A prepreg molding method and a molding apparatus thereof

Abstract

The application discloses a prepreg forming method and a forming device thereof, and the prepreg forming method comprises the following steps: producing an intermediate prepreg; obtaining fiber collimation based on width change of a detection area; cutting off an edge area and the detection area on the intermediate prepreg to obtain a prepreg product. The intermediate prepreg comprises the edge area, the detection area and a main body area arranged in sequence along the width direction, the edge area and the main body area are both prepared by resin matrix and reinforcing fibers, the detection area fills the interval between the edge area and the main body area along the width direction, and the width of the detection area is the interval between two reinforcing fibers connected with the detection area respectively in the edge area and the main body area. By arranging the edge area and the detection area and separating the edge area and the main body area from the detection area through the reinforcing fibers, the clear reinforcing fiber edge can be formed on the surface of the prepreg, the detection part can directly observe and measure the data, and the fiber collimation of the prepreg in the prepreg forming process is detected on line.

Description

Technical Field

[0001] This invention relates to the field of composite material technology, and in particular to a prepreg molding method and molding apparatus. Background Technology

[0002] Prepreg is a material in which reinforcing fibers are impregnated in a resin system. As an important intermediate in resin-based composites, it has wide applications in the field of composite materials. Fiber straightness characterizes the neatness and orientation of the reinforcing fibers in the prepreg, directly affecting the mechanical properties of the composite product. Fibers with high straightness can better transfer stress, improve the mechanical and structural properties of the prepreg, and avoid abnormalities such as fiber splitting and clumping during prepreg laying. However, there is currently a lack of methods for online detection of fiber straightness during prepreg production. Summary of the Invention

[0003] To overcome the problems existing in related technologies, the present invention provides a prepreg molding method and molding apparatus.

[0004] According to a first aspect of the present invention, a prepreg molding method is provided, the prepreg molding method being capable of online detection of the fiber straightness of the prepreg, the prepreg molding method comprising:

[0005] Producing intermediate prepreg, the intermediate prepreg comprising an edge region, a detection region, and a main body region arranged sequentially along the width direction of the intermediate prepreg, wherein the detection region fills the gap between the edge region and the main body region in the width direction, and both the edge region and the main body region are made of a resin matrix and reinforcing fibers composite;

[0006] The fiber collimation is obtained based on the width change of the detection area, where the width of the detection area is the distance between the two reinforcing fibers that are respectively connected to the detection area in the edge area and the main body area.

[0007] The edge area and the detection area are cut off from the intermediate prepreg to obtain the prepreg product.

[0008] In some embodiments, the detection area comprises only a resin matrix.

[0009] In some embodiments, the production of the intermediate prepreg includes:

[0010] Provides first reinforcing fiber and second reinforcing fiber;

[0011] The threading plate is divided into a first hole area, a second hole area, and a third hole area, which are arranged along the width direction.

[0012] The first reinforcing fiber is threaded through the first hole area to form the edge area, the second reinforcing fiber is threaded through the second hole area to form the main body area, and no threading is performed on the third hole area;

[0013] The width of the detection area is the distance between the first reinforcing fiber and the second reinforcing fiber that are respectively connected to the detection area.

[0014] In some embodiments, obtaining the fiber collimation based on the width change of the detection area includes:

[0015] Width detection is performed on multiple detection intervals in the detection area to obtain multiple detection results. The multiple detection intervals are arranged sequentially along the length direction of the intermediate prepreg.

[0016] The fiber collimation is obtained by calculating the average of multiple test results;

[0017] The width detection includes:

[0018] The width of the detection area is measured at a first detection position and a second detection position, respectively. The first detection position and the second detection position are located at the two ends of the detection area in the length direction, and the first detection position and the second detection position are separated by a preset length.

[0019] Calculate the absolute value of the width difference of the detection area at the first detection position and the second detection position;

[0020] Based on the absolute value of the width difference and the preset length, the width change of the detection area per unit length is determined, and the width change per unit length is used as the detection result.

[0021] In some embodiments, the detection intervals are connected end to end in sequence along the length direction.

[0022] In some embodiments, the preset lengths of each of the detection intervals are equal; and / or,

[0023] The preset length is 0.8-1.5m.

[0024] In some embodiments, the step of cutting off the edge region and the detection region from the intermediate prepreg to obtain a prepreg product includes:

[0025] Based on the target width of the prepreg product, the intermediate prepreg is divided into a cutting area and a product area, wherein the cutting area includes at least the edge area and the detection area;

[0026] The intermediate prepreg is cut along the boundary of the cutting area, and the cut product area is used as the prepreg product.

[0027] According to a second aspect of the present invention, a prepreg forming apparatus is provided, the prepreg forming apparatus being capable of online detection of the fiber straightness of the prepreg, the prepreg forming apparatus comprising:

[0028] The production department is used to produce intermediate prepreg, which includes an edge region, a detection region, and a main body region arranged sequentially along the width direction of the intermediate prepreg. In the width direction, the detection region fills the gap between the edge region and the main body region. Both the edge region and the main body region include a resin matrix and reinforcing fibers.

[0029] The detection unit is used to detect the width change of the detection area to obtain the fiber alignment. The width of the detection area is the distance between the two reinforcing fibers that are respectively connected to the detection area in the edge area and the main body area.

[0030] A cutting section is used to cut off the edge area and the detection area from the intermediate prepreg to obtain a prepreg product.

[0031] In some embodiments, the detection unit includes an edge detector and a detection control center. The edge detector has the function of acquiring the edges of two reinforcing fibers that are respectively connected to the detection area in the edge region and the main body region. The detection control center is used to calculate and output the fiber collimation based on the edges.

[0032] In some embodiments, the cutting section includes a cutting blade and an adjustment assembly, the adjustment assembly being used to adjust the position and orientation of the cutting blade.

[0033] The beneficial effects of this invention are:

[0034] The prepreg molding method provided by this invention adds an edge zone and a detection zone to the intermediate prepreg, and separates the edge zone and the main body zone from the detection zone by reinforcing fibers. This forms a clear edge of reinforcing fibers on the surface of the prepreg, which facilitates direct observation and measurement of data by the detection department. It enables online detection of fiber straightness of the prepreg during the prepreg molding process. Production personnel can adjust process parameters in a timely manner based on the online detection results, which is beneficial for monitoring the prepreg molding process and timely detection of production abnormalities, thereby improving product quality. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a flowchart illustrating a prepreg molding method according to an exemplary embodiment;

[0037] Figure 2 This is a schematic diagram illustrating an intermediate prepreg according to an exemplary embodiment;

[0038] Figure 3 This is a schematic diagram illustrating an intermediate prepreg according to an exemplary embodiment;

[0039] Figure 4 This is a flowchart illustrating step S100 according to an exemplary embodiment;

[0040] Figure 5 This is a schematic diagram illustrating the division of a threading plate according to an exemplary embodiment;

[0041] Figure 6 This is a schematic diagram illustrating the threading of reinforcing fibers according to an exemplary embodiment;

[0042] Figure 7 This is a flowchart illustrating step S200 according to an exemplary embodiment;

[0043] Figure 8 This is a flowchart illustrating width detection according to an exemplary embodiment;

[0044] Figure 9 This is a flowchart illustrating step S300 according to an exemplary embodiment;

[0045] Figure 10 This is a schematic diagram illustrating the cutting and partitioning of an intermediate prepreg according to an exemplary embodiment;

[0046] Figure 11 This is a schematic diagram of a prepreg molding apparatus according to an exemplary embodiment.

[0047] In the diagram: 1-Intermediate prepreg; 11-Edge area; 12-Detection area; 121-Detection section one; 122-Detection section two; 1201-Detection point one; 1202-Detection point two; 1203-Detection point three; 1204-Detection point four; 1205-Detection point five; 1206-Detection point six; 13-Main body area; 14-Cutting area; 15-Product area; 21-Resin matrix; 22-Reinforcing fiber; 221-First reinforcing fiber; 222-Second reinforcing fiber; 3-Threading plate; 31-First hole area; 32-Second hole area; 33-Third hole area. Detailed Implementation

[0048] Currently, the method for detecting fiber straightness inside prepregs is through microscopic observation. However, the reinforcing fibers on the surface of prepregs are densely packed, and the edges of the reinforcing fibers are not obvious, resulting in large observation errors and limitations in observing only microscopic, localized reinforcing fibers. Some patent documents propose methods for tearing long strips of reinforcing fiber bundles from the prepreg to obtain clearer reinforcing fiber edges. However, tearing the reinforcing fiber bundles will damage the integrity of the prepreg and cannot achieve online detection of fiber straightness.

[0049] To address the problems existing in related technologies, embodiments of the present invention provide a prepreg molding method and apparatus. The prepreg molding method includes: producing an intermediate prepreg; obtaining fiber alignment based on the width variation of the detection zone; and cutting off the edge zone and the detection zone from the intermediate prepreg to obtain a prepreg product. The intermediate prepreg includes an edge zone, a detection zone, and a main body zone arranged sequentially along the width direction. Both the edge zone and the main body zone are made of a resin matrix and reinforcing fibers. The detection zone fills the gap between the edge zone and the main body zone in the width direction, and the width of the detection zone is the distance between the two reinforcing fibers connected to the detection zone in the edge zone and the main body zone, respectively. By adding an edge zone and a detection zone to the intermediate prepreg, and separating the edge zone and the main body zone from the detection zone by reinforcing fibers, a clear edge of the reinforcing fibers can be formed on the surface of the prepreg, facilitating direct observation and measurement of data by the detection unit. This enables online detection of the fiber alignment of the prepreg during the prepreg molding process.

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0051] like Figure 1As shown, this embodiment provides a prepreg molding method to detect the fiber straightness of the prepreg online during the prepreg molding process. The prepreg molding method specifically includes the following steps:

[0052] Step S100: Produce intermediate prepreg.

[0053] refer to Figure 2 The intermediate prepreg 1 includes materials along its own width direction ( Figure 2 The edge region 11, detection region 12, and main body region 13 are arranged sequentially in the y-direction shown. In the width direction, the detection region 12 fills the gap between the edge region 11 and the main body region 13, that is, the two ends of the detection region 12 in the width direction are directly connected to the edge region 11 and the main body region 13, respectively. Both the edge region 11 and the main body region 13 are composites made of resin matrix 21 and reinforcing fibers 22. The edge region 11 and the detection region 12 are separated by the reinforcing fibers 22 in the edge region 11 that are directly connected to the detection region 12 (see reference). Figure 2 The first reinforcing fiber 221 shown is used to separate the main body region 13 and the detection region 12 through the reinforcing fiber 22 in the main body region 13 that is directly connected to the detection region 12 (see reference). Figure 2 The second reinforcing fiber 222 is shown.

[0054] In the intermediate prepreg 1, an edge region 11 and a detection region 12 may be provided only on one side of the main body region 13 (see reference). Figure 2 To reduce material waste during subsequent cutting, edge areas 11 and detection areas 12 can be set on both sides of the main body area (see reference). Figure 3 This is to improve the accuracy of fiber straightness test results.

[0055] During the molding process, the edges of the prepreg are often subjected to uneven stress, which seriously affects the neatness and orientation of the reinforcing fibers. Therefore, the detection area 12 can be separated from the edge of the intermediate prepreg 1 by a certain distance. In one example, the width of the edge area 11 can be set to be greater than 4mm, for example, 5mm, to avoid interference with the detection results. The specific value can be set according to the actual production situation and is not limited thereto.

[0056] Step S200: Obtain fiber collimation based on the width change of the detection area.

[0057] Continue to refer to Figure 2Since the edge region 11 and the detection region 12 are separated by reinforcing fibers 22 in the edge region 11 that are directly connected to the detection region 12, and the main body region 13 and the detection region 12 are separated by reinforcing fibers 22 in the main body region 13 that are directly connected to the detection region 12, the width of the detection region 12 is the spacing between the two reinforcing fibers 22 in the edge region 11 and the main body region 13 that are respectively connected to the detection region 12. In the length direction of the intermediate prepreg ( Figure 2 In the x-direction shown, when the two reinforcing fibers 22 are parallel to each other, the width of the detection area 12 remains unchanged. However, when the directions of the two reinforcing fibers 22 are not aligned, the width of the detection area 12 changes. The greater the difference in the directions of the two reinforcing fibers 22, the greater the change in the width of the detection area 12. Therefore, based on the change in the width of the detection area 12, the fiber alignment of the prepreg can be effectively characterized.

[0058] Step S300: Cut off the edge area and inspection area from the intermediate prepreg to obtain the prepreg product.

[0059] Continue to refer to Figure 2 Since the edge region 11 and the detection region 12 in the intermediate prepreg 1 are added for online detection of the fiber straightness of the prepreg, and there are relatively clear reinforcing fiber edges between the edge region 11 and the detection region, and between the main body region 13 and the detection region 12 on the surface of the prepreg, the surface of the intermediate prepreg 1 has obvious partitions and is not suitable as a prepreg product directly. After the fiber straightness of the prepreg is detected in step S200, the edge region 11 and the detection region 12 can be cut off from the intermediate prepreg 1, and the cut main body region 13 can be used as the prepreg product to obtain a prepreg product with good product uniformity and fiber straightness that meets the requirements.

[0060] This prepreg molding method can form clear reinforcing fiber edges on the surface of the prepreg, which facilitates direct observation and measurement of data by the detection unit in the prepreg molding device. It enables online detection of fiber straightness of the prepreg during the prepreg molding process. Production personnel can adjust process parameters in a timely manner based on the online detection results, which is beneficial for monitoring the prepreg molding process and timely detection of production abnormalities, thereby improving product quality.

[0061] In one embodiment, such as Figure 2 and Figure 3 As shown, the detection area 12 only includes the resin matrix 21, avoiding the formation of textures on the surface of the detection area 12 by the reinforcing fibers. This effectively ensures that when measuring the width of the detection area 12, the detection area 12 is within the width direction ( Figure 2 The two ends of the y-direction shown have sufficiently clear edges to avoid interference from reinforcing fibers in the detection area 12.

[0062] In one embodiment, such as Figure 4 As shown, the production of intermediate prepreg 1 (i.e., step S100) specifically includes the following steps:

[0063] Step S110: Provide the first reinforcing fiber and the second reinforcing fiber.

[0064] The first and second reinforcing fibers can be made of the same or different materials, depending on the actual production requirements. In one embodiment, the first and second reinforcing fibers are made of the same material, which helps ensure the accuracy of fiber alignment and avoids the impact of different reinforcing fiber materials on the test results. In another embodiment, the first and second reinforcing fibers are made of different materials, wherein the second reinforcing fiber uses the reinforcing fiber required in the prepreg product, while the first reinforcing fiber can, for example, use a lower-cost reinforcing fiber to improve the economic efficiency of the prepreg.

[0065] Step S120: Divide the threading plate into a first hole area, a second hole area, and a third hole area. The first hole area, the third hole area, and the second hole area are arranged along the width direction.

[0066] In the prepreg production line, after the reinforcing fiber 22 is threaded through the threading plate 3, it is compounded with the resin matrix 21 to form the intermediate prepreg 1. The width direction of the intermediate prepreg 1 is parallel to the width direction of the threading plate 3. Figure 5 The lines shown in the y-direction are parallel to each other. (Reference) Figure 5 The threading plate 3 is divided into a first perforation area 31, a second perforation area 32, and a third perforation area 33, with the first perforation area 31, the third perforation area 33, and the second perforation area 32 arranged along the width direction. The third perforation area 33, located between the first perforation area 31 and the second perforation area 32, includes at least the portion along the thickness direction of the intermediate prepreg 1. Figure 5 A row of holes (in the z-direction shown) is arranged to form an effective separation between the first hole area 31 and the second hole area 32. The specific division areas of the first hole area 31, the second hole area 32 and the third hole area 33 and the number of holes they contain can be set according to the actual production needs of the intermediate prepreg 1, and will not be elaborated here.

[0067] Step S130: The first reinforcing fiber is threaded through the first hole area to form the edge area, the second reinforcing fiber is threaded through the second hole area to form the main body area, and no threading is performed on the third hole area.

[0068] refer to Figure 2 and Figure 6The first reinforcing fiber 221 and the second reinforcing fiber 222 are threaded through the first aperture region 31 and the second aperture region 32, respectively, and combined with the resin matrix to form the edge region 11 and the main body region 13 of the intermediate prepreg 1, respectively. No threading is performed on the third aperture region 33, so that the detection region 12 only includes the resin matrix, separating the edge region 11 from the main body region 13. At this time, the two ends of the detection region 12 in the width direction are directly connected to one of the first reinforcing fibers 221 in the edge region 11 and one of the second reinforcing fibers 222 in the main body region 13, respectively. The distance between the first reinforcing fiber 221 and the second reinforcing fiber 222 is the width of the detection region 12.

[0069] In one embodiment, such as Figure 7 As shown, the fiber collimation detection (i.e., step S200) specifically includes the following steps:

[0070] Step S210: Width detection is performed on multiple detection intervals in the detection area to obtain multiple detection results. The multiple detection intervals are arranged sequentially along the length direction of the intermediate prepreg.

[0071] refer to Figure 2 In the length direction of the intermediate prepreg ( Figure 2 In the x-direction shown, multiple detection intervals are arranged sequentially on detection area 12. For example, as Figure 2 As shown, the detection area 12 includes a first detection interval 121 and a second detection interval 122. In the width direction ( Figure 2 In the y-direction shown, each detection interval completely fills the detection area 12, and the width of the detection interval is the width of the detection area 12. Width detection can be performed once in each detection interval, thus obtaining multiple detection results.

[0072] Among them, such as Figure 8 As shown, width detection specifically includes the following steps:

[0073] Step S211: Measure the width of the detection area at the first detection position and the second detection position respectively. The first detection position and the second detection position are located at the two ends of the detection area in the length direction, and the first detection position and the second detection position are separated by a preset length.

[0074] Continue to refer to Figure 2In the first detection interval 121, detection points 1201 and 1202 are located at the first detection position, and the distance between them is the width of the first detection interval 121 at the first detection position. Similarly, in the second detection interval 122, detection points 1203 and 1204 are located at the first detection position, and the distance between them is the width of the second detection interval 121 at the second detection position. Likewise, in the second detection interval 122, detection points 1203 and 1204 are located at the first detection position, and the distance between them is the width of the second detection interval 122 at the first detection position. Detection points 1205 and 1206 are located at the second detection position, and the distance between them is the width of the second detection interval 122 at the second detection position.

[0075] The width of the detection interval can be measured directly, such as by directly measuring the distance between detection point 1201 and detection point 1202, or indirectly, such as by first measuring the distance between detection point 1201 and detection point 1202 and the same edge of the intermediate prepreg 1, and then subtracting the two distances to obtain the distance between detection point 1201 and detection point 1202. There are no restrictions on this method.

[0076] Step S212: Calculate the absolute value of the width difference between the detection area at the first detection position and the second detection position.

[0077] Continue to refer to Figure 2 Taking the first detection interval 121 as an example, the widths at the first detection position and the second detection position are different, indicating that the directions of the first reinforcing fiber 221 and the second reinforcing fiber 222, which are directly connected to the two ends of the detection area 12 respectively, are inconsistent. The absolute value of the width difference between the first detection position and the second detection position can effectively characterize the directional deviation of the first reinforcing fiber 221 and the second reinforcing fiber 222 in the first detection interval 121.

[0078] Step S213: Based on the absolute value of the width difference and the preset length, determine the width change of the detection area per unit length, and use the width change per unit length as the detection result.

[0079] Continue to refer to Figure 2 Taking the first detection interval 121 as an example, in the length direction ( Figure 2In the x-direction shown, the distance between the first detection position and the second detection position is a preset length. The ratio of the absolute value of the width difference between the first detection position and the second detection position to the preset length is the width change of the first detection interval 121 per unit length. This can effectively characterize the degree of directional deviation of the first reinforcing fiber 221 and the second reinforcing fiber 222, which are directly connected to the two ends of the detection area 12 respectively, in the first detection interval 121, that is, the fiber collimation in the first detection interval 121.

[0080] Step S220: Calculate the average value of multiple test results to obtain the fiber collimation.

[0081] Multiple detection results obtained by performing width detection on multiple detection intervals in detection zone 12 can characterize the fiber straightness in each detection interval. By averaging the detection results in each detection interval, the overall variation of fiber straightness in the length direction can be characterized, thereby realizing online detection of fiber straightness in prepreg.

[0082] In one embodiment, such as Figure 2 As shown, along the length of the intermediate prepreg 1 ( Figure 2 Along the x-direction shown, each detection interval is connected end-to-end sequentially. For example, refer to... Figure 2 The first detection interval 121 is connected to the second detection interval 122, and the second detection position in the first detection interval 121 coincides with the first detection position in the second detection interval 122. This arrangement allows measurement data from one detection position to be used in both detection intervals, significantly reducing the number of measurements required during the detection process and improving efficiency. Furthermore, since the detection intervals are sequentially connected end-to-end, they collectively cover the detection area 12 along their length. This ensures that there are no unmeasured intervals within the detection area 12, thus enhancing the accuracy of the detection results.

[0083] In one embodiment, the preset lengths of each detection interval are equal to facilitate automated detection during the prepreg molding process. In actual production, the detection unit for width detection in the prepreg molding apparatus is typically fixed, while the intermediate prepreg 1 moves along the assembly line of the prepreg molding apparatus at a certain speed. Therefore, the detection unit can be configured to detect the detection area 12 once every fixed time interval, facilitating operator control of the detection process. At this time, the preset lengths of each detection interval are equal, and this preset length is the distance the intermediate prepreg 1 moves during that fixed time interval.

[0084] The selection of the preset length also affects the fiber alignment test results. If the preset length is too large, it is difficult to accurately reflect the fiber alignment, while if the preset length is too small, the tests will be too frequent and the data volume will be too large, placing a heavy burden on the testing department. Therefore, the preset length can be set to 0.8-1.5m, for example, 1m, to better balance the accuracy of the test data and the control of the number of tests.

[0085] In one embodiment, such as Figure 3 As shown, when the main body area 13 is in the width direction ( Figure 2 When detection areas 12 are set on both sides of the y-direction shown, both detection areas 12 can be detected, and the average value is taken as the fiber straightness of the prepreg. This will not be elaborated here.

[0086] In one embodiment, reference continues Figure 3 When the main body area 13 is in the width direction ( Figure 2 When detection areas 12 are respectively set on both sides in the y-direction (as shown), the width of the main body area 13 can also be detected. The width of the main body area 13 refers to the spacing between the second reinforcing fibers 222 located at both ends of the main body area 13 in the width direction. The width of the main body area 13 can also reflect the neatness and directionality of the reinforcing fibers in the prepreg to a certain extent, and can be used to help characterize the fiber straightness of the prepreg. The method for measuring the width change of the main body area 13 can refer to the method for measuring the width change of the detection area 12, and will not be elaborated here.

[0087] In one embodiment, such as Figure 9 As shown, the cutting of the intermediate prepreg (i.e., step S300) specifically includes the following steps:

[0088] Step S310: Based on the target width of the prepreg product, divide the intermediate prepreg into a cutting area and a product area. The cutting area includes at least an edge area and an inspection area.

[0089] Step S320: Cut the intermediate prepreg along the boundary of the cutting area, and use the cut product area as the prepreg product.

[0090] like Figure 10 As shown in the figure, the dashed line is the boundary line between the cutting area 16 and the product area 15. In one example, refer to... Figure 10 The dividing line is located within the main body area 13. In this case, the cutting area 16 includes not only the edge area 11 and the detection area 12, but also a portion of the main body area 13. That is, the product area 15 is contained within the main body area 13, which avoids the edge of the cut product area 15 including part of the detection area 12 and resulting in poor uniformity. In another example (not shown in the attached figure), the dividing line coincides with the edge of the main body area 13, reducing material waste.

[0091] In the width direction of the intermediate prepreg 1 ( Figure 10 In the y-direction shown, the target width of the prepreg product can be set as the width of the product area 15. The portion of the intermediate prepreg 1 excluding the product area 15 is the cutting area 16. By cutting the cutting area 16 from the intermediate prepreg 1 along the boundary line between the cutting area 16 and the product area 15 (i.e., the boundary of the cutting area 16), the product area 15 with dimensions conforming to the target width is obtained, which can be used as the prepreg product required for subsequent production.

[0092] like Figure 11 As shown, this embodiment provides a prepreg molding apparatus capable of executing the prepreg molding method in any of the above embodiments to detect the fiber straightness of the prepreg online during the prepreg molding production process. The prepreg molding apparatus includes a production section, an inspection section, and a cutting section, which can be arranged sequentially along the production line direction of the prepreg molding apparatus.

[0093] The production section is used to produce intermediate prepreg. The intermediate prepreg can be any of the intermediate prepregs described above, comprising an edge region, a detection region, and a main body region arranged sequentially along the width direction of the intermediate prepreg. In the width direction, the detection region fills the gap between the edge region and the main body region. Both the edge region and the main body region include a resin matrix and reinforcing fibers. The detection section is used to detect the width variation of the detection region to obtain fiber alignment. The width of the detection region is the distance between two reinforcing fibers respectively connected to the detection region in the edge region and the main body region. The cutting section is used to cut off the edge region and the detection region from the intermediate prepreg to obtain the prepreg product.

[0094] The prepreg molding apparatus provided in this embodiment can complete the production of intermediate prepreg, the measurement of fiber straightness, and the cutting of intermediate prepreg. It realizes online detection of fiber straightness of prepreg during the prepreg molding process. Production personnel can adjust the process parameters in the prepreg molding apparatus in a timely manner based on the online detection results, which is conducive to monitoring the prepreg molding process and timely detection of production abnormalities, thereby improving product quality.

[0095] In one embodiment, the detection unit includes an edge detector and a detection control center. The edge detector has the function of acquiring the edges of two reinforcing fibers respectively connected to the detection area in the edge region and the main body region. The edge detector can be, for example, a laser detector, an infrared detector, etc., and there is no limitation thereto. The detection control center is connected to the edge detector and can calculate and output the fiber collimation based on the edges of the reinforcing fibers detected by the edge detector. The calculation method of the fiber collimation can be referred to the previous text and will not be repeated here.

[0096] In one embodiment, the cutting section includes cutting blades and an adjusting assembly. The cutting blades are used to cut the intermediate prepreg. At least two cutting blades may be provided, and the orientation of each cutting blade is parallel to that of the others to obtain a prepreg product with a regular shape. The adjusting assembly is used to adjust the position and orientation of the cutting blades so as to flexibly adjust the cutting process according to production needs.

[0097] The embodiments described in this specification are merely examples of implementations of the inventive concept. The scope of protection of this invention should not be considered as limited to the specific forms stated in the embodiments. The scope of protection of this invention also includes equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A method for molding prepreg, characterized in that, The prepreg molding method can detect the fiber straightness of the prepreg online, and the prepreg molding method includes: Producing intermediate prepreg, the intermediate prepreg comprising an edge region, a detection region, and a main body region arranged sequentially along the width direction of the intermediate prepreg, wherein the detection region fills the gap between the edge region and the main body region in the width direction, and both the edge region and the main body region are made of a resin matrix and reinforcing fibers composite; The fiber collimation is obtained based on the width change of the detection area, where the width of the detection area is the distance between the two reinforcing fibers that are respectively connected to the detection area in the edge area and the main body area. The edge area and the detection area are cut off from the intermediate prepreg to obtain the prepreg product; The detection area includes only the resin matrix; The process of obtaining the fiber collimation based on the width change of the detection area includes: Width detection is performed on multiple detection intervals in the detection area to obtain multiple detection results. The multiple detection intervals are arranged sequentially along the length direction of the intermediate prepreg. The fiber collimation is obtained by calculating the average of multiple test results; The width detection includes: The width of the detection area is measured at a first detection position and a second detection position, respectively. The first detection position and the second detection position are located at the two ends of the detection area in the length direction, and the first detection position and the second detection position are separated by a preset length. Calculate the absolute value of the width difference of the detection area at the first detection position and the second detection position; Based on the absolute value of the width difference and the preset length, the width change of the detection area per unit length is determined, and the width change per unit length is used as the detection result.

2. The prepreg molding method according to claim 1, characterized in that, The intermediate prepreg production includes: Provides first reinforcing fiber and second reinforcing fiber; The threading plate is divided into a first hole area, a second hole area, and a third hole area, and the first hole area, the third hole area, and the second hole area are arranged along the width direction; The first reinforcing fiber is threaded through the first hole area to form the edge area, the second reinforcing fiber is threaded through the second hole area to form the main body area, and no threading is performed on the third hole area; The width of the detection area is the distance between the first reinforcing fiber and the second reinforcing fiber that are respectively connected to the detection area.

3. The prepreg molding method according to claim 1, characterized in that, Along the length direction, each of the detection intervals is connected end to end in sequence.

4. The prepreg molding method according to claim 1, characterized in that, The preset lengths of all the detection intervals are equal; and / or, The preset length is 0.8-1.5m.

5. The prepreg molding method according to claim 1, characterized in that, The process of cutting off the edge area and the detection area from the intermediate prepreg to obtain a prepreg product includes: Based on the target width of the prepreg product, the intermediate prepreg is divided into a cutting area and a product area, wherein the cutting area includes at least the edge area and the detection area; The intermediate prepreg is cut along the boundary of the cutting area, and the cut product area is used as the prepreg product.

6. A prepreg molding apparatus, characterized in that, The prepreg molding apparatus is used to implement the prepreg molding method according to claim 1. The prepreg molding apparatus is capable of online detection of the fiber straightness of the prepreg. The prepreg molding apparatus includes: The production department is used to produce intermediate prepreg, which includes an edge region, a detection region, and a main body region arranged sequentially along the width direction of the intermediate prepreg. In the width direction, the detection region fills the gap between the edge region and the main body region. Both the edge region and the main body region include a resin matrix and reinforcing fibers. The detection unit is used to detect the width change of the detection area to obtain the fiber alignment. The width of the detection area is the distance between the two reinforcing fibers that are respectively connected to the detection area in the edge area and the main body area. A cutting section is used to cut off the edge area and the detection area from the intermediate prepreg to obtain a prepreg product.

7. The prepreg molding apparatus according to claim 6, characterized in that, The detection unit includes an edge detector and a detection control center. The edge detector has the function of acquiring the edges of two reinforcing fibers that are respectively connected to the detection area in the edge area and the main body area. The detection control center is used to calculate and output the fiber collimation based on the edges.

8. The prepreg molding apparatus according to claim 6, characterized in that, The cutting section includes a cutting blade and an adjustment assembly, the adjustment assembly being used to adjust the position and orientation of the cutting blade.

Images