Forming die and production process of arc-shaped composite material cover

Abstract

The application discloses a forming die of an arc-shaped composite material cover and a production process thereof, and the forming die comprises a bottom plate, a positioning plate and a top plate, the bottom plate is provided with a first recessed clamping position close to an edge position and a first forming surface close to a center position; the bottom surface of the positioning plate is provided with a protruding clamping position which is adaptively connected with the first recessed clamping position; the positioning plate is provided with a forming cavity surrounding the first forming surface, and the inner surface of the forming cavity is a second forming surface; the top plate is fixed on the top surface of the positioning plate, and the bottom surface of the top plate is provided with a third forming surface; the first forming surface, the second forming surface and the third forming surface jointly form a forming cavity capable of being coated with a forming material. Since the male and female films are adopted, the appearance quality of the inner and outer surfaces is good, and the inner and outer surfaces do not need to be machined; the surface carbon fibers will not be damaged due to machining, excellent mechanical properties are beneficial to be ensured, the manufacturing period is shortened, and the manufacturing cost is reduced.

Description

Technical Field

[0001] This application relates to a molding die for an arc-shaped composite material cap and its manufacturing process, belonging to the field of aerospace equipment technology. Background Technology

[0002] Composite material caps (such as) Figure 1 (As shown) Composite materials are used in a variety of industries and applications, including aerospace, automotive, medical devices, and construction. Composite materials are typically composed of two or more materials with different properties to achieve better performance than a single material, such as a higher strength-to-weight ratio, corrosion resistance, and design flexibility.

[0003] Existing composite caps generally have the following disadvantages:

[0004] 1. The original design was a single-sided mold, with one side being the vacuum bag forming surface, resulting in poor appearance quality. The outer surface and outer contour needed to be machined.

[0005] 2. Machining can damage carbon fibers and reduce their mechanical properties;

[0006] 3. It needs to be cured and molded in an autoclave, which results in higher costs.

[0007] Therefore, there is a need for a technology that can produce composite preforms using prepreg as the material, including the molds used and the specific production process. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this application provides a molding die for an arc-shaped composite material cap, comprising:

[0009] The base plate has a first recessed locking position near its edge and a first forming surface near its center.

[0010] The positioning plate has a protruding locking position on its bottom surface near the edge, which is adapted to and connected to a first recessed locking position. The top surface of the positioning plate protrudes from the top surface of the base plate. The positioning plate has a forming cavity surrounding a first forming surface near its center, and the inner surface of the forming cavity is a second forming surface.

[0011] And a top plate, the top plate being fixed to the top surface of the positioning plate, and the bottom surface of the top plate having a third forming surface near the center;

[0012] The first molding surface, the second molding surface, and the third molding surface together form a molding cavity that can be covered with molding material.

[0013] In the above technical solution, a second recessed slot is provided on the bottom surface of the top plate near the edge, and the portion of the positioning plate protruding from the top surface of the bottom plate is accommodated and fixed in the second recessed slot.

[0014] In the above technical solution, further, the main feature section of the forming cavity is arc-shaped.

[0015] In the above technical solution, further, the top plate is provided with a demolding hole, and the bottom end of a demolding bolt matched with the demolding hole acts on the top surface of the positioning plate; the top plate, the positioning plate and the bottom plate are fixedly connected by a plurality of tensioning bolts.

[0016] In the above technical solution, further, the bottom surface of the bottom plate is provided with a recessed area near the center position.

[0017] In addition, the application also provides a production process of the arc-shaped composite material cover, which uses the above forming die of the arc-shaped composite material cover, and specifically includes the following steps:

[0018] Step S1, fix the positioning plate on the top surface of the bottom plate, so that the convex clamping position is adaptively connected with the first recessed clamping position;

[0019] Step S2, lay carbon fiber prepreg or carbon fiber fabric in the area surrounded by the first forming surface and the second forming surface;

[0020] Step S3, fix the top plate on the top surface of the positioning plate, and tightly fix the top plate, the positioning plate and the bottom plate;

[0021] Step S4, place the assembled die in an oven, keep at a preset temperature for a period of time, and complete the curing and forming;

[0022] Step S5, take out the oven and cool to room temperature, and demold.

[0023] In the above technical solution, further, after step S5, it further includes:

[0024] Step S6, transfer the demolded product to a machining sequence to machine the connecting hole.

[0025] In the above technical solution, further, the top plate and the bottom plate are first tightly fixed by the tensioning bolt, the entire forming die is placed into an oven and heated to a preset temperature, and kept for a preset time; the forming die is taken out, the top plate and the bottom plate are secondly tightly fixed by the tensioning bolt, the entire forming die is again placed into the oven and heated to the preset temperature, and kept for the preset time.

[0026] In the above technical solution, further, in step S5, a demolding bolt matched with the demolding hole is used to reversely top the top plate; then the positioning plate is taken out, and the product is demolded.

[0027] In the above technical solution, further, in step S4, the temperature of the oven is 130-180℃, and the curing time in the oven is 5-8 hours.

[0028] The forming die of the arc-shaped composite material cover provided by the application has good appearance quality of the inner and outer surfaces due to the use of the male and female films, and does not need to be machined for the inner and outer surfaces. On the one hand, the production process is simplified, the production efficiency is improved, the machining equipment does not need to be used again, and the production cost is also reduced. On the other hand, the surface carbon fibers will not be damaged due to machining, which is beneficial to guarantee excellent mechanical properties. Moreover, the bolt tensioning and pressurizing, oven warming and curing forming can be used, and the comprehensive cost is lower than that of the bag press forming of the hot press tank. BRIEF DESCRIPTION OF DRAWINGS

[0029] Other features, objects and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments with reference to the attached drawings.

[0030] Figure 1 FIG. 1 is a structural schematic diagram of an arc-shaped composite material cover;

[0031] Figure 2 FIG. 6 is a perspective structural schematic diagram of a forming die of an arc-shaped composite material cover provided by an embodiment of the application;

[0032] Figure 3 FIG. 7 is an exploded view of a forming die of an arc-shaped composite material cover provided by an embodiment of the application;

[0033] Figure 4 FIG. 8 is a sectional view of a forming die of an arc-shaped composite material cover provided by an embodiment of the application;

[0034] Figure 5 FIG. 9 is a perspective structural schematic diagram of a bottom plate provided by an embodiment of the application;

[0035] Figure 6 FIG. 10 is a perspective structural schematic diagram of a positioning plate provided by an embodiment of the application;

[0036] Figure 7 FIG. 11 is a perspective structural schematic diagram of a top plate provided by an embodiment of the application;

[0037] Figure 8 FIG. 12 is a process flow diagram of a production process of an arc-shaped composite material cover provided by an embodiment of the application. BRIEF DESCRIPTION OF DRAWINGS

[0039] 100-bottom plate; 200-positioning plate; 300-top plate; 400-tensioning bolt; 500-transporting handle; 600-demolding bolt; 110-peripheral edge portion; 120-middle recessed area; 130-center protruding portion; 140-weight-reducing cavity; 131-first forming surface; 210-forming cavity; 220-protruding clamping; 211-second forming surface; 310-top plate protruding portion; 311-third forming surface. DETAILED DESCRIPTION

[0040] The technical means, creative features, purposes and effects of the present application will be further illustrated in the following detailed description.

[0041] Embodiments based on the concept of the present disclosure can be subject to various modifications and can take various forms, and thus specific embodiments will be exemplarily shown in the drawings and described in detail in the specification or application. However, this is not intended to limit embodiments based on the concept of the present disclosure to specific disclosed forms, and it is understood to include all modifications, equivalents, and alternatives within the scope of the idea and technical scope of the present disclosure.

[0042] First and / or second terms can be used to describe various constituent elements, but the constituent elements are not limited by the terms. The terms are used only for the purpose of distinguishing one constituent element from another, for example, within the limits not exceeding the scope of the right of the concept based on the present disclosure, a first constituent element can be named as a second constituent element, and similarly, a second constituent element can be named as a first constituent element.

[0043] When referring to a certain constituent element "connected" or "coupled" to another constituent element, it is understood that it can be directly connected or coupled to the other constituent element or there can be other constituent elements therebetween. In contrast, when referring to a certain constituent element "directly connected" or "directly coupled" to another constituent element, it is understood that there are no other constituent elements therebetween. Other expressions used to describe the relationship between constituent elements, i.e., "between" or "directly between" or "adjacent to" or "directly adjacent to" and the like should be interpreted similarly.

[0044] The terms used in the specification are used only to describe specific embodiments, and are not intended to limit the intent of the present disclosure. As long as there is no explicit opposite meaning in the context, the singular expression includes the plural expression. In the specification, the terms "include" or "have" or the like are intended to designate the presence of a predetermined feature, number, step, action, constituent element, component or a combination thereof, and it is understood that the existence or addition of one or more other features, numbers, steps, actions, constituent elements, components or combinations thereof is not precluded.

[0045] As long as not differently defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. Terms defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with the meaning in the context of the relevant art, and should not be ideally or excessively interpreted as a formal meaning unless explicitly defined in the specification.

[0046] Figure 1 It is a schematic view of an arc-shaped composite hatch cover structure.

[0047] As shown in Figure 1 , the main feature section of the arc-shaped composite hatch cover is arc-shaped. Due to the shape limitation, the arc-shaped composite hatch cover in the prior art generally adopts contrast heat tank bag compression molding. It is a single-sided mold, one side is a vacuum bag forming surface, and the appearance quality is poor. The outer surface and the outer contour need to be machined.

[0048] To this end, the molding mold of the arc-shaped composite hatch cover provided by the present application comprises a bottom plate, a positioning plate and a top plate. The first recessed clamping position is arranged near the edge position of the bottom plate, and the first forming surface is arranged near the center position of the bottom plate. The bottom surface of the positioning plate is provided with a protruding clamping position near the edge position, and the protruding clamping position is adaptively connected with the first recessed clamping position. The top surface of the positioning plate protrudes from the top surface of the bottom plate. The positioning plate is provided with a forming cavity around the first forming surface near the center position, and the inner surface of the forming cavity is a second forming surface. The top plate is fixed on the top surface of the positioning plate, and the third forming surface is arranged near the center position of the bottom surface of the top plate. The first forming surface, the second forming surface and the third forming surface jointly form a forming cavity capable of laying carbon fiber prepreg or carbon fiber fabric.

[0049] The molding mold of the arc-shaped composite hatch cover provided by the present application adopts yin and yang films, and the appearance quality of the inner and outer surfaces is good, without the need for machining the inner and outer surfaces. On the one hand, the production process is simplified, the production efficiency is improved, without the need for using machining equipment, and the production cost is also reduced. On the other hand, the surface carbon fiber will not be damaged due to machining, which is beneficial to guarantee excellent mechanical properties. Moreover, bolt tensioning and pressurization, oven warming and solidification molding can be adopted, and the comprehensive cost of contrast heat tank bag compression molding is relatively low.

[0050] Figure 2 It is a schematic view of the three-dimensional structure of the molding mold of the arc-shaped composite hatch cover provided by the embodiment of the present application. Figure 3 It is an exploded view of the molding mold of the arc-shaped composite hatch cover provided by the embodiment of the present application. Figure 4 It is an exploded view of the molding mold of the arc-shaped composite hatch cover provided by the embodiment of the present application.

[0051] Please refer to Figure 2 , Figure 3 and Figure 4 , the molding mold of the arc-shaped composite hatch cover provided by the embodiment of the present application comprises a bottom plate 100, a positioning plate 200, a top plate 300, a plurality of tensioning bolts 400 and at least two transfer handles 500.

[0052] The bottom plate 100 is provided with a positioning plate 200 fixing position; the positioning plate 200 is annular as a whole, and the annular positioning plate 200 is installed on the positioning plate 200 fixing position; the top plate 300 is fixedly connected with the bottom plate 100 by means of a plurality of pull-in bolts, and the top plate 300 and the bottom plate 100 clampingly fix the positioning plate 200. The bottom plate 100 is close to a first forming surface 131 at a central position; the positioning plate 200 is close to a forming cavity 210 surrounding the first forming surface 131 at a central position, and an inner surface of the cavity is a second forming surface 211; and the bottom surface of the top plate 300 is provided with a third forming surface 311 close to a central position; the first forming surface 131, the second forming surface 211 and the third forming surface 311 jointly form a forming cavity capable of laying a forming material.

[0053] In the embodiment, the forming material is carbon fiber prepreg or carbon fiber fabric.

[0054] The two transfer handles 500 are fixed on the bottom plate 100 by means of fastening bolts and are symmetrically distributed, and the transfer handles 500 facilitate the placing and taking out of the mold from the oven or facilitate the carrying and storage of the mold.

[0055] The structure of each main component is shown in Figure 5-7 The further description is made by combining with the drawings.

[0056] Figure 5 The three-dimensional structure schematic diagram of the bottom plate provided for the embodiment of the application is shown.

[0057] As shown in Figure 5 The top surface of the bottom plate 100 is provided with three layers, which are respectively an outer peripheral edge portion 110, a middle recessed area 120 and a central protruding portion 130. In the embodiment, the height of the central protruding portion 130 is higher than that of the outer peripheral edge portion 110. The middle recessed area 120 is a first recessed clamping position for fixing the positioning plate 200; and the top surface of the central protruding portion 130 is a first forming surface 131.

[0058] The longitudinal section of the bottom plate 100 is arc-shaped, and the edge of the bottom plate 100 is in a high-low undulating shape, part of which is in a protruding state and part of which is in a recessed state.

[0059] Referring to Figure 3 and Figure 4 In some embodiments, a weight-reducing cavity 140 is arranged at the central position of the bottom of the bottom plate 100, which saves material and reduces weight, and facilitates the transfer of the mold.

[0060] Figure 6 The three-dimensional structure schematic diagram of the positioning plate provided for the embodiment of the application is shown.

[0061] As shown in Figure 6As shown, the positioning plate 200 is generally ring-shaped, that is, the positioning plate 200 has a forming cavity 210 near the center position, and the bottom surface of the positioning plate 200 has a protruding locking position 220 near the edge position.

[0062] The positioning plate 200 is installed on the top surface of the base plate 100, and the protruding locking position 220 is adapted to and connected with the first recessed locking position; the top surface of the positioning plate 200 protrudes from the top surface of the base plate 100, and the forming cavity 210 is fitted onto the central protrusion 130 of the base plate 100. The height of the central protrusion 130 is less than the depth of the forming cavity 210, and the inner surface of the forming cavity 210 is the second forming surface 211.

[0063] Figure 7 A three-dimensional structural diagram of the top plate provided for an embodiment of this application.

[0064] like Figure 7 As shown, a top plate protrusion 310 is provided on the bottom surface of the top plate 300 near the center. The top plate 300 is fixedly connected to the positioning plate 200 and the bottom plate 100 by tension bolts 400. The top plate 300 is fixed on the top surface of the positioning plate 200, and its top plate protrusion 310 is installed on the upper part of the molding cavity 210. The surface of the top plate protrusion 310 is the third molding surface 311. The first molding surface 131, the second molding surface 211, and the third molding surface 311 together form a molding cavity that can be used to lay molding materials.

[0065] The longitudinal section of the top plate 300 is arc-shaped, and the edge of the bottom plate 100 is undulating, with some parts protruding and some parts concave. The protruding parts of the top plate 300 are connected to the concave parts of the bottom plate 100, and the concave parts of the top plate 300 are connected to the protruding parts of the bottom plate 100.

[0066] In some embodiments, a second recessed locking position is provided on the bottom surface of the top plate 300 near its edge. The portion of the positioning plate 200 protruding from the top surface of the bottom plate 100 accommodates and is fixed in the second recessed locking position. The bottom surface of the positioning plate 200 is fixed by a first recessed locking position of the bottom plate 100, and the top surface of the positioning plate 200 is fixed by a second recessed locking position of the top plate 300. Of course, these are only some specific embodiments of this application, and the second recessed locking position may not be provided. Precise positioning is achieved solely by the cooperation of the protruding and recessed states of the bottom plate 100 and the top plate 300.

[0067] See Figure 4 and Figure 7 The top plate 300 is provided with a demolding hole. During demolding, the demolding bolt 600 adapted to the demolding hole acts on the bottom plate 100 or the positioning plate 200, and then pulls out of the top plate 300 in the opposite direction.

[0068] Figure 8 A process flow diagram of the manufacturing process of an arc-shaped composite material cap provided for an embodiment of this application.

[0069] As Figure 8 shown, the application also provides a production process of the arc-shaped composite material cover, which uses the forming mold described above, and the production process comprises the following steps:

[0070] Step S1, fix the positioning plate 200 on the top surface of the bottom plate 100, so that the protruding clamping site 220 is adaptively connected with the first recessed clamping site;

[0071] Step S2, lay up the forming material in the area surrounded by the first forming surface 131 and the second forming surface 211;

[0072] In this embodiment, the forming material is carbon fiber prepreg or carbon fiber fabric;

[0073] Step S3, fix the top plate 300 on the top surface of the positioning plate 200, and tightly fix the top plate 300, the positioning plate 200 and the bottom plate 100;

[0074] Step S4, place the assembled mold in an oven, keep at a preset temperature for a period of time, and complete the curing forming.

[0075] In this embodiment, the preset temperature of the oven is 130-180℃, and the curing time in the oven is 5-8 hours.

[0076] Step S5, cool to room temperature and demold after taking out of the oven.

[0077] In this embodiment, the demolding process specifically comprises: using the demolding bolt 600 adaptively connected with the demolding hole to push out the top plate 300; and then taking out the positioning plate 200 to demold the product.

[0078] In some embodiments, after step S5, the process further comprises:

[0079] Step S6, the demolded product is transferred to a machining sequence to machine the connecting hole.

[0080] For the connecting hole, the machining operation is convenient and efficient, and will not damage the surface and affect the mechanical properties. Of course, the connecting hole can also be formed at one time by setting a core mold to avoid machining.

[0081] In this embodiment, the tightening of the bottom plate 100, the positioning plate 200 and the top plate 300 is performed twice:

[0082] The first tightening is performed by using the pull-in bolt to tightly fix the top plate 300 and the bottom plate 100, the entire forming mold is placed into an oven and heated to a preset temperature, and kept for a preset time; the second tightening is performed by using the pull-in bolt to tightly fix the top plate 300 and the bottom plate 100 after taking out the forming mold, and the entire forming mold is again placed into an oven and heated to a preset temperature, and kept for a preset time.

[0083] Furthermore, it should be understood that although the description is made according to the embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and the person skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment.

Claims

1. A process for producing an arc-shaped composite material cover, characterized by, The forming die of the arc-shaped composite material cover comprises: a bottom plate, which is provided with a first recessed clamping position near the edge and a first forming surface near the center; a positioning plate, the bottom surface of which is provided with a protruding clamping position near the edge, which is adaptively connected with the first recessed clamping position, and the top surface of which protrudes the top surface of the bottom plate; the positioning plate is provided with a forming cavity surrounding the first forming surface near the center, and the inner surface of the forming cavity is a second forming surface; a top plate, which is fixed on the top surface of the positioning plate and is provided with a third forming surface near the center; the top plate is provided with a demolding hole, and the bottom end of a demolding bolt adaptively connected with the demolding hole acts on the top surface of the positioning plate; the top plate, the positioning plate and the bottom plate are fixedly connected by a plurality of tensioning bolts; the first forming surface, the second forming surface and the third forming surface jointly form a forming cavity capable of laying up a forming material; the production process of the arc-shaped composite material cover specifically comprises the following steps: step S1, fixing the positioning plate on the top surface of the bottom plate so that the protruding clamping position is adaptively connected with the first recessed clamping position; step S2, laying up a forming material in the area surrounded by the first forming surface and the second forming surface; the forming material is carbon fiber prepreg or carbon fiber fabric; step S3, fixing the top plate on the top surface of the positioning plate, and tensioning and fixing the top plate, the positioning plate and the bottom plate; step S4, placing the assembled die in an oven, keeping at a preset temperature for a period of time, and completing the curing and forming; step S5, cooling to room temperature after taking out of the oven, and demolding; firstly tensioning and fixing the top plate and the bottom plate by the tensioning bolts, placing the entire forming die into an oven and heating to a preset temperature, keeping for a preset time; taking out the forming die, secondly tensioning and fixing the top plate and the bottom plate by the tensioning bolts, and placing the entire forming die into the oven again and heating to the preset temperature, keeping for the preset time.

2. The process for producing an arc-shaped composite material cover according to claim 1, wherein after step S5, further comprising: step S6, transferring the demolded product into a machining sequence to machine a connecting hole.

3. The process for producing an arc-shaped composite material cover according to claim 1, wherein in step S5, using a demolding bolt adaptively connected with the demolding hole to reversely top the top plate; then taking out the positioning plate to demold the product.

4. The process for producing an arc-shaped composite material cover according to claim 1, wherein in step S4, the temperature of the oven is 130-180℃, and the curing time in the oven is 5-8 hours.

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