A cylindrical composite material frame with mortise and tenon structure and a forming die and forming method thereof

Abstract

The application provides a cylindrical composite material frame with a mortise and tenon structure, a forming die and a forming method thereof, and belongs to the field of deep-sea exploration equipment. The application solves the problems of large ship space occupation, reduced effective load, easy fatigue of the connecting structure and low sea replacement efficiency caused by the fact that a scientific research ship needs to be equipped with multiple sets of heavy metal laying equipment to adapt to different sizes of detection equipment. The application comprises a plurality of longitudinal ribs distributed along the circumferential direction and a plurality of ring frames arranged at equal intervals along the length direction of the longitudinal ribs. A dovetail-shaped groove is arranged at the intersection of the longitudinal rib and the ring frame. The ring frame is segmented and embedded into the groove to form an integrated mortise and tenon structure. The application mainly provides a lightweight composite material frame structure for a scientific research ship, which can adapt multiple sizes of detection equipment to the same laying equipment.

Description

Technical Field

[0001] This invention belongs to the field of deep-sea exploration equipment support structure technology, and in particular relates to a cylindrical composite material frame with mortise and tenon structure, its molding mold and molding method. Background Technology

[0002] Deep-sea exploration is a crucial means of conducting marine scientific research, resource exploration, and environmental monitoring. Current underwater scientific research activities require the deployment of various types of detection instruments, floating structures, or observation platforms. These instruments vary significantly in size, often ranging from several hundred millimeters in diameter. Furthermore, these instruments typically require specialized deployment equipment for carrying, deploying, and recovering. This necessitates that research vessels be equipped with multiple sets of specialized deployment equipment or support structures of different sizes to accommodate instruments of varying diameters. Ships also need to pre-store multiple fixed deployment devices, occupying significant deck and cabin space and substantially reducing the ship's effective payload capacity. Moreover, these deployment devices must meet the complex operating conditions of the deep sea, including withstanding immense water pressure and... To resist seawater corrosion, provide necessary buoyancy adjustment, and maintain structural integrity and internal equipment connection stability in the high-pressure and low-temperature environment of the deep sea, existing deployment equipment mostly uses metal materials. These frames have high strength, but a single deployment equipment typically weighs tens to hundreds of kilograms. The combined weight of multiple deployment equipment further occupies the ship's carrying capacity. Moreover, the components of the deployment equipment are usually connected by welding or bolts. Welded points are prone to fatigue cracks under long-term dynamic loads and alternating pressures, while bolted connections require regular maintenance to prevent loosening, thus affecting the stability of the deployment equipment. Furthermore, replacing deployment equipment during offshore operations requires manual disassembly and reassembly, which is time-consuming, labor-intensive, and subject to sea conditions, making it difficult to adapt to the needs of rapid switching between multiple tasks. Summary of the Invention

[0003] In view of this, the present invention aims to propose a cylindrical composite material frame with mortise and tenon structure, as well as its molding mold and molding method, to solve the problems of large space occupation, reduced effective load, easy fatigue of connection structure and low efficiency of replacement at sea caused by the need for scientific research vessels to be equipped with multiple sets of heavy metal deployment equipment to adapt to different sizes of detection equipment.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a cylindrical composite material frame with a mortise and tenon structure, comprising several longitudinal ribs evenly distributed along the circumference and several ring frames equally spaced along the length of the longitudinal ribs, the inner arc surfaces of the longitudinal ribs forming a cylindrical support surface, the longitudinal ribs having a sandwich structure inside, the sandwich structure being filled with lightweight foam or buoyancy material, dovetail-shaped grooves being provided at the intersection of the longitudinal ribs and the ring frames, the ring frames being segmented and embedded into the grooves to form an integral mortise and tenon structure, and both the longitudinal ribs and the ring frames being made of composite materials.

[0005] Furthermore, the longitudinal ribs and the outer surface of the ring frame may or may not be covered with a skin.

[0006] Furthermore, the lightweight foam is made of polyvinyl chloride or polyester, and the buoyancy material is made of a composite of a polymer matrix material and a lightweight, pressure-resistant filler.

[0007] Furthermore, the composite material frame has an inner diameter of 50~600mm, an outer diameter of 200~800mm, a total length of 0.5~8m, and a weight of 30~200kg.

[0008] Furthermore, the inner sides of several of the longitudinal ribs form cylindrical surfaces and are connected to the equipment, while the outer sides are connected to the installation equipment.

[0009] A molding die for a cylindrical composite material frame with a mortise and tenon structure includes baffles, a central shaft, and segmented truss blocks. Baffles are provided at both ends of the central shaft, and the two baffles are coaxially arranged with the central shaft. Multiple segmented truss blocks are evenly spaced along the circumference of the central shaft. The segmented truss blocks are detachably connected to the central shaft by bolts, and an axially extending longitudinal channel is formed between adjacent segmented truss blocks. Each segmented truss block includes multiple truss units spaced apart along the length of the central shaft. Each truss unit includes a central truss block and two side trusses, with the central truss block connected to the side trusses on both sides. An annular channel is formed between adjacent truss units, and the cross-section of the annular channel has a tapered structure that gradually narrows towards the central shaft.

[0010] Furthermore, the segmented truss assembly is connected to the central shaft by bolts.

[0011] Furthermore, the baffle, central shaft, and segmented truss assembly are all made of metal.

[0012] A method for molding a cylindrical composite material frame with a mortise and tenon structure includes the following steps: S1: The longitudinal ribs are molded using carbon fiber or glass fiber prepreg material, and dovetail grooves are machined at the connection positions between the longitudinal ribs and the ring frame. S2: Install the longitudinal ribs in the longitudinal channels of the forming mold; S3: The ring frame is formed by wet winding of carbon fiber or glass fiber. By controlling the winding tension and the change of fiber layer width, the fiber-reinforced prepreg gradually widens on both sides of the longitudinal rib intersection and fills the dovetail groove from top to bottom for curing. S4: After curing, it forms an integrated structure in which the longitudinal ribs are connected to the ring frame by tenon and mortise; S5: The segmented separation mold assembly is used to demold, resulting in a cylindrical composite material frame with mortise and tenon structure.

[0013] Furthermore, the S5 also includes the option of providing a skin or not providing a skin on the outer surface of a cylindrical composite frame with mortise and tenon joints.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention changes the inner diameter of the deployment equipment by using cylindrical composite material frames of different sizes, allowing a single deployment equipment to house composite material frames of different sizes. This enables a single deployment equipment to deploy various sizes of detection equipment or floating bodies, thus solving the problem of research vessels needing to be equipped with multiple sets of heavy metal deployment equipment that occupy ship space. The longitudinal ribs and ring frames in the composite material frame are all made of composite materials, which greatly reduces the weight of the frame while ensuring structural stability and rigidity. Furthermore, the longitudinal ribs and ring frames are precisely fitted together through a dovetail tenon and mortise structure. The inclination angle of the dovetail groove sidewall of the longitudinal rib matches the inclination angle of the ring frame sidewall to achieve self-locking, avoiding the risk of welding fatigue cracks and bolt loosening. It maintains connection integrity under deep-sea alternating pressure, requires no maintenance, and has a long service life. 2. The longitudinal rib sandwich structure of the present invention is filled with lightweight foam or deep-sea solid buoyancy material, which makes the weight of a single frame much lower than that of traditional metal structures, reducing the burden on ships. The lightweight foam or buoyancy material further provides pressure resistance and buoyancy, reducing the pressure load on the frame in the deep sea, enhancing the stability of the device, and further enhancing the corrosion resistance of the frame by setting a skin on the frame surface, thereby extending the service life of the frame. 3. The composite material frame of the present invention only needs to be manually embedded into the installation equipment, which solves the problem of time-consuming replacement of existing installation equipment; 4. The composite material frame molding mold of the present invention forms a conical mating surface by the axial cross section of the middle truss block being a tapered shape with a wider inner section and a narrower outer section, and the side truss blocks being a tapered shape with a narrower inner section and a wider outer section. After the product is cured and the central shaft is removed, the middle truss block falls inward along the conical mating surface under external force. After the middle truss block is removed, the circumferential constraint of the side truss block is released, and it can be separated by moving it outward directly. This avoids the generation of lateral shear force during demolding, which would damage the product structure. At the same time, it solves the problem of complicated demolding operation. Furthermore, the split truss block units are independently connected to the central shaft by bolts, thereby realizing independent disassembly and replacement, which is convenient for independent disassembly and replacement, shortens maintenance time, and can also change the width of the longitudinal channel by changing the distance between the segmented truss block groups, and can also change the depth of the annular channel by changing the distance between the truss block units, thereby adapting to multi-specification production. Attached Figure Description

[0015] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1This is a schematic diagram of the axial side structure of a cylindrical composite material frame with mortise and tenon joints without skin, as described in this invention. Figure 2 This is a front structural diagram of a cylindrical composite material frame with a mortise and tenon structure according to the present invention. Figure 3 This is a cross-sectional structural diagram of a cylindrical composite material frame with a mortise and tenon structure according to the present invention. Figure 4 This is a schematic diagram of the axonometric structure of a cylindrical composite material frame with a mortise and tenon structure and a skin structure according to the present invention. Figure 5 This is a schematic cross-sectional view of a cylindrical composite material frame with a mortise and tenon structure and a skin structure according to the present invention. Figure 6 This is a schematic diagram of the axial side structure of a molding die for a cylindrical composite material frame with a tenon and mortise structure according to the present invention. Figure 7 This is a front view of the molded structure of a cylindrical composite material frame with mortise and tenon joints according to the present invention. Figure 8 This is a schematic diagram of the cross-sectional structure of a molding die for a cylindrical composite material frame with a tenon and mortise structure according to the present invention, along point AA. Figure 9 This is a schematic diagram of the cross-sectional structure of the molding die for a cylindrical composite material frame with a tenon and mortise structure according to the present invention, along the BB section.

[0016] In the picture: 1. Longitudinal ribs; 2. Ring frame; 3. Sandwich structure; 4. Skin; 5. Baffle; 6. Side trusses; 7. Middle trusses; 8. Central axis; 9. Longitudinal channel; 10. Annular channel. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0018] Detailed implementation method: See Figure 1-5This embodiment describes a cylindrical composite material frame with a mortise and tenon structure, comprising several longitudinal ribs 1 evenly distributed along the circumference and several ring frames 2 equally spaced along the length of the longitudinal ribs 1. The inner arc surfaces of the longitudinal ribs 1 form a cylindrical support surface. In practical applications, there are at least three longitudinal ribs 1 and at least three ring frames 2, thus forming a composite material frame for enclosing detection equipment or a floating body. The longitudinal ribs 1 have a sandwich structure 3 inside, which is filled with lightweight foam or buoyancy material to reduce the overall weight of the frame while providing dovetail-shaped grooves at the intersection of the longitudinal ribs 1 and the ring frames 2. The ring frames 2 are segmented and embedded into the grooves to form an integrated mortise and tenon structure. The connection between the longitudinal ribs 1 and the ring frames 2 is interlocked through the grooves on the longitudinal ribs 1 and the protrusions on the ring frames 2, avoiding stress concentration at the nodes, thereby enabling quick disassembly and reassembly and supporting modular replacement. Both the longitudinal ribs 1 and the ring frames 2 are made of composite material, namely carbon fiber epoxy resin.

[0019] This invention provides a cylindrical frame, mainly comprising longitudinal ribs 1 and ring frames 2. The longitudinal ribs 1 and ring frames 2 are connected by mortise and tenon joints to achieve self-locking. The mortise and tenon design ensures no stress concentration at the nodes, improving the overall strength. By replacing structural components of different diameters, one frame can be adapted to multiple specifications of detection equipment or floats, avoiding the need to carry multiple dedicated deployment equipment. The overall weight of the composite material frame made of carbon fiber and epoxy resin is reduced by 40% compared to aluminum alloy deployment equipment.

[0020] The longitudinal ribs 1 and the ring frame 2 are covered with skin 4 or not covered with skin 4. When the frame surface is covered with skin 4, skin 4 and the frame together form a closed load-bearing shell to bear the pressure load inside and outside the frame. When the frame surface is not covered with skin 4, the frame serves as an independent support structure, which facilitates pipeline layout and equipment maintenance.

[0021] The lightweight foam is made of polyvinyl chloride or polyester, and the buoyancy material is made of a composite of a polymer matrix material and a lightweight pressure-resistant filler. The polymer matrix material is epoxy resin, and the lightweight pressure-resistant filler is hollow glass microspheres. The buoyancy material has the characteristics of lower density than water, corrosion resistance, and high compressive strength. The lightweight foam and buoyancy material provide support for the longitudinal rib 1 while providing buoyancy for the frame.

[0022] The composite material frame has an inner diameter of 50~600mm, an outer diameter of 200~800mm, a total length of 0.5~8m, and a weight of 30~200kg. It can cover the specifications of mainstream deep-sea exploration equipment. A single frame can replace multiple traditional supports, which is convenient for manual installation. The maximum size frame of 200kg is still 40% lighter than aluminum alloy.

[0023] Several longitudinal ribs 1 form cylindrical surfaces on their inner sides and are connected to the equipment. The cylindrical surfaces formed on the inner sides can accurately wrap the outer surface of the equipment to avoid shaking or displacement. The outer sides are connected to the deployment equipment. When in use, the inner diameter of the deployment equipment can be changed by selecting frames of different sizes, so that one deployment equipment can deploy multiple devices. The devices refer to shallow-water exploration equipment or buoys and other devices.

[0024] See Figure 6-9 This embodiment describes a molding die for a cylindrical composite material frame with a mortise and tenon structure, comprising baffles 5, a central shaft 8, and segmented stringer blocks. Baffles 5 are provided at both ends of the central shaft 8, and the two baffles 5 are coaxially arranged with the central shaft 8. Each baffle 5 is a flange-type disc, and is coaxially fixed to both ends of the central shaft 8 by bolts to constrain the axial boundary of the die. Multiple segmented stringer blocks are arranged at equal intervals along the circumference of the central shaft 8. The segmented stringer blocks are detachably connected to the central shaft 8 by bolts. Adjacent segmented stringer blocks... A longitudinal channel 9 extending axially is formed between the blocks, and the longitudinal channel 9 is used to place the longitudinal rib 1; the segmented truss block group includes a plurality of truss block units spaced apart along the length direction of the central axis 8, each truss block unit includes a central truss block 7 and two side truss blocks 6, the two sides of the central truss block 7 are respectively connected to the side truss blocks 6, and the split truss block units facilitate subsequent demolding; an annular channel 10 is formed between adjacent truss block units, and the cross-section of the annular channel 10 has a tapered structure that gradually narrows towards the central axis 8, and the annular channel 10 is used to form the ring frame 2.

[0025] The segmented truss assembly is connected to the central shaft 8 by bolts, thereby enabling the detachable connection between the middle truss 7 and the side truss 6 and the central shaft 8.

[0026] The baffle 5, the central shaft 8, and the segmented truss assembly are all made of metal, thus enabling them to be reused.

[0027] See Figure 1-9 This embodiment describes a method for molding a cylindrical composite material frame with a mortise and tenon structure, comprising the following steps: S1: The longitudinal rib 1 is molded using carbon fiber or glass fiber prepreg material. That is, the prepreg material is laid into the longitudinal rib forming mold and molded and cured. After curing, a dovetail-shaped groove is machined at the connection position between the longitudinal rib 1 and the ring frame 2. In this embodiment, the upper groove width of the dovetail-shaped groove is 50mm and the lower groove bottom is 55mm. The prepreg material is fiber-reinforced prepreg material, including prepreg carbon fiber cloth, prepreg glass fiber cloth or epoxy resin-based unidirectional prepreg material. S2: Install the longitudinal rib 1 in the longitudinal channel 9 of the forming mold, ensuring that the longitudinal rib 1 fits against the side wall of the longitudinal channel 9, and that the end of the longitudinal rib 1 contacts the inner side of the baffle 5. S3: The ring frame 2 is formed by wet winding of carbon fiber or glass fiber. By controlling the winding tension and the change of fiber layer width, the fiber-reinforced prepreg gradually widens on both sides at the intersection of the longitudinal ribs 1 and fills the dovetail groove from top to bottom for curing. During the winding process, because the dovetail groove is narrow at the top and wide at the bottom, the carbon fiber or glass fiber restricts the radial movement after curing. The dovetail groove is wider on both sides than in the middle, which restricts the circumferential movement after curing. S4: After curing, it forms an integral structure in which the longitudinal rib 1 and the ring frame 2 are connected by a tenon and mortise. The slope of the ring frame 2 fits the slope of the groove of the longitudinal rib 1. After curing, the shrinkage generates radial pressure, which inhibits the axial displacement of the ring frame 2. S5: The segmented separation mold assembly is used to achieve demolding. After the product is cured, the central shaft 8 is pulled out, and then the middle truss 7 is knocked from the outside to make the middle truss 7 fall inward. Then the side trusses 6 on both sides of the middle truss 7 are removed to achieve demolding and obtain a cylindrical composite material frame with mortise and tenon structure.

[0028] S5 also includes providing a skin 4 on the outer surface of a cylindrical composite material frame with a mortise and tenon structure, or not providing a skin 4, depending on the actual application requirements to form a skin 4 on the outside of the frame.

[0029] This invention designs a cylindrical composite material frame with a mortise and tenon structure to adapt to existing deployment equipment. By replacing the composite material frame with different sizes, detection equipment and floats of different outer diameters can be deployed, which greatly saves ship space, reduces load, and increases the loading capacity of detection equipment or floats. The mass of the composite material frame is 40% less than that of aluminum alloy deployment equipment of the same size, which can save high aluminum alloy processing costs. Furthermore, the composite material frame of this invention only requires placing the equipment inside the frame and then placing the frame inside the existing deployment equipment to achieve installation. The research vessel does not need to be equipped with multiple sets of heavy metal deployment equipment, and the installation is convenient. The composite material frame made of carbon fiber and epoxy resin has excellent corrosion resistance, can adapt to the complex working conditions at sea, and is also suitable for other land-based deployment equipment.

[0030] The specific embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A cylindrical composite material frame with a mortise and tenon structure, characterized in that: It includes several longitudinal ribs (1) evenly distributed along the circumference and several ring frames (2) evenly spaced along the length of the longitudinal ribs (1). The inner arc surfaces of the longitudinal ribs (1) form a cylindrical support surface. The longitudinal ribs (1) are provided with a sandwich structure (3). The sandwich structure (3) is filled with lightweight foam or buoyancy material. The intersection of the longitudinal ribs (1) and the ring frames (2) is provided with a dovetail groove. The ring frames (2) are segmented and embedded into the groove to form an integral tenon and mortise structure. Both the longitudinal ribs (1) and the ring frames (2) are made of composite materials.

2. A cylindrical composite material frame with a mortise and tenon structure according to claim 1, characterized in that: The longitudinal ribs (1) and the ring frame (2) are covered with skin (4) or not covered with skin (4).

3. A cylindrical composite material frame with a mortise and tenon structure according to claim 1, characterized in that: The lightweight foam is made of polyvinyl chloride or polyester, and the buoyancy material is made of a composite of a polymer matrix material and a lightweight pressure-resistant filler.

4. A cylindrical composite material frame with a mortise and tenon structure according to claim 1, characterized in that: The composite material frame has an inner diameter of 50~600mm, an outer diameter of 200~800mm, a total length of 0.5~8m, and a weight of 30~200kg.

5. A cylindrical composite material frame with a mortise and tenon structure according to claim 1, characterized in that: Several longitudinal ribs (1) form a cylindrical surface on their inner side and are connected to the equipment, while their outer side is connected to the installation equipment.

6. A molding die for a cylindrical composite material frame with a mortise and tenon structure as described in claim 1, characterized in that: The system includes baffles (5), a central shaft (8), and segmented truss blocks. Both ends of the central shaft (8) are provided with baffles (5), and the two baffles (5) are coaxially arranged with the central shaft (8). Multiple segmented truss blocks are arranged at equal intervals along the circumference of the central shaft (8). The segmented truss blocks are detachably connected to the central shaft (8) by bolts. A longitudinal channel (9) extending axially is formed between adjacent segmented truss blocks. The segmented truss blocks include multiple truss units spaced apart along the length of the central shaft (8). Each truss unit includes a central truss block (7) and two side trusses (6). The two sides of the central truss block (7) are connected to the side trusses (6) respectively. An annular channel (10) is formed between adjacent truss units. The cross-section of the annular channel (10) is a tapered structure that gradually narrows toward the central shaft (8).

7. The molding die for a cylindrical composite material frame with a mortise and tenon structure according to claim 6, characterized in that: The segmented truss assembly is connected to the central shaft (8) by bolts.

8. The molding die for a cylindrical composite material frame with a mortise and tenon structure according to claim 6, characterized in that: The baffle (5), the central shaft (8), and the segmented truss assembly are all made of metal.

9. A method for molding a cylindrical composite material frame with a mortise and tenon structure as described in claim 1, comprising the following steps: S1: The longitudinal rib (1) is molded using carbon fiber or glass fiber prepreg material, and a dovetail groove is machined at the connection position between the longitudinal rib (1) and the ring frame (2). S2: Install the longitudinal rib (1) in the longitudinal channel (9) of the forming mold; S3: The ring frame (2) is formed by wet winding of carbon fiber or glass fiber. By controlling the winding tension and the change of fiber layer width, the fiber-reinforced prepreg gradually widens on both sides of the intersection of the longitudinal ribs (1) and fills the dovetail groove from top to bottom for curing. S4: After curing, it forms an integral structure in which the longitudinal rib (1) and the ring frame (2) are connected by mortise and tenon joints; S5: The segmented separation mold assembly is used to demold, resulting in a cylindrical composite material frame with mortise and tenon structure.

10. The molding method of the cylindrical composite material frame with mortise and tenon structure according to claim 9, characterized in that: S5 also includes providing a skin (4) or not providing a skin (4) on the outer surface of a cylindrical composite material frame with a mortise and tenon structure.

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