topic.

[0003] Currently, research on the reinforcement of polyurethane rigid foam focuses primarily on particle reinforcement and fiber reinforcement. Particle reinforcement primarily includes silica particles, calcium carbonate, and hollow glass microspheres, while fiber reinforcement primarily includes chopped glass fiber and long glass fiber. However, both particle and chopped fiber reinforced polyurethane have limited improvement in the mechanical properties of polyurethane rigid foam. The only method that can truly significantly improve the mechanical properties of polyurethane rigid foam is continuous fiber reinforcement, and polyurethane foam synthetic sleepers fall into this category. Because polyurethane rigid foam has significant application value in multiple fields, in-depth research on continuous fiber reinforcement is essential to obtain polyurethane rigid foam with better performance.

[0004] At present, the industry generally adopts injection molding and pultrusion systems for continuous fiber reinforced polyurethane foam, which can meet the continuous production needs of products. However, the overall molding process is complex and the required equipment is large. For example, the laminator in the pultrusion system is generally up to 30 meters long. Therefore, when using such a system to conduct research on continuous fiber reinforced polyurethane rigid foam, the equipment investment and research costs are very high. In addition, although the structure of traditional polyurethane foam molds is relatively simple, they are closed cavities and cannot be applied to continuous fiber reinforced polyurethane foam research. This is mainly because the closed cavity cannot realize continuous fiber threading. If the cut continuous fiber is directly laid in, it cannot be guaranteed that the continuous fiber will be straight and evenly distributed in the mold cavity after dipping. The quality of the obtained product is extremely poor, and the research value and data reference value are low. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a continuous fiber reinforced polyurethane foam mold and foaming molding method. The continuous fibers can be passed into and out of the mold and maintained in a straight, evenly distributed state within the mold cavity. Furthermore, the airtightness requirements of the mold cavity during foaming molding can be guaranteed, thereby ensuring the quality of the product molding. The mold has a simple structure, is convenient to use, and is easy to operate. At the same time, the product molding process is simple and can be well applied to the research and development of continuous fiber reinforced polyurethane rigid foam products, reducing the cost of research and development products. Furthermore, the product is not limited to traditional rectangular shapes and is more designable.

[0006] The present invention provides a continuous fiber reinforced polyurethane foaming mold, comprising an upper mold and a lower mold with a cavity, the upper mold is used to close the cavity, the lower mold is located on both sides of the cavity and has a yarn threading portion 1 for continuous fibers to pass through, and the lower mold is located on both sides of the cavity with the yarn threading portion 1 and has external inserts arranged outside, the external inserts are provided with a yarn threading portion 2 for continuous fibers to pass through, and the external inserts can be moved on the lower mold so that the yarn threading portion 2 is misaligned with the yarn threading portion 1, so that the continuous fibers can be fixed by the external inserts and the yarn threading portion 1 is closed.

[0007] Furthermore, the outer insert moves in the height direction of the cavity to fix the continuous fiber through the misalignment of the yarn threading part 2 and the yarn threading part 1, and when fixing the continuous fiber, the position of the yarn threading part 2 in the height direction of the cavity is lower than that of the yarn threading part 1. When the upper mold closes the cavity, the outer insert is located below the upper mold.

[0008] Furthermore, a chamfer is provided on a lower side of one end of the yarn threading portion 1 facing the yarn threading portion 2 and / or an upper side of one end of the yarn threading portion 2 facing the yarn threading portion 1.

[0009] Furthermore, the first yarn threading portion and the second yarn threading portion are both provided with at least two rows along the height direction of the cavity.

[0010] Furthermore, the first yarn threading portion and the second yarn threading portion are holes or through slots.

[0011] Furthermore, the lower mold is detachably provided with inner inserts on both sides of the cavity, and the yarn threading part is opened on the inner insert. The side of the inner insert facing the inside of the cavity forms the inner wall of the cavity on that side, and the outer insert is arranged on the side of the inner insert away from the cavity.

[0012] Furthermore, the lower mold is provided with limiting steps on both sides of the inner insert, the inner insert is placed on the lower mold, and the limiting steps limit the inner insert in the direction toward the inside of the cavity. The two ends of the outer insert are connected to the lower mold through positioning grooves arranged along the height direction of the cavity, and the outer insert limits the inner insert in the direction away from the cavity.

[0013] Furthermore, a disassembly groove is provided between the bottom of the outer insert and the lower mold.

[0014] Furthermore, it also includes a clamping device for locking the upper mold and the lower mold after the upper mold closes the cavity.

[0015] The present invention also provides a continuous fiber reinforced polyurethane foaming molding method, using the continuous fiber reinforced polyurethane foaming mold as described above, the foaming molding method comprising the following steps:

[0016] S1. Adjust the position of the outer insert so that the yarn threading part 2 is aligned with the yarn threading part 1, and pass the continuous fiber through the yarn threading part 1 and the yarn threading part 2 on one side of the cavity, and pass it out from the yarn threading part 1 and the yarn threading part 2 on the other side of the cavity;

[0017] S2. Injecting the prepared polyurethane foam resin into the cavity and allowing the continuous fibers to be fully soaked in the polyurethane foam resin;

[0018] S3, moving the outer insert to displace the yarn threading part 2 from the yarn threading part 1 to fix the continuous fiber and close the yarn threading part 1, and then closing the cavity through the upper mold;

[0019] S4, heating, foaming and curing, and then demoulding.

[0020] The beneficial effect of the present invention is that the foaming mold of the present invention is based on the arrangement of the yarn threading part 1, the outer insert and the yarn threading part 2, and by adjusting the position of the outer insert, the yarn threading part 2 is aligned with the yarn threading part 1, and the continuous fiber is inserted into the yarn threading part 1 and the yarn threading part 2 on one side of the cavity and is inserted out of the yarn threading part 1 and the yarn threading part 2 on the other side of the cavity, and the continuous fiber is in a state of being laterally inserted into the cavity, and the movement of the outer insert is used to displace the yarn threading part 2 and the yarn threading part 1, so that the area between the continuous fiber and the yarn threading part 1 and the yarn threading part 2 is pressed by the abutment of the yarn threading part 1 and the yarn threading part 2 in opposite directions for fixation, so that the continuous fiber can be in a straight state in the cavity after being impregnated with the polyurethane foam resin and during foaming, and effectively plays a continuous reinforcement effect after foaming. The cavity is open on the lower mold, which is convenient for injecting the polyurethane foam resin into the cavity and convenient for fully impregnating the continuous fiber with the polyurethane foam resin manually or with the help of other tools.

[0021] Compared with the method of using an external insert without the yarn threading part 2 to directly press down the continuous fiber to fix it, the present invention, on the basis of achieving the fixation of the continuous fiber, does not need to leave a gap between the external insert and the side with the yarn threading part 1 to avoid the bending of the continuous fiber. Therefore, the gap is smaller, and only a conventional assembly gap is required. When the yarn threading part 2 is misaligned with the yarn threading part 1, the position of the external insert outside the yarn threading part 2 can effectively block the hollow part of the yarn threading part 1 to seal it. Combined with the continuous fiber threaded in the yarn threading part 1, the overall closure of the yarn threading part 1 is achieved. After the upper mold is closed, a closed space is formed in the mold cavity, which meets the sealing requirements of foaming molding, can avoid the leakage of polyurethane foam resin during foaming and affect the molding quality of the product, ensure the acquisition of products with good performance uniformity, and provide effective reference value for subsequent research.

[0022] Compared to the pultrusion system, the present invention does not require complex molding equipment such as glue injection and pultrusion to complete the development of continuous fiber reinforced polyurethane rigid foam products. The overall structure is simple, the processing difficulty and cost are lower, the operation is convenient, and the molding process is simple. It can be better applied to the research and development of continuous fiber reinforced polyurethane rigid foam products, reducing the cost of research and development products. And based on the structural setting of the foaming mold of the present invention, the inner diameter requirements of the threading part one and the threading part two can be relaxed. On the basis of achieving fixed continuous fibers, ensuring that the state and distribution of the continuous fibers in the cavity meet the requirements and avoiding the leakage of polyurethane foam resin, the threading operation of the continuous fibers is simpler and more convenient, and can be applied to the threading of different amounts of continuous fibers under different reinforcement requirements. In addition, on the basis of realizing the development of continuous fiber reinforced polyurethane rigid foam products, the shape of the product is not limited by the traditional pultrusion process. By setting the cavity to a rectangle or an arc, a rectangular or arc-shaped product can be correspondingly formed. The designability of the product is stronger and meets the product development needs of different reinforcement requirements and shapes. In some small-scale production lines, where there are large restrictions on production costs, the foaming mold of the present invention can also be used for small-scale production of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of the continuous fiber reinforced polyurethane foaming mold of the present invention.

[0024] Figure 2 For the present invention Figure 1 A magnified view of the structure in Figure 2.

[0025] Figure 3 It is a structural schematic diagram of the inner insert of the present invention.

[0026] Figure 4 It is a structural schematic diagram of the outer insert of the present invention.

[0027] Figure 5This is a schematic diagram of the alignment state of the second yarn threading part and the first yarn threading part on the lower mold of the present invention.

[0028] Figure 6 This is a schematic diagram of the misaligned state of the second and first yarn threading parts on the lower mold according to the present invention.

[0029] Figure 7 For the present invention Figure 6 A magnified view of the structure at point B in FIG.

[0030] Figure 8 This is a schematic structural diagram of the continuous fiber reinforced polyurethane foaming mold of the present invention after removing the inner and outer inserts.

[0031] Figure 9 For the present invention Figure 5 Schematic diagram of the arc-shaped cavity from the perspective.

[0032] In the figure: 1. Upper mold; 2. Lower mold; 21. Limiting step; 22. Positioning groove; 23. Disassembly groove; 3. Cavity; 4. Inner insert; 41. Yarn threading part 1; 5. Outer insert; 51. Yarn threading part 2; 52. Chamfer; 53. Positioning boss; 6. Locking device; 7. Handle. DETAILED DESCRIPTION

[0033] like Figures 1-9 As shown, the present invention provides a continuous fiber reinforced polyurethane foaming mold, which includes an upper mold 1 and a lower mold 2 with a cavity 3. The upper mold 1 is used to be arranged on the top of the lower mold 2 to close the cavity 3. The lower mold 2 is located on both sides of the cavity 3 and is provided with a threading portion 41 for continuous fiber to pass through. The lower mold 2 is located on both sides of the cavity 3 where the threading portion 41 is opened. External inserts 5 are provided outside the lower mold 2 on both sides of the cavity 3 where the threading portion 41 is opened. That is, the lower mold 2 is located on each side of the cavity 3 where the threading portion 41 is opened. The external inserts 5 are provided with a threading portion 2 51 for continuous fiber to pass through. The external inserts 5 can be moved on the lower mold 2 so that the position of the threading portion 2 51 relative to the threading portion 1 41 can be changed, and the threading portion 2 51 can be aligned or misaligned with the threading portion 1 41 to fix the continuous fiber and close the threading portion 1 41. The continuous fibers refer to fibers that are continuous as a whole, not short-cut or sticky fibers, and the yarn threading portion 1 41 and the yarn threading portion 2 51 may be hole or groove structures.

[0034] The foaming mold of the present invention is based on the setting of the yarn threading part 1 41, the outer insert 5 and the yarn threading part 2 51. By adjusting the position of the outer insert 5, the yarn threading part 2 51 is aligned with the yarn threading part 1 41, and the continuous fiber is passed through the yarn threading part 1 41 and the yarn threading part 2 51 on one side of the cavity 3, and passed out from the yarn threading part 1 41 and the yarn threading part 2 51 on the other side of the cavity 3. The continuous fiber is in a state of being horizontally inserted in the cavity 3, and the movement of the outer insert 5 is used to make the yarn threading part 2 51 and the yarn threading part 1 41 misaligned, so that the area between the continuous fiber between the yarn threading part 1 41 and the yarn threading part 2 51 is pressed by the abutment of the yarn threading part 1 41 and the yarn threading part 2 51 in opposite directions for fixation, so that the continuous fiber can be straightened and evenly distributed in the cavity 3 after being impregnated with the polyurethane foaming resin and during foaming, thereby ensuring the molding quality of the product. The cavity 3 is set in an open shape on the lower mold 2, which makes it easy to inject polyurethane foam resin into the cavity 3 and facilitate manual or other tools to fully impregnate the continuous fiber with the polyurethane foam resin. The full impregnation specifically means that the part of the continuous fiber located in the cavity 3 is completely impregnated with the aforementioned resin.

[0035] Compared with the method of directly pressing down the continuous fiber to fix it by using the outer insert 5 without the yarn threading portion 2 51, the present invention, on the basis of fixing the continuous fiber, does not need to leave a gap between the outer insert 5 and the side with the yarn threading portion 1 41 to avoid the bending of the continuous fiber, so the gap is smaller, and only a conventional assembly gap is required. When the yarn threading portion 2 51 and the yarn threading portion 1 41 are misaligned, the position of the outer insert 5 outside the yarn threading portion 2 51 can effectively block the hollow part of the yarn threading portion 1 41 to seal it, and because the polyurethane foam resin has It has a certain viscosity and poor fluidity. It will not leak out under the condition of conventional assembly gap, and it is difficult to automatically and completely infiltrate the continuous fiber and flow out along the continuous fiber. Therefore, after covering the hollow part of the threading part 41, the threading part 41 is combined with the continuous fiber passed through the threading part 41 to achieve the overall closure of the threading part 41. After the upper mold 1 is closed, a closed space is formed in the cavity 3, which meets the sealing requirements of foaming molding, can avoid the leakage of polyurethane foaming resin during foaming and affect the molding quality of the product, ensure the acquisition of products with good performance uniformity, and provide effective reference value for subsequent research.

[0036] Compared to the pultrusion system, the present invention does not require complex molding equipment such as glue injection and pultrusion to complete the development of continuous fiber reinforced polyurethane rigid foam products. The overall structure is simple, the processing difficulty and cost are lower, the operation is convenient, and the molding process is simple. It can be better applied to the research and development of continuous fiber reinforced polyurethane rigid foam products, reducing the cost of research and development products. Based on the structural setting of the foaming mold of the present invention, the inner diameter requirements of the threading portion 1 41 and the threading portion 2 51 can be relaxed. On the basis of achieving the fixing of the continuous fiber, ensuring that the state and distribution of the continuous fiber in the cavity 3 meet the requirements and avoiding the leakage of the polyurethane foam resin, the threading operation of the continuous fiber is simpler and more convenient, and can be applied to the threading of different amounts of continuous fiber under different reinforcement requirements. In addition, on the basis of realizing the development of continuous fiber reinforced polyurethane rigid foam products, the shape of the product is not limited by the traditional pultrusion process. By setting the cavity to a rectangle or an arc, a rectangular or arc-shaped product can be correspondingly formed. The product is more designable and meets the product development needs of different reinforcement requirements and shapes. In some small-scale production lines, where there are large restrictions on production costs, the foaming mold of the present invention can also be used for small-scale production of products.

[0037] In a preferred embodiment of the present invention, the outer insert 5 is moved in the height direction of the cavity 3 to fix the continuous fiber by the misalignment of the threading portion 2 51 and the threading portion 1 41, and when fixing the continuous fiber, the threading portion 2 51 is misaligned with the threading portion 1 41 in the height direction of the cavity 3, and the position of the threading portion 2 51 in the height direction of the cavity 3 is lower than the threading portion 1 41, that is, the outer insert 5 is preferably moved downward to achieve misalignment fixation. When the upper mold 1 closes the cavity 3, the outer insert 5 is located below the upper mold 1, and the position of the outer insert 5 can be fixed by the pressure applied downward after the upper mold 1 is closed, which can eliminate the need for fasteners and further simplify the overall structure of the foaming mold. When the outer insert 5 moves in other directions along the cavity 3, such as moving along the width direction of the cavity 3 or moving upward along the height direction of the cavity 3, the position of the outer insert 5 can be fixed by fasteners such as bolts.

[0038] In the embodiment in which the outer insert 5 is moved downward to achieve dislocation fixation, a chamfer 52 is provided on the lower side of one end of the yarn threading portion 1 41 toward the yarn threading portion 2 51 and / or on the upper side of one end of the yarn threading portion 2 51 toward the yarn threading portion 1 41. When the yarn threading portion 1 41 and the yarn threading portion 2 51 are dislocated, the chamfer 52 can effectively compress the continuous fiber, and when the continuous fiber is compressed downward and generates a certain degree of bending, the gap between the outer insert 5 and the side where the yarn threading portion 1 41 is provided will not be enlarged, and the gap can still be maintained as a conventional assembly gap, which can effectively prevent the polyurethane foam resin from leaking while effectively fixing the continuous fiber, thereby ensuring the reliability of product molding and the stability of product molding quality. In the embodiment in which the outer insert 5 is moved in other directions, the position of the chamfer 52 is provided at the position where the ends of the yarn threading portion 1 41 and the yarn threading portion 2 51 will come into contact with the continuous fiber after movement.

[0039] The yarn threading sections 1 41 and 2 51 are each provided in at least two rows along the height direction of the cavity 3 to meet the requirement for the distribution of the continuous fibers in the height direction of the cavity 3. The yarn threading sections 1 41 in different rows and the yarn threading sections 2 51 in different rows can be staggered to improve the uniformity of the distribution of the continuous fibers. In the present invention, the number of yarn threading sections 1 41 and yarn threading sections 2 51 in a single row can preferably be multiple to ensure the uniformity of the distribution of the continuous fibers in the cavity 3, thereby ensuring the uniformity of the distribution of the continuous fibers in the product.

[0040] Preferably, the yarn threading part 1 41 and the yarn threading part 2 51 are both holes. When the yarn threading part 1 41 and the yarn threading part 2 51 are provided with at least two rows, the staggered arrangement can still ensure that all continuous fibers threaded therethrough are effectively fixed and the leakage of polyurethane foam resin is effectively avoided, thereby ensuring the stability of the product molding quality while ensuring the uniform distribution of the continuous fibers in the product.

[0041] The shapes of the yarn threading portion 1 41 and the yarn threading portion 2 51 are determined according to actual design requirements. When there are multiple yarn threading portions 1 41 and 2 51 in a single row, each yarn threading portion 1 41 and each yarn threading portion 2 51 can be a hole of any shape, such as a waist-shaped hole, a circular hole, an elliptical hole, or a polygonal hole. When there are one or two yarn threading portions 1 41 and 2 51 in a single row, each yarn threading portion 1 41 and each yarn threading portion 2 51 can be a through slot of any shape, such as a rectangular through slot. The specific arrangement and number of yarn threading portions 1 41 and 2 51 can vary according to actual design requirements and are not limited to a single one here.

[0042] The lower mold 2 is provided with detachable inner inserts 4 on both sides of the cavity 3. The yarn threading portion 41 is specifically provided on the inner inserts 4. The side of the inner inserts 4 facing the interior of the cavity 3 forms the inner wall of the cavity 3 on that side. The outer inserts 5 are provided on the side of the inner inserts 4 facing away from the cavity 3. The provision of the detachable inner inserts 4 can facilitate demoulding of the product after foaming and curing.

[0043] The inner insert 4 is detachably arranged as follows: both sides of the inner insert 4 are provided with a limiting step 21. The inner insert 4 is placed on the lower mold 2. The limiting step 21 limits the inner insert 4 in the direction toward the interior of the cavity 3. In order to ensure the reliable positioning of the inner insert 4 in this direction, the lower mold 2 is provided with two limiting steps 21 for limiting the position of a single inner insert 4. The two limiting steps 21 respectively limit the two ends of the single inner insert 4. The two ends of the outer insert 5 are inserted into the lower mold 2 through positioning grooves 22 provided along the height direction of the cavity 3. On the one hand, it can ensure the stability of the outer insert 5 when it is placed on the lower mold 2. On the other hand, the outer insert 5 can limit the inner insert 4 in the direction away from the cavity 3, thereby fixing the position of the inner insert 4. After the outer insert 5 is pulled out, the inner insert 4 can be directly removed. This arrangement can eliminate the need for additional locking parts, reduce the complexity of the overall structure of the foaming mold, and improve the convenience of the subsequent demolding operation.

[0044] Among them, the arrangement of the outer panel 5 can be as follows: the positioning groove 22 is opened on the lower mold 2 along the height direction of the cavity 3, and two positioning grooves 22 corresponding to a single outer panel 5 are provided on the lower mold 2, and the two ends of the single outer panel 5 are directly inserted into the two positioning grooves 22, or the two ends of the outer panel 5 are provided with positioning bosses 53, and the positioning bosses 53 at both ends of the single outer panel 5 are inserted into the two positioning grooves 22. It can also be as follows: the positioning groove 22 is opened on the two ends of the outer panel 5 along the height direction of the cavity 3, and the lower mold 2 is provided with positioning bosses 53 along the height direction of the cavity 3, and two positioning bosses 53 corresponding to a single outer panel 5 are provided on the lower mold 2, and the positioning grooves 22 at both ends of the single outer panel 5 are plugged into and matched with the two positioning bosses 53.

[0045] A disassembly groove 23 is provided between the bottom of the outer insert 5 and the lower mold 2. The disassembly groove 23 is specifically provided on the lower mold 2. The outer insert 5 can be lifted upwards manually or with the help of a tool through the disassembly groove 23 to facilitate the removal of the outer insert 5. Preferably, both ends of the outer insert 5 and the inner insert 4 are provided with a draft angle to facilitate the removal of the outer insert 5 and the inner insert 4.

[0046] In the present invention, the two sides of the cavity 3 on which the inner insert 4 and the outer insert 5 are provided are opposite to each other. When the cavity 3 is of other shapes or when the distribution requirements for the continuous fibers are different, the two sides of the cavity 3 on which the inner insert 4 and the outer insert 5 are provided can be adjacent to each other, or the cavity 3 can have more than three sides provided with the inner insert 4 and the outer insert 5, which can be determined according to the actual product design requirements. In the present invention, the cavity 3 has two inserts on one side, namely the inner insert 4 and the outer insert 5. When the requirements for the fixation of the continuous fibers are different, other inserts with yarn threading portions can also be provided on the side of the outer insert 5 away from the inner insert 4, that is, more than three inserts are provided on one side of the cavity 3, so that the continuous fibers are fixed on one side of the cavity 3 by the mutual dislocation of more than three inserts.

[0047] like Figure 9 The figure shows an embodiment in which the cavity 3 is arc-shaped. The cavity 3 is provided with inner and outer inserts 4 and 5 on either side of the arc. In this embodiment, the side of the upper mold 1 facing the lower mold 2 has a shape that matches the top of the lower mold 2, ensuring a good fit and seal after the molds are closed. When using this embodiment, after the continuous fibers are threaded and fixed, the polyurethane foam resin is poured in. Because the polyurethane foam resin has a certain viscosity and poor fluidity, after the continuous fibers are kneaded to completely saturate the polyurethane foam resin, the resin essentially adheres to the continuous fibers and does not flow downward or outward along the cavity. After the molds are closed and heated for foaming and curing, the resin foam expands the continuous fibers and fills the cavity, ensuring a uniform distribution of the continuous fibers.

[0048] In the present invention, the upper mold 1 is hingedly mounted on one side of the lower mold 2. The present invention also includes a clamping device 6 for locking the upper mold 1 and the lower mold 2 after the upper mold 1 seals the mold cavity 3. The structure of the clamping device 6 is conventional and will not be described in detail here. The upper mold 1 is provided with a grid of venting grooves to prevent molding defects caused by poor venting. Handles 7 are also provided on both sides of the lower mold 2 to facilitate lifting the entire foaming mold.

[0049] In a preferred embodiment of the present invention, the outer panel 5 is fixed in a dislocated manner by moving downward, and the position of the outer panel 5 is fixed by the pressure applied downward after the upper mold 1 is closed. When the top of the outer panel 5 moves downward and there is a large height difference between the top of the inner panel 4 and the top of the inner panel 4, a stop boss matching the shape of the outer panel 5 can be set in the area of ​​the upper mold 1 corresponding to the position of the outer panel 5 to ensure that the outer panel 5 can be pressed and fixed during the closing of the mold. In a preferred embodiment of the present invention, the height of the outer panel 5 and the inner panel 4 are set differently, and the area on the lower mold 2 for arranging the inner panel 4 and the outer panel 5 is set to a height difference to ensure that the top of the outer panel 5 is substantially flush with the top of the inner panel 4 after moving downward. In the case that the upper mold 1 is plate-shaped, the outer panel 5 can also be effectively pressed. In this preferred embodiment, if there is a certain height difference between the top of the outer panel 5 and the top of the inner panel 4 after moving downward due to too little continuous fiber penetration, the height difference can also be compensated by adding a gasket between the bottom of the outer panel 5 and the lower mold 2.

[0050] The present invention also provides a continuous fiber reinforced polyurethane foaming molding method, using the continuous fiber reinforced polyurethane foaming mold as described above, the foaming molding method comprising the following steps:

[0051] S1. Adjust the position of the outer insert 5 so that the second threading portion 51 is aligned with the first threading portion 41. Insert the continuous fiber through the first threading portion 41 and the second threading portion 51 on one side of the cavity 3 and pass it out through the first threading portion 41 and the second threading portion 51 on the other side of the cavity 3.

[0052] S2. Injecting the prepared polyurethane foam resin into the cavity 3 and fully impregnating the continuous fibers with the polyurethane foam resin, that is, allowing the area of ​​the continuous fibers located in the cavity 3 to be completely impregnated with the polyurethane foam resin;

[0053] S3, move the outer insert 5 to displace the yarn threading portion 2 51 and the yarn threading portion 1 41 to fix the continuous fiber and close the yarn threading portion 1 41, and close the cavity 3 through the upper mold 1;

[0054] S4, heating, foaming and curing, and then demoulding.

[0055] This foaming molding method is simple in process and requires no complex molding equipment such as glue injection or pultrusion. It can complete the development of continuous fiber-reinforced polyurethane rigid foam products. The overall structure is simple, and the processing difficulty and cost are lower. Furthermore, based on the structural arrangement of the foaming mold of the present invention, while achieving the goal of fixing the continuous fibers, ensuring that the state and distribution of the continuous fibers within the mold cavity 3 meet the requirements, and preventing leakage of the polyurethane foam resin, it can be adapted to thread different amounts of continuous fibers to meet different reinforcement requirements. This product has strong designability and meets the development needs of products with different reinforcement requirements.

[0056] Wherein, before step S1, it also includes cleaning the cavity 3 and spraying a release agent in the cavity 3. In step S1, after all the continuous fibers are threaded, the two ends of all the continuous fibers are respectively tied and tightened on the outside of the foaming mold to facilitate subsequent simultaneous grasping of all the continuous fibers. In step S2, all the continuous fibers in the cavity 3 are fully impregnated with the polyurethane foam resin by manual kneading, or all the continuous fibers are fully impregnated with the polyurethane foam resin by other means such as mechanical vibration, ultrasonic microwaves, etc. In step S3, manually hold or clamp the two ends of all the continuous fibers after the bundle is tightened with the help of other tools, so that the continuous fibers are in a state of being pulled toward both ends, and then move the outer insert 5 to dislocate the threading portion 2 51 and the threading portion 1 41 to achieve fixation of the continuous fibers. In step S3, the upper mold 1 and the lower mold 2 are locked by the clamping device 6. Step S4 is specifically as follows: placing the foaming mold in an oven or a molding machine for heating, foaming and curing. After curing is completed, the mold is taken out and the product is demolded; the demolding process is: after loosening the locking device 6, the upper mold 1 is opened, and the outer insert 5 is loosened through the disassembly groove 23, and then the outer insert 5, the inner insert 4 and the entire product are taken out in turn, and then the continuous fibers on the periphery are cut off, and the outer insert 5 and the inner insert 4 are knocked out along the yarn direction.

[0057] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0058] The one or more embodiments of this application are intended to encompass all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this application should be included in the scope of protection of this application.

Claims

1. A continuous fiber reinforced polyurethane foaming mold, characterized in that: The invention comprises an upper mold (1) and a lower mold (2) with a mold cavity (3), wherein the upper mold (1) is used to close the mold cavity (3), and the lower mold (2) is provided with a threading portion (41) for continuous fiber to pass through on both sides of the mold cavity (3), and an outer insert (5) is provided on both sides of the mold cavity (3) with the threading portion (41), and the outer insert (5) is provided with a threading portion (51) for continuous fiber to pass through on the outer insert (5), and the outer insert (5) can be moved on the lower mold (2) so that the threading portion (51) is misaligned with the threading portion (41), so that the continuous fiber can be fixed by the outer insert (5) and the threading portion (41) is closed; The outer insert (5) can be moved in the height direction of the cavity (3) to fix the continuous fiber by misaligning the second threading portion (51) and the first threading portion (41), and when fixing the continuous fiber, the position of the second threading portion (51) in the height direction of the cavity (3) is lower than that of the first threading portion (41), and when the upper mold (1) closes the cavity (3), the outer insert (5) is located below the upper mold (1); The threading portion 1 (41) is provided with a chamfer (52) on the lower side of one end of the threading portion 2 (51) and / or on the upper side of one end of the threading portion 2 (51) towards the threading portion 1 (41); the threading portion 1 (41) and the threading portion 2 (51) are both provided with at least two rows along the height direction of the cavity (3); the threading portion 1 (41) and the threading portion 2 (51) are holes or through slots; The lower mold (2) is provided with detachable inner inserts (4) on both sides of the mold cavity (3); a yarn threading portion (41) is provided on the inner insert (4); the side of the inner insert (4) facing the inside of the mold cavity (3) forms the inner wall of the mold cavity (3) on that side; and the outer insert (5) is provided on the side of the inner insert (4) facing away from the mold cavity (3).

2. The continuous fiber reinforced polyurethane foaming mold according to claim 1, characterized in that: The lower mold (2) is provided with limiting steps (21) on both sides of the inner insert (4), the inner insert (4) is placed on the lower mold (2), and the limiting steps (21) limit the inner insert (4) in the direction toward the inside of the cavity (3). The two ends of the outer insert (5) are inserted into the lower mold (2) through positioning grooves (22) provided along the height direction of the cavity (3), and the outer insert (5) limits the inner insert (4) in the direction away from the cavity (3).

3. The continuous fiber reinforced polyurethane foaming mold according to claim 2, characterized in that: A disassembly groove (23) is provided between the bottom of the outer insert (5) and the lower die (2).

4. The continuous fiber reinforced polyurethane foaming mold according to any one of claims 1 to 3, characterized in that: It also includes a mold locking device (6) for locking the upper mold (1) and the lower mold (2) after the upper mold (1) closes the mold cavity (3).

5. A continuous fiber reinforced polyurethane foaming molding method, characterized in that: Using the continuous fiber reinforced polyurethane foaming mold according to any one of claims 1 to 4, the foaming molding method comprises the following steps: S1. Adjust the position of the outer insert (5) so that the second threading portion (51) is aligned with the first threading portion (41), and pass the continuous fiber through the first threading portion (41) and the second threading portion (51) on one side of the cavity (3), and pass it out from the first threading portion (41) and the second threading portion (51) on the other side of the cavity (3); S2, injecting the prepared polyurethane foam resin into the mold cavity (3), and allowing the continuous fibers to be fully impregnated with the polyurethane foam resin; S3, moving the outer insert (5) to displace the second threading portion (51) from the first threading portion (41) to fix the continuous fiber and close the first threading portion (41), and closing the cavity (3) through the upper mold (1); S4, heating, foaming and curing, and then demoulding.

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