A method of hot press forming a preform with a spacer

Abstract

The present application relates to the technical field of composite material forming, and particularly relates to a kind of frame heat moulding preforming method, the method is according to the three-dimensional configuration of arc-shaped frame to determine the unfolding profile, and the arc-shaped flat plate including web area, inner edge strip area, outer edge strip area is obtained by laying and pasting prepreg, and outer mould pressing unit, middle mould pressing unit and inner mould pressing unit are correspondingly configured, each mould pressing unit includes oppositely arranged upper die and lower die, and a plurality of upper die and lower die are arranged along the arc length direction;Arc-shaped flat plate is placed in the feeding plane, and is pressed tightly and heated to soften from both sides;At least one of outer mould pressing unit and inner mould pressing unit is driven to move along the thickness direction, and the edge strip area is bent into forming gap to form edge strip;After cooling and setting, demoulding is carried out.The present application avoids fiber slip and wrinkle in the transition area of web and edge strip by the cooperation of partitioned pressing and differential bending, and the preforming of Z-shaped and C-shaped frame can be completed on the same set of equipment, and the present application is suitable for high-quality preforming of large-size arc-shaped frame.

Description

Technical Field

[0001] This invention relates to the field of composite material molding technology, and in particular to a hot molding preforming method for partition frames. Background Technology

[0002] Composite materials are widely used in aircraft fuselage structures due to their advantages such as high specific strength, high specific stiffness, and strong design flexibility. As the main lateral load-bearing component of the fuselage, the fuselage bulkhead is often a large-sized arc-shaped structure with a Z-shaped or C-shaped cross-section, consisting of a web and flanges located on both sides of the web. These bulkheads are generally made from prepreg, first producing a preform that matches the part's configuration, and then curing it to obtain the final part. The accuracy of the fiber orientation and the appearance quality of the preform directly determine the mechanical properties of the bulkhead.

[0003] Currently, the preforming of curved partition frames mainly relies on manual layering or simple mold pressing: operators lay and fold the prepreg layer by layer onto the tooling surface, or apply pressure to the material layers with simple pressing tooling to form the mold. For large-sized curved partition frames with an arc length of several meters, the material in the flange area needs to undergo bending deformation and interlayer slippage during the transformation of the prepreg from a planar state to a Z-shaped or C-shaped cross-section, and the stress in the transition area between the web and the flange is complex. When forming using the above methods, the deformation process of the material layers is difficult to control, and defects such as fiber slippage, fiber orientation deviation from the design direction, wrinkles, and uneven thickness are prone to occur in the transition area.

[0004] Therefore, how to provide a preforming method for large-sized curved composite material frames that has a controllable molding process and can avoid fiber slippage and wrinkling in the transition area between the web and the flange is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] This invention provides a hot molding preforming method for partition frames, which can effectively solve the problems in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for hot molding preforming of a partition frame includes the following steps: The unfolded outline is determined according to the three-dimensional configuration of the arc-shaped partition frame, and the prepreg is laid on the unfolded outline to obtain an arc-shaped flat plate. The arc-shaped flat plate includes a web area and an inner edge strip area and an outer edge strip area located on both sides of the width direction of the web area. The outer edge strip area, the web area and the inner edge strip area are respectively provided with an outer molding unit, a middle molding unit and an inner molding unit. Each molding unit includes an upper mold and a lower mold that are arranged opposite to each other on both sides of the arc-shaped plate, and multiple molds are arranged along the arc length direction of the arc-shaped plate. The arc-shaped plate is placed on the feeding plane formed by each of the lower molds, and each molding unit is driven to press it from both sides of the arc-shaped plate and heat it to soften it to the molding temperature; By driving at least one of the outer molding unit and the inner molding unit to move along the thickness direction of the arc-shaped plate, the corresponding edge strip area is bent into the molding gap between the middle molding unit and the outer molding unit and / or the inner molding unit to form an edge strip; Maintain the molding position and allow cooling. After cooling and solidification, release the constraints of each molding unit and complete demolding.

[0007] Furthermore, the unfolded contour is determined based on the structural dimensions of the web, inner edge strip, and outer edge strip of the arc-shaped partition frame, and the arc-shaped flat plate is laid using an automatic wire laying or automatic tape laying method. The fiber direction of the web region is set according to the design fiber direction of the arc-shaped partition, and the fibers of the inner edge strip region and the outer edge strip region extend continuously from the web region.

[0008] Furthermore, during the laying process of the arc-shaped flat plate, the laying thickness is greater than the actual thickness of the arc-shaped frame, and a process allowance area to be removed is set at its edge contour. The process allowance area is provided with a positioning structure that cooperates with the positioning component on the molding unit, as well as a temperature detection component.

[0009] Furthermore, a deformation release port is provided in the process allowance area located in the outer edge strip area, and multiple deformation release ports are provided along the arc length direction of the arc-shaped plate; Multiple temperature sensing elements are provided in the process allowance area, and each corresponds to at least two areas of the inner edge strip area, the web area and the outer edge strip area respectively; When each of the temperature sensors determines that the molding temperature has been reached, the inner molding unit and / or the outer molding unit are controlled to start moving.

[0010] Furthermore, during the process of driving the molding unit to press and heat the arc-shaped plate from both sides, the upper mold and the lower mold are driven to move relative to each other to a set position; When the upper mold and the lower mold move to the set position under normal conditions, the height of the gap between them is not less than the actual thickness of the arc-shaped partition and is less than the thickness of the arc-shaped plate.

[0011] Furthermore, the molding gap between the middle molding unit and the outer molding unit and / or the inner molding unit is set as the sum of the actual thickness of the arc-shaped spacer and the interlayer slip compensation amount, wherein the interlayer slip compensation amount is used to provide space for the relative slippage between each layer of prepreg when the corresponding edge strip area is bent.

[0012] Furthermore, when the cross-section of the arc-shaped partition is Z-shaped, the middle molding unit is kept stationary, and the outer molding unit and the inner molding unit are driven to move in opposite directions along the thickness direction of the arc-shaped plate, so that the outer edge strip area and the inner edge strip area bend in opposite directions; When the arc-shaped partition is C-shaped, the middle molding unit remains stationary, and the outer molding unit and the inner molding unit are driven to move in the same direction along the thickness direction of the arc-shaped plate, so that the outer edge strip area and the inner edge strip area bend in the same direction.

[0013] Furthermore, both the upper mold and the lower mold include a heating plate and a forming mold disposed thereon, the forming mold being adapted to the curvature of the arc-shaped plate; For arc-shaped partitions with different curvatures, replace the forming mold with the corresponding curvature, and set the number of forming molds arranged along the arc length direction of the arc-shaped plate.

[0014] Furthermore, the molding die is fixed to the heating plate by negative pressure adsorption. When the molding die is replaced, the negative pressure adsorption between the heating plate and the molding die is released.

[0015] A hot-molding preforming system for an arc-shaped composite material partition frame, comprising: A hot molding equipment, comprising an outer molding unit, a middle molding unit, and an inner molding unit respectively corresponding to the outer edge strip area, the web area, and the inner edge strip area of ​​the arc-shaped plate. Each molding unit includes an upper mold and a lower mold located on both sides of the thickness direction of the arc-shaped plate and arranged opposite to each other, as well as a driving component for driving the upper mold and the lower mold to move along the thickness direction of the arc-shaped plate. A control device, connected to each of the driving components, is used to control the hot molding equipment to perform the hot molding preforming method of the partition frame.

[0016] The technical solution of this invention can achieve the following technical effects: This invention decomposes the preforming of an arc-shaped partition into controlled processes: arc-shaped flat plate laying, zoned pressing and heating, differential bending of the flange strips, and cooling, shaping, and demolding. Through intermediate molding units, inner molding units, and outer molding units strategically positioned corresponding to the web area, inner flange strip area, and outer flange strip area, the arc-shaped flat plate is pressed and softened to the molding temperature on both sides. Then, the outer molding unit and / or inner molding unit move along the thickness direction to bend the flange strip area into the molding gap. Under pressure, the fibers in the web area are locked, and the flange strip area is bent in a controlled manner with fully softened resin and optimal interlayer slippage. The molding gap provides space for relative slippage between layers, thus avoiding fiber slippage and wrinkling problems in the transition area between the web and flange strip. The fiber orientation of the preform is consistent with the design direction, and the molding quality no longer depends on the operator's experience. This solves the problem that existing manual layup or simple mold pressing methods cannot consistently obtain high-quality, large-size arc-shaped partition preforms. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of an arc-shaped flat plate; Figure 2 This is a schematic diagram of the molding unit. Figure 3 This is a schematic diagram of the cross-sectional arrangement of the molding unit; Figure 4 A schematic diagram of the Z-shaped arc-shaped partition frame forming process; Figure 5 A schematic diagram of the C-shaped arc-shaped partition frame forming process; Reference numerals: 1. Arc-shaped flat plate; 11. Web area; 12. Inner edge strip area; 13. Outer edge strip area; 14. Deformation release port; 15. Positioning structure; 21. Outer molding unit; 22. Middle molding unit; 23. Inner molding unit; 31. Upper mold; 32. Lower mold. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] This invention relates to the field of composite material molding technology, particularly suitable for the preforming of curved bulkheads in aircraft composite fuselages. In this scenario, the curved bulkheads are often large-sized curved structures with Z-shaped or C-shaped cross-sections, requiring high accuracy in fiber orientation and high preforming quality. In practical applications, the preforming of such bulkheads often relies on manual lay-up or simple mold pressing. For long curved parts, manual operation suffers from poor consistency, easily leading to fiber deflection, wrinkles, and uneven thickness. During preforming, fiber slippage can easily occur in the transition area between the web and the flange, causing the fiber orientation to deviate from design requirements. Furthermore, it is difficult to simultaneously meet the molding requirements of both Z-shaped and C-shaped cross-sections within the same set of process equipment. To address these problems, this invention provides a hot-molding preforming method for bulkheads.

[0022] Example 1: In this embodiment, the hot molding preforming method for the partition frame includes the following steps: S1: Determine the unfolded outline based on the three-dimensional configuration of the arc-shaped partition frame, and lay the prepreg based on the unfolded outline to obtain the arc-shaped plate 1. The arc-shaped plate 1 includes a web area 11 and an inner edge strip area 12 and an outer edge strip area 13 located on both sides of the width direction of the web area 11. S2: The outer edge strip area 13, the web area 11 and the inner edge strip area 12 are respectively provided with an outer molding unit 21, a middle molding unit 22 and an inner molding unit 23. Each molding unit includes an upper mold 31 and a lower mold 32 that are arranged opposite to each other on both sides of the arc-shaped plate 1, and multiple molds are arranged along the arc length direction of the arc-shaped plate 1. S3: Place the arc-shaped plate 1 on the feeding plane formed by each lower mold 32, drive each molding unit to press it from both sides of the arc-shaped plate 1, and heat and soften it to the molding temperature; S4: By driving at least one of the outer molding unit 21 and the inner molding unit 23 to move along the thickness direction of the arc-shaped plate 1, the corresponding edge strip area is bent into the forming gap between the middle molding unit 22 and the outer molding unit 21 and / or the inner molding unit 23 to form an edge strip; S5: Maintain the molding position and cool. After cooling and solidification, release the constraints of each molding unit and complete demolding.

[0023] In this embodiment, the arc-shaped partition frame is pre-formed by flat plate laying, partitioned pressing, overall heating, and differential molding. The bending of the flange strip is controlled under the condition that the resin is fully softened. The fiber slippage and wrinkling problems in the transition area between the web and the flange strip are improved. At the same time, the large-size arc-shaped partition frame can be pre-formed in one clamping, which changes the situation that the existing manual lay-up has poor consistency and the simple mold pressing is difficult to adapt to large-size arc-shaped parts.

[0024] like Figure 1 As shown, for step S1, as a further implementation, the unfolding outline is determined according to the structural dimensions of the web, inner edge strip and outer edge strip of the arc-shaped partition frame, and the arc-shaped flat plate 1 is laid by automatic fiber laying or automatic tape laying; the fiber direction of the web area 11 is set according to the designed fiber direction of the arc-shaped partition frame, and the fibers of the inner edge strip area 12 and the outer edge strip area 13 extend continuously from the web area 11.

[0025] During implementation, the two laying methods can be selected based on the width of the spacer frame and the complexity of the layup. When there are many layups and complex contour changes, the automatic fiber placement method is preferred to ensure the laying accuracy at the boundary of the unfolded contour. In this embodiment, a carbon fiber / epoxy prepreg system is used, and the arc length of the arc-shaped plate 1 formed by laying is 5 meters. According to the stress requirements of the spacer frame, layups can be added in the corresponding areas of the arc-shaped plate 1 to form local reinforcement areas. Since the fibers in the flange area extend continuously from the web area 11, there is no fiber breakage or overlap interface between the web and the flange after bending and forming. The fiber continuity of the spacer frame in the transition area is guaranteed, which is difficult to achieve stably by manual sectional laying method.

[0026] During the laying process of the arc-shaped flat plate 1, the laying thickness is greater than the actual thickness of the arc-shaped partition, and a process allowance area to be cut off is set at its edge contour; a positioning structure 15 that cooperates with the positioning part on the molding unit and a temperature detection part are set in the process allowance area.

[0027] The reason for reserving the paving thickness is that there is looseness between the layers of prepreg. During the compaction and heating process, the material layer is gradually compacted. The paving thickness is determined according to the principle of reaching the actual thickness after compaction. The actual thickness can be verified by the data obtained from multi-point measurement of the curved plate 1 after paving is completed.

[0028] The positioning structure 15 can be implemented in ways including but not limited to positioning openings at both ends of the arc-shaped plate 1 along its length, with the corresponding positioning pins set on the lower mold 32.

[0029] Thermocouples or infrared temperature sensors can be used for temperature detection. Thermocouples pre-embedded in the process allowance area are preferred, as the temperature measured by them is the temperature of the material layer itself, which can more accurately reflect the softening state of the prepreg than the temperature of the mold.

[0030] The positioning structure 15 and the temperature detection component are both located in the process allowance area. After preforming, they are cut off along with the process allowance area, leaving no process marks on the frame body.

[0031] As a further optimization of the above method, a deformation release port 14 is provided in the process allowance area located at the outer edge strip area 13, and multiple deformation release ports 14 are provided along the arc length direction of the arc-shaped plate 1; multiple temperature detection elements are provided in the process allowance area, and each corresponds to at least two areas of the inner edge strip area 12, the web area 11 and the outer edge strip area 13; when each temperature detection element determines that the molding temperature has been reached, the inner molding unit 23 and / or the outer molding unit 21 are controlled to start moving.

[0032] The outer edge strip area 13 is located on the outside of the arc contour. When bending, the fibers in this area need to undergo large in-plane shear deformation. The deformation release port 14 provides a space for fiber shearing and sliding, avoiding the material from squeezing each other and wrinkling during the outer edge strip folding process. The position of the deformation release port 14 can be set to correspond to the opening position of the outer edge of the partition frame part, and also serve as the pre-set contour of the part opening, realizing the integration of process function and structural function.

[0033] Considering the large size of the curved plate 1, the temperature detection components are arranged in multiple areas. The temperature rise of each area may be asynchronous. The condition for starting the bending action of the flange strip is that each area reaches the forming temperature. This can avoid the material layer that is not fully softened in some areas being pulled or the fibers being deflected during bending.

[0034] like Figure 2 and Figure 3 As shown, for steps S2 and S3, multiple molding units are set along the arc length direction. In the specific implementation process, a total of 5 sets of molding units are arranged along the arc length direction. The effective length of each set along the arc length direction is 1 meter. They are spliced ​​together to form an effective molding length of 5 meters that matches the arc plate 1. By splicing multiple molds to adapt to the overall arc part, the problem of difficult processing and debugging of the integral mold under large size is avoided. Before placing the arc plate 1, the material feeding plane of each lower mold 32 is adjusted to be coplanar. After the surface of the arc plate 1 is covered with a release film, it is transferred to the material feeding plane. The release film separates the prepreg from the mold surface, which is convenient for demolding after cooling and shaping.

[0035] During the process of driving the molding unit to press and heat the arc-shaped plate 1 from both sides, the upper mold 31 and the lower mold 32 are driven to move relative to each other to a set position. When the upper mold 31 and the lower mold 32 move to the set position under normal conditions, the gap height between them is not less than the actual thickness of the arc-shaped partition and is less than the thickness of the arc-shaped plate 1.

[0036] This gap setting allows the material layer to withstand continuous compaction under compressed conditions, locking the fibers in the web region 11 and providing a constraint basis to prevent fiber slippage in the web region 11 during subsequent flange bending. The difference between the gap height and the thickness of the curved plate 1 ranges from 0.05 to 0.2 mm, with 0.05 mm, 0.1 mm, and 0.2 mm being suitable for practical applications. The lower limit of the difference is set at 0.05 mm because insufficient compaction force occurs when the difference is less than 0.05 mm, and the tension generated by flange bending will cause the web region 11 to move. The upper limit of the difference is set at 0.2 mm because excessive compression occurs when the difference is greater than 0.2 mm, resulting in excessive resin extrusion at low viscosity, leading to a resin-poor preform with a thickness lower than the design value.

[0037] Regarding heating, the molding temperature is determined based on the viscosity-temperature characteristics of the prepreg resin system. The temperature corresponding to the lowest point of resin viscosity is taken. In this embodiment, the epoxy resin system corresponds to 75°C. After all temperature detection components reach the molding temperature, the mold position is kept unchanged and the temperature is maintained for 5 to 10 minutes to allow the resin to soften fully and the interlayer slippage ability to reach the optimal state.

[0038] For step S4, the molding gap between the middle molding unit 22 and the outer molding unit 21 and / or the inner molding unit 23 is set as the sum of the actual thickness of the arc-shaped partition and the interlayer slip compensation amount. The interlayer slip compensation amount is used to provide space for the relative slippage between each layer of prepreg when the corresponding edge strip area is bent.

[0039] The interlayer slip compensation value ranges from 0.1 to 0.5 mm. In practical applications, three specifications of 0.1 mm, 0.3 mm, and 0.5 mm can be selected. The specific value depends on the compression characteristics of the prepreg and the layup thickness. The lower limit of the compensation is set at 0.1 mm because when the compensation is less than 0.1 mm, the forming gap constrains the material layer too tightly. When bending, the inner and outer layups cannot produce the relative slip required for bending deformation, and the fibers at the root of the edge strip will stack and wrinkle. The upper limit of the compensation is set at 0.5 mm because when the compensation is greater than 0.5 mm, the material layer in the edge strip area loses effective mold constraint during bending, which will also induce wrinkles, and the edge strip thickness control accuracy will decrease.

[0040] like Figure 4 As shown, this embodiment uses a Z-shaped cross-section arc frame as an example to illustrate the execution process of step S4: When the cross-section of the arc frame is Z-shaped, the middle molding unit 22 is kept stationary, and the outer molding unit 21 and the inner molding unit 23 are driven to move in opposite directions along the thickness direction of the arc plate 1, so that the outer edge strip area 13 and the inner edge strip area 12 bend in opposite directions.

[0041] During the bending process, the moving speed of the outer molding unit 21 and the inner molding unit 23 ranges from 1 to 5 mm / min. In practical applications, three specifications can be selected: 1 mm / min, 3 mm / min, and 5 mm / min, with 3 mm / min being the preferred choice. The lower limit of the speed is set at 1 mm / min because when the speed is lower than 1 mm / min, the preforming cycle of a single part is too long, and the resin remains in a low-viscosity heat preservation state for a long time, which is not conducive to production cycle control. The upper limit of the speed is set at 5 mm / min because when the speed is higher than 5 mm / min, the layers cannot complete the relative sliding in time, and local stress concentration and wrinkles occur at the bending point of the flange. The flanges on both sides bend synchronously in opposite directions, and the bending forces are balanced in the web area 11. With the clamping constraint of the web area 11, the arc-shaped flat plate 1 does not move as a whole during the molding process.

[0042] For step S5, after the edge strip is bent into place, each molding unit maintains the molding position and cools the material layer. When the temperature detected by the temperature detection component drops to 30°C or below, the resin viscosity recovers and the shape of the preform stabilizes. At this time, the constraints of each molding unit are released and demolding is completed. The preform is taken out and the process allowance area is cut off.

[0043] Example 2: This embodiment is for an arc-shaped partition with a C-shaped cross section. The only difference from Embodiment 1 is the bending action of the edge strip in step S4. All other steps and parameter settings are the same as in Embodiment 1.

[0044] like Figure 5 As shown, when the arc-shaped partition is C-shaped, the middle molding unit 22 is kept stationary, and the outer molding unit 21 and the inner molding unit 23 are driven to move in the same direction along the thickness direction of the arc-shaped plate 1, so that the outer edge strip area 13 and the inner edge strip area 12 bend in the same direction.

[0045] The same molding unit can switch between Z-shaped and C-shaped cross-sectional configurations simply by changing the movement direction of the outer molding unit 21 and the inner molding unit 23, without changing the process equipment. This improves the problem in the existing preforming process that a mold can only correspond to a single cross-sectional configuration and the equipment has poor versatility.

[0046] Example 3: This embodiment further explains the structure of the upper mold 31 and the lower mold 32 in the molding unit.

[0047] like Figure 2 As shown, both the upper mold 31 and the lower mold 32 include a heating plate and a forming mold disposed thereon. The forming mold is adapted to the curvature of the arc plate 1. For arc frames with different curvatures, the forming mold with the corresponding curvature is replaced, and the number of forming molds arranged along the arc length direction of the arc plate 1 is set accordingly.

[0048] The heating plate has a heat exchange channel inside, which is connected to the water temperature controller through pipeline. During the heating stage, hot water is circulated from the water temperature controller to the heating plate, and the heat is conducted to the material layer through the forming mold. During the cooling stage, cold water is circulated to remove the heat. Heating and cooling share the same heat exchange structure. The material layer temperature rises and falls evenly, and the temperature control accuracy is achieved by the water temperature controller.

[0049] The mold is divided into two parts: a heating plate and a forming mold. The heating plate and its drive and piping are general-purpose parts. The curvature-related surfaces are concentrated in the forming mold. For partition products with different curvature radii and different arc lengths, the production line can be switched by simply changing the forming mold and increasing or decreasing its number. The equipment investment cost is amortized as the product model increases.

[0050] As a further optimization of the above structure, the molding die is fixed to the heating plate by negative pressure adsorption. When replacing the molding die, the negative pressure adsorption between the heating plate and the molding die is released. The molding die and the heating plate can be detachably fixed by bolt connection in addition to negative pressure adsorption. Other connection methods that can reliably fix the two and facilitate disassembly are also applicable.

[0051] Example 4: This embodiment provides a hot molding preforming system for an arc-shaped composite material partition frame, used to perform the hot molding preforming method for partition frames described in any one of Embodiments 1 to 3.

[0052] The system includes a hot molding equipment, which includes an outer molding unit, a middle molding unit, and an inner molding unit that are respectively arranged corresponding to the outer edge strip area, the web area, and the inner edge strip area of ​​the arc-shaped plate. Each molding unit includes an upper mold and a lower mold located on both sides of the thickness direction of the arc-shaped plate and arranged opposite to each other, as well as a driving component that drives the upper mold and the lower mold to move along the thickness direction of the arc-shaped plate. The control device, connected to each drive component, is used to control the hot molding equipment to perform the frame hot molding preforming method.

[0053] By combining the above systems and methods, the problems of poor consistency in manual operation, easy slippage and wrinkling in the transition area between the web and the flange, and difficulty in sharing process equipment for Z-shaped and C-shaped configurations in the existing large-size arc-shaped composite frame preforming have been solved.

[0054] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of the application as defined herein, and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A method for hot molding preforming of a partition frame, characterized in that, Includes the following steps: The unfolded outline is determined according to the three-dimensional configuration of the arc-shaped partition frame, and the prepreg is laid on the unfolded outline to obtain an arc-shaped flat plate. The arc-shaped flat plate includes a web area and an inner edge strip area and an outer edge strip area located on both sides of the width direction of the web area. The outer edge strip area, the web area and the inner edge strip area are respectively provided with an outer molding unit, a middle molding unit and an inner molding unit. Each molding unit includes an upper mold and a lower mold that are arranged opposite to each other on both sides of the arc-shaped plate, and multiple molds are arranged along the arc length direction of the arc-shaped plate. The arc-shaped plate is placed on the feeding plane formed by each of the lower molds, and each molding unit is driven to press it from both sides of the arc-shaped plate and heat it to soften it to the molding temperature; By driving at least one of the outer molding unit and the inner molding unit to move along the thickness direction of the arc-shaped plate, the corresponding edge strip area is bent into the molding gap between the middle molding unit and the outer molding unit and / or the inner molding unit to form an edge strip; Maintain the molding position and allow cooling. After cooling and solidification, release the constraints of each molding unit and complete demolding.

2. The method for hot molding preforming of a partition frame according to claim 1, characterized in that, The unfolded contour is determined based on the structural dimensions of the web, inner edge strip, and outer edge strip of the arc-shaped partition, and the arc-shaped flat plate is laid using an automatic wire laying or automatic tape laying method. The fiber direction of the web region is set according to the design fiber direction of the arc-shaped partition, and the fibers of the inner edge strip region and the outer edge strip region extend continuously from the web region.

3. The method for hot molding preforming of a partition frame according to claim 1, characterized in that, During the laying process of the arc-shaped flat plate, the laying thickness is greater than the actual thickness of the arc-shaped partition, and a process allowance area to be removed is set at its edge contour. The process allowance area is provided with a positioning structure that cooperates with the positioning component on the molding unit, as well as a temperature detection component.

4. The method for hot molding preforming of a partition frame according to claim 3, characterized in that, A deformation release port is provided on the process allowance area located in the outer edge strip area, and multiple deformation release ports are provided along the arc length direction of the arc-shaped plate; Multiple temperature sensing elements are provided in the process allowance area, and each corresponds to at least two areas of the inner edge strip area, the web area and the outer edge strip area respectively; When each of the temperature sensors determines that the molding temperature has been reached, the inner molding unit and / or the outer molding unit are controlled to start moving.

5. The method for hot molding preforming of a partition frame according to claim 3, characterized in that, During the process of driving the molding unit to press and heat the arc-shaped plate from both sides, the upper mold and the lower mold are driven to move relative to each other to a set position; When the upper mold and the lower mold move to the set position under normal conditions, the height of the gap between them is not less than the actual thickness of the arc-shaped partition and is less than the thickness of the arc-shaped plate.

6. The method for hot molding preforming of a partition frame according to claim 1, characterized in that, The molding gap between the middle molding unit and the outer molding unit and / or the inner molding unit is set as the sum of the actual thickness of the arc-shaped partition and the interlayer slip compensation amount. The interlayer slip compensation amount is used to provide space for the relative slippage between each layer of prepreg when the corresponding edge strip area is bent.

7. The method for hot molding preforming of a partition frame according to claim 1, characterized in that, When the cross-section of the arc-shaped partition is Z-shaped, keep the middle molding unit stationary, and drive the outer molding unit and the inner molding unit to move in opposite directions along the thickness direction of the arc-shaped plate, so that the outer edge strip area and the inner edge strip area bend in opposite directions; When the arc-shaped partition is C-shaped, the middle molding unit remains stationary, and the outer molding unit and the inner molding unit are driven to move in the same direction along the thickness direction of the arc-shaped plate, so that the outer edge strip area and the inner edge strip area bend in the same direction.

8. The method for hot molding preforming of a partition frame according to claim 1, characterized in that, Both the upper mold and the lower mold include a heating plate and a forming mold disposed thereon, the forming mold being adapted to the curvature of the arc-shaped flat plate; For arc-shaped partitions with different curvatures, replace the forming mold with the corresponding curvature, and set the number of forming molds arranged along the arc length direction of the arc-shaped plate.

9. The method for hot molding preforming of a partition frame according to claim 8, characterized in that, The molding die is fixed to the heating plate by negative pressure adsorption. When the molding die is replaced, the negative pressure adsorption between the heating plate and the molding die is released.

10. A frame hot molding preforming system, characterized in that, include: A hot molding equipment, comprising an outer molding unit, a middle molding unit, and an inner molding unit respectively corresponding to the outer edge strip area, the web area, and the inner edge strip area of ​​the arc-shaped plate. Each molding unit includes an upper mold and a lower mold located on both sides of the thickness direction of the arc-shaped plate and arranged opposite to each other, as well as a driving component for driving the upper mold and the lower mold to move along the thickness direction of the arc-shaped plate. A control device, connected to each of the driving components, is used to control the hot molding equipment to perform the hot molding preforming method of the partition frame as described in any one of claims 1 to 9.

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