Wet-state L-shaped composite stringer forming device and batch forming method

Abstract

The invention provides a wet-state L-shaped composite stringer forming device and a batch forming method. According to the method, a diaphragm device and a vacuum workbench assembly form a closed space, a plurality of stringer pre-forming molds and a plurality of flat-plate-shaped wet-state L-shaped composite stringer blanks are sealed in the closed space, and the stringer pre-forming molds and the flat-plate-shaped wet-state L-shaped composite stringer blanks are formed by controlling an infrared heating pipe in a heating assembly and a vacuum generator in the vacuum workbench assembly. And the closed space is heated and vacuumized, so that an elastic film in the diaphragm device deforms to bend and deform the flat-plate-shaped wet-state L-shaped composite stringer blank, the wet-state L-shaped composite stringer is formed, and batch forming of the wet-state L-shaped composite stringer is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft engine installation, in particular to a wet state L-shaped composite stringer forming device and a batch forming method. Background Art

[0002] Composite materials are widely used in a variety of military and civilian aircraft due to their numerous advantages, including high specific strength, high specific stiffness, and customizable performance. Aircraft wing panels, fuselage panels, horizontal tail panels, and vertical tail panels are often T-shaped reinforced panels, consisting of T-shaped stringers and skins. Fabrication of these composite T-stringers requires first laying down wet composite prepreg to form wet L-shaped composite stringers, which are then combined into a single wet T-shaped composite stringer.

[0003] At present, the domestic manufacturing of composite L-shaped long stringers is all done manually. First, the wet composite prepreg is laid layer by layer on the L-shaped long stringer mold. After every three layers, a bag is made and vacuumed to compact each layer and eliminate the gaps between layers. This composite L-shaped long stringer manufacturing method has low manufacturing efficiency, high labor intensity, requires a large number of workers, and has high manufacturing costs. With the improvement of aircraft performance, composite T-shaped reinforced wall panels are increasingly used in aircraft. The demand for composite T-shaped long stringers by various aircraft manufacturing units has greatly increased. In order to reduce the cost of aircraft manufacturing, it is necessary to significantly improve the manufacturing efficiency of wet L-shaped composite long stringers. However, there are few studies on the batch molding methods of wet L-shaped composite long stringers, the level is low, and there are no application examples. This has seriously delayed the overall manufacturing process of composite T-shaped reinforced wall panels. Therefore, in order to meet production needs, it is urgent to study a wet L-shaped composite long stringer molding device and batch molding method. Summary of the Invention

[0004] In order to solve practical production problems, the present invention provides a wet state L-shaped composite long stringer forming device and a batch forming method.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a wet state L-shaped composite long stringer forming device, which comprises: a lifting device, a heating component, a diaphragm device, a vacuum workbench component, and a long stringer preforming mold, the lifting device is placed on the ground; the heating component is installed inside the lifting device and can be accurately moved in the vertical direction under the drive of the lifting device; the diaphragm device is fixed to the lower part of the heating component; the vacuum workbench component is located directly below the diaphragm device and is installed on the ground; the long stringer preforming mold is placed on the upper surface of the vacuum workbench component for supporting the wet state composite long stringer blank; A flat-plate wet L-shaped composite long stringer blank is placed on the long stringer preforming mold, and the control system controls the lifting device to move downward, so that the diaphragm device covers the long stringer preforming mold and the wet L-shaped composite long stringer blank, and is completely fitted with the upper surface of the vacuum workbench assembly. The heating assembly and the vacuum workbench assembly are controlled to heat and vacuum the long stringer preforming mold and the wet L-shaped composite long stringer blank, and finally the flat-plate wet L-shaped composite long stringer blank is bent to completely fit the long stringer preforming mold to form a wet L-shaped composite long stringer, thereby realizing rapid prototyping of the wet L-shaped composite long stringer.

[0006] Preferably, the lifting device includes a group of fixed columns symmetrically arranged on the ground, two identical lifting mechanisms, two identical lifting platforms, a swinging mechanism, a swinging sliding mechanism, two identical connecting devices, and an in-frame crane. The two identical lifting mechanisms are installed on the opposite sides of the two fixed columns, and the lifting directions are parallel to each other and in the vertical direction. The side surfaces of the two lifting platforms are respectively fixed to the two groups of lifting mechanisms, and can move up and down in the vertical direction under the drive of the lifting mechanisms. The swinging mechanism and the swinging sliding mechanism are respectively installed on the upper surfaces of the two lifting platforms, and the swinging mechanism is parallel to the rotation axis of the swinging sliding mechanism. The two groups of connecting devices are relatively fixed on the swinging mechanism and the swinging sliding mechanism, and the in-frame crane spans above a group of fixed columns.

[0007] Preferably, the heating component includes a heating component fixing frame, a ventilation box, an infrared heating tube, a blower, and an exhaust fan. The heating component fixing frame is a truss structure, and its two ends are respectively fixed on two connecting devices of the lifting device. The ventilation box is a rectangular hollow structure, and the lower surface is provided with a plurality of vents arranged in a matrix, and a circular hole is provided at each end of the upper surface. A plurality of infrared heating tubes are arranged in a matrix and fixed on the lower surface of the ventilation box, and are arranged alternately with the vents on the lower surface of the ventilation box. The blower and exhaust fan are respectively installed on the upper surfaces at both ends of the ventilation box and connected to the circular holes at both ends.

[0008] Preferably, the diaphragm device includes a fixed frame, an elastic membrane, a pressing frame, and a locking mechanism. The fixed frame is a hollow circular structure with a circular groove around the edge of the lower surface. The upper surface is connected to the edge of the lower surface of the ventilation box in the heating assembly. The pressing frame is a circular plate structure with a certain thickness. The upper surface is provided with a circular boss that completely matches the circular groove on the lower surface of the fixed frame. It is fixed to the lower surface of the fixed frame by bolts. The elastic membrane is a rectangular rubber membrane with a certain elastic modulus. It is placed between the fixed frame and the pressing frame and is pressed by the pressing frame. Multiple locking mechanisms are evenly installed on both sides of the fixed frame along the length direction.

[0009] Preferably, the locking mechanism includes a base, a guide shaft, a compression spring, a guide rail A, a movable seat, a locking drive device, a locking bolt, and an upper locking seat. The base is a block structure, which is fixed to the side of the fixed frame of the diaphragm device. The two guide shafts are installed on both sides of the base in parallel with each other, and a compression spring is sleeved on them. The guide rail A is installed in the middle of the upper surface of the base and is parallel to the two guide shafts. The movable seat is installed on the upper surface of the slider of the guide rail and is connected to the two guide shafts. The locking drive device is installed on the movable seat. The locking bolt is connected to the locking drive device and can rotate under the drive of the locking drive device. The upper locking seat is a rectangular block structure with a through hole in the middle. It is fixed to the side of the fixed frame of the diaphragm device, directly below the base, and the locking bolt is in the middle through hole.

[0010] Preferably, the vacuum workbench assembly includes a workbench, a sealing ring, a temperature sensor, a support frame, a guide rail B, a rack, a mobile drive device, a vacuum generator, and a locking block. The workbench is a rectangular block structure, and a semicircular cross-section groove is opened on the edge of the upper surface. A plurality of mutually interconnected circular grooves are provided inside, and a plurality of through holes are evenly arranged on the internal circular grooves, which are located directly below the diaphragm device. The sealing ring is an O-type circular rubber sealing ring, which is installed in the semicircular circular groove on the upper surface of the workbench. A plurality of temperature sensors are evenly installed in the workbench, which can measure the temperature of the upper surface of the workbench in real time. The support frame is a truss structure, which is installed on the lower surface of the workbench. The surface is used to support the work surface. Multiple guide rails B are evenly fixed to the ground along the width direction of the work surface and are parallel to each other. The slider on the guide rail B is connected to the lower surface of the support frame. The rack is fixed to the ground parallel to the guide rail B. The mobile drive device is installed on the support frame, and the support frame and the work surface can be driven to move along the guide rail B through the rack. The vacuum generator is fixed inside the support frame and is connected to the through hole in the circular groove on the work surface through the air pipe. The locking block is a square block structure with a threaded hole in the middle. Multiple locking blocks are fixed and evenly installed on both sides of the work surface along the length direction, and the threaded holes on the locking blocks are aligned with the through holes on the upper locking seat in the locking mechanism.

[0011] Preferably, the long stringer preforming mold is a rectangular cavity structure made of steel, with an opening at the bottom and a plurality of reinforcing ribs provided inside the cavity. An L-shaped groove is provided at the intersection of the upper surface and the side surface, and the groove shape and size are consistent with the L-shaped composite long stringer product.

[0012] The present invention also provides a method for batch forming the above-mentioned wet-state L-shaped composite long stringer, comprising the following steps: 1. Use a composite material automatic tape laying machine to lay the prepreg on a flat plate mold to form a composite flat plate of specified thickness, and cut it into multiple long strips of composite flat plates of specified size to form multiple flat-plate wet L-shaped composite long stringer blanks; 2. Transporting multiple long stringer preforming molds and multiple flat wet L-shaped composite long stringer blanks to the vicinity of the vacuum workbench assembly; 3. Control the movement of the mobile drive device in the vacuum workbench assembly to drive the entire vacuum workbench assembly to move along the guide rail B so that it is outside the diaphragm device; 4. Use the crane in the lifting device to place multiple long stringer preforming molds on the work surface of the vacuum workbench assembly at intervals. Place multiple flat-plate wet L-shaped composite long stringer blanks in the corresponding grooves on the upper surface of the long stringer preforming molds in sequence according to regulations and secure them with tape. At this time, part of the flat-plate wet L-shaped composite long stringer blank is in the groove, and the other part is suspended outside the long stringer preforming mold. 5. Control the movement of the moving drive device in the vacuum workbench assembly to drive the vacuum workbench assembly, multiple long stringer preforming molds, and multiple flat-plate wet L-shaped composite long stringer blanks to move along the guide rail B so that they are directly below the diaphragm device; 6. Control the two lifting mechanisms in the lifting device to move downward synchronously until the lower surface of the diaphragm device contacts the sealing ring in the vacuum workbench assembly and compresses and deforms the sealing ring, so that the elastic membrane in the diaphragm device seals the multiple long stringer preforming molds and the multiple flat-plate wet L-shaped composite long stringer blanks to the upper surface of the vacuum workbench assembly; 7. Simultaneously control the movement of the locking drive devices of multiple locking mechanisms, drive the locking bolts to rotate into the threaded holes of the locking blocks in the vacuum workbench assembly, and lock the diaphragm device and the vacuum workbench assembly; 8. In accordance with specified parameters and procedures, the plurality of long stringer preforming molds and the plurality of flat-plate wet L-shaped composite long stringer blanks are heated by the infrared heating tubes in the heating assembly, and the enclosed space formed by the upper surface of the vacuum workbench assembly and the lower surface of the diaphragm device is evacuated by the vacuum generator in the vacuum workbench assembly, so that the elastic membrane in the diaphragm device is deformed to bend and deform the flat-plate wet L-shaped composite long stringer blanks until they are completely fitted into the L-shaped grooves on the long stringer preforming molds; 9. Maintaining the specified temperature and pressure for a certain period of time, the flat wet L-shaped composite long stringer blank is turned into an L-shape without rebound; 10. Control the infrared heating tube in the heating assembly to stop working, turn on the blower and exhaust fan, reduce the temperature of the vacuum workbench assembly and the diaphragm device to room temperature, control the vacuum generator in the vacuum workbench assembly to stop working, so that the air pressure in the closed space formed by the upper surface of the vacuum workbench assembly and the lower surface of the diaphragm device is consistent with the outside world, and the elastic membrane in the diaphragm device returns to its initial state.

[0013] 11. Simultaneously control the movement of the locking drive devices of multiple locking mechanisms, drive the locking bolts to rotate and withdraw from the threaded holes of the locking blocks in the vacuum workbench assembly, thereby unlocking the diaphragm device and the vacuum workbench assembly; 12 Control the two lifting mechanisms in the lifting device to move upward synchronously, so that the diaphragm device is completely separated from the multiple long stringer preforming molds and the wet state L-shaped composite long stringer, control the movement of the mobile drive device in the vacuum workbench assembly, drive the entire vacuum workbench assembly to move along the guide rail B, so that it is outside the diaphragm device, and use the internal crane in the lifting device to lift the multiple long stringer preforming molds and the wet state L-shaped composite long stringer from the upper surface of the vacuum workbench assembly in sequence, thereby realizing batch molding of the wet state L-shaped composite long stringers.

[0014] Beneficial effects: The present invention provides a wet state L-shaped composite long stringer forming device and a batch forming method. The method forms a closed space through a diaphragm device and a vacuum workbench assembly, and seals a plurality of long stringer preforming molds and a plurality of flat-plate wet state L-shaped composite long stringer blanks in the closed space. By controlling the infrared heating tube in the heating assembly and the vacuum generator in the vacuum workbench assembly, the closed space is heated and evacuated respectively, so that the elastic membrane in the diaphragm device is deformed to bend and deform the flat-plate wet state L-shaped composite long stringer blank to form a wet state L-shaped composite long stringer, thereby realizing the batch forming of wet state L-shaped composite long stringers. The device is simple in form and safe and reliable in operation. It can greatly improve the manufacturing efficiency of wet state L-shaped composite long strings and reduce manufacturing costs, which has great positive significance for the manufacture of wet state L-shaped composite long strings. It can be directly extended to the application of similar composite parts manufacturing fields in other industries.

[0015] The present invention is further described in detail below with reference to the accompanying drawings: BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 Schematic diagram of the wet state L-shaped composite long stringer forming device; Figure 2 Schematic diagram of a long stringer blank supported by a long stringer preforming die; Figure 3 Schematic diagram of the lifting device structure; Figure 4Schematic diagram of the heating component structure; Figure 5 Schematic diagram of the diaphragm device structure; Figure 6 Schematic diagram of the locking mechanism structure; Figure 7 Schematic diagram of the vacuum workbench assembly structure; Figure 8 Cross-sectional view of the vacuum table assembly; Figure 9 Schematic diagram of the long stringer preforming mold structure; Explanation of numbers in the figure: 1 wet state L-shaped composite long stringer blank, 2 lifting device, 3 heating assembly, 4 diaphragm device, 5 vacuum workbench assembly, 6 long stringer preforming mold, 7 fixed column, 8 lifting mechanism, 9 lifting platform, 10 swing mechanism, 11 swing sliding mechanism, 12 connecting device, 13 crane in the frame, 14 heating assembly fixed frame, 15 ventilation box, 16 infrared heating tube, 17 blower, 18 exhaust fan, 19 fixed frame, 20 elastic membrane, 21 pressing frame, 22 locking mechanism, 23 base, 24 guide shaft, 25 compression spring, 26 guide rail A, 27 moving seat, 28 locking drive device, 29 locking bolt, 30 upper locking seat, 31 work table, 32 sealing ring, 33 temperature sensor, 34 support frame, 35 guide rail B, 36 rack, 37 moving drive device, 38 vacuum generator, 39 locking block. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be described in detail below in conjunction with embodiments.

[0017] See also Figure 1 、 2As shown, this embodiment provides a wet state L-shaped composite long stringer forming device, which includes: a lifting device 2, a heating component 3, a diaphragm device 4, a vacuum workbench component 5, and a long stringer preforming mold 6. The lifting device 2 is placed on the ground; the heating component 3 is installed inside the lifting device 2 and can be accurately moved in the vertical direction under the drive of the lifting device 2; the diaphragm device 4 is fixed to the lower part of the heating component 3; the vacuum workbench component 5 is located directly below the diaphragm device 4 and is installed on the ground; the long stringer preforming mold 6 is placed on the upper surface of the vacuum workbench component 5 to support the wet state composite long stringer blank; the flat plate-shaped wet The wet L-shaped composite long stringer blank 1 is placed on the long stringer preforming mold 6, and the control system controls the lifting device 2 to move downward, so that the diaphragm device 4 covers the long stringer preforming mold 6 and the wet L-shaped composite long stringer blank 1, and is completely fitted with the upper surface of the vacuum workbench assembly 5. The heating assembly 3 and the vacuum workbench assembly 5 are controlled to heat and vacuum the long stringer preforming mold 6 and the wet L-shaped composite long stringer blank 1, and finally the flat-plate wet L-shaped composite long stringer blank 1 is bent and completely fitted with the long stringer preforming mold 6 to form a wet L-shaped composite long stringer, thereby realizing rapid prototyping of the wet L-shaped composite long stringer.

[0018] See also Figure 3 As shown, the lifting device 2 is used to move the heating component 3 up and down accurately.

[0019] It includes a group of fixed columns 7 symmetrically arranged on the ground, two identical lifting mechanisms 8, two identical lifting platforms 9, a swinging mechanism 10, a swinging sliding mechanism 11, two identical connecting devices 12, and an in-frame crane 13. The two identical lifting mechanisms 8 are installed on the opposite sides of the two fixed columns 7, and the lifting directions are parallel to each other and in the vertical direction. The sides of the two lifting platforms 9 are respectively fixed to the two groups of lifting mechanisms 8, and can move up and down in the vertical direction under the drive of the lifting mechanisms 8. The swinging mechanism 10 and the swinging sliding mechanism 11 are respectively installed on the upper surfaces of the two lifting platforms 9, and the swinging mechanism 10 is parallel to the rotation axis of the swinging sliding mechanism 11. The two groups of connecting devices 12 are relatively fixed on the swinging mechanism 10 and the swinging sliding mechanism 11, respectively. The in-frame crane 13 spans above a group of fixed columns 7.

[0020] See also Figure 4As shown, the heating component 3 includes a heating component fixing frame 14, a ventilation box 15, an infrared heating tube 16, a blower 17, and an exhaust fan 18. The heating component fixing frame 14 is a truss structure, and its two ends are respectively fixed on the two connecting devices 12 of the lifting device 2. The ventilation box 15 is a rectangular hollow structure, and the lower surface is provided with a plurality of vents arranged in a matrix, and the upper surface is provided with a circular hole at each end. A plurality of infrared heating tubes 16 are arranged in a matrix and fixed on the lower surface of the ventilation box 15, and are arranged alternately with the vents on the lower surface of the ventilation box 15. The blower 17 and the exhaust fan 18 are respectively installed on the upper surfaces at both ends of the ventilation box 15 and connected to the circular holes at both ends.

[0021] See also Figure 5 As shown, the diaphragm device 4 includes a fixed frame 19, an elastic membrane 20, a pressing frame 21, and a locking mechanism 22. The fixed frame 19 is a hollow circular structure with a circular groove around the edge of the lower surface. The upper surface is connected to the edge of the lower surface of the ventilation box 15 in the heating component 3. The pressing frame 21 is a circular plate structure with a certain thickness. The upper surface is provided with a circular boss that completely matches the circular groove on the lower surface of the fixed frame 19. It is fixed to the lower surface of the fixed frame 19 by bolts. The elastic membrane 20 is a rectangular rubber membrane with a certain elastic modulus. It is placed between the fixed frame 19 and the pressing frame 21 and is pressed by the pressing frame 21. Multiple locking mechanisms 22 are evenly installed on both sides of the fixed frame 19 along the length direction.

[0022] See also Figure 6 As shown, the locking mechanism 22 includes a base 23, a guide shaft 24, a compression spring 25, a guide rail A26, a movable seat 27, a locking drive device 28, a locking bolt 29, and an upper locking seat 30. The base 23 is a block structure, which is fixed to the side of the fixed frame 19 of the diaphragm device 4. The two guide shafts 24 are installed on both sides of the base 23 in parallel with each other, and a compression spring 25 is sleeved on it. The guide rail A26 is installed in the middle of the upper surface of the base 23 and is parallel to the two guide shafts 24. The movable seat 27 is installed on the upper surface of the slider of the guide rail and is connected to the two guide shafts 24. The locking drive device 28 is installed on the movable seat 27. The locking bolt 29 is connected to the locking drive device 28 and can rotate under the drive of the locking drive device 28. The upper locking seat 30 is a rectangular block structure with a through hole in the middle. It is fixed to the side of the fixed frame 19 of the diaphragm device 4, at one end of the base 23, and the locking bolt 29 is in the through hole in the middle of the base 23.

[0023] See also Figure 7 、 8As shown, the vacuum workbench assembly 5 includes a workbench 31, a sealing ring 32, a temperature sensor 33, a support frame 34, a guide rail B35, a rack 36, a mobile drive device 37, a vacuum generator 38, and a locking block 39. The workbench 31 is a rectangular block structure, and a semicircular cross-section groove is opened on the edge of the upper surface. The interior of the workbench 31 is provided with a plurality of mutually connected circular grooves, and a plurality of through holes are evenly arranged on the internal circular grooves, which are located directly below the diaphragm device 4. The sealing ring 32 is an O-type circular rubber sealing ring 32, which is installed in the semicircular circular groove on the upper surface of the workbench 31. A plurality of temperature sensors 33 are evenly installed in the workbench 31, which can measure the temperature of the upper surface of the workbench 31 in real time. The support frame 34 is a truss structure, which is installed on the workbench 31. The lower surface is used to support the work table 31. Multiple guide rails B35 are evenly fixed to the ground along the width direction of the work table 31 and are parallel to each other. The slider on the guide rail B35 is connected to the lower surface of the support frame 34. The rack 36 is fixed to the ground parallel to the guide rail B35. The mobile drive device 37 is installed on the support frame 34, and can drive the support frame 34 and the work table 31 to move along the guide rail B35 through the rack 36. The vacuum generator 38 is fixed inside the support frame 34 and is connected to the through hole in the circular groove on the work table 31 through the air pipe. The locking block 39 is a square block structure with a threaded hole in the middle. Multiple locking blocks 39 are evenly installed on both sides of the work table 31 along the length direction, and the threaded holes on the locking blocks 39 are aligned with the through holes on the upper locking seat 30 in the locking mechanism 22.

[0024] See also Figure 9 As shown, the long stringer preforming mold 6 is a rectangular cavity structure made of steel with an opening at the bottom. A plurality of reinforcing ribs are provided inside the cavity. An L-shaped groove is provided at the intersection of the upper surface and the side surface. The groove shape and size are consistent with the L-shaped composite long stringer product.

[0025] The above-mentioned method for batch forming of wet-state L-shaped composite long stringers comprises the following steps: 1. Using a composite material automatic tape laying machine, the prepreg is laid on a flat plate mold to form a composite flat plate of a specified thickness, and then cut into a plurality of long strips of composite flat plates of a specified size, forming a plurality of flat wet L-shaped composite long stringer blanks 1; 2. Transporting a plurality of long stringer preforming molds 6 and a plurality of flat wet L-shaped composite long stringer blanks 1 to the vicinity of the vacuum workbench assembly 5; 3. Control the movement of the moving drive device 37 in the vacuum workbench assembly 5 to drive the entire vacuum workbench assembly 5 to move along the guide rail B35 so that it is outside the diaphragm device 4; Multiple stringer preforming molds 6 are placed on the work surface 31 of the vacuum workbench assembly 5 at intervals by the crane 13 in the lifting device 2. Multiple flat-plate wet L-shaped composite stringer blanks 1 are sequentially placed in the corresponding grooves on the upper surface of the stringer preforming molds 6 according to regulations and secured with tape. At this time, part of the flat-plate wet L-shaped composite stringer blanks 1 is in the grooves, while the other part is suspended outside the stringer preforming mold 6. 5 controls the movement of the moving drive device 37 in the vacuum workbench assembly 5, driving the vacuum workbench assembly 5, the plurality of long stringer preforming molds 6, and the plurality of flat-plate wet L-shaped composite long stringer blanks 1 to move along the guide rail B35 so that they are directly below the diaphragm device 4; 6. Control the two lifting mechanisms 8 in the lifting device 2 to move downward synchronously until the lower surface of the diaphragm device 4 contacts the sealing ring 32 in the vacuum workbench assembly 5, and compresses and deforms the sealing ring 32, so that the elastic membrane 20 in the diaphragm device 4 seals the multiple long stringer preforming molds 6 and the multiple flat-plate wet L-shaped composite long stringer blanks 1 on the upper surface of the vacuum workbench assembly 5; 7. Simultaneously control the movement of the locking drive devices 28 of the multiple locking mechanisms 22, driving the locking bolts 29 to rotate into the threaded holes of the locking blocks 39 in the vacuum workbench assembly 5, thereby locking the diaphragm device 4 and the vacuum workbench assembly 5; 8. In accordance with specified parameters and procedures, the plurality of long stringer preforming molds 6 and the plurality of flat-plate wet L-shaped composite long stringer blanks 1 are heated by the infrared heating tubes 16 in the heating assembly 3. The enclosed space formed by the upper surface of the vacuum workbench assembly 5 and the lower surface of the diaphragm device 4 is evacuated by the vacuum generator 38 in the vacuum workbench assembly 5, causing the elastic membrane 20 in the diaphragm device 4 to deform and bend the flat-plate wet L-shaped composite long stringer blanks 1 until they are completely fitted into the L-shaped grooves of the long stringer preforming mold 6. 9. Maintaining the L-shaped composite stringer blank 1 in a flat wet state at a specified temperature and pressure for a specified time to form an L-shape without causing springback; 10 controls the infrared heating tube 16 in the heating assembly 3 to stop working, turns on the blower 17 and the exhaust fan 18, reduces the temperature of the vacuum workbench assembly 5 and the diaphragm device 4 to room temperature, controls the vacuum generator 38 in the vacuum workbench assembly 5 to stop working, makes the air pressure in the closed space formed by the upper surface of the vacuum workbench assembly 5 and the lower surface of the diaphragm device 4 consistent with the outside, and the elastic membrane 20 in the diaphragm device 4 returns to its initial state.

[0026] 11 simultaneously controls the movement of the locking drive devices 28 of the multiple locking mechanisms 22, driving the locking bolts 29 to rotate and withdraw from the threaded holes of the locking blocks 39 in the vacuum workbench assembly 5, thereby unlocking the diaphragm device 4 and the vacuum workbench assembly 5; 12 controls the two lifting mechanisms 8 in the lifting device 2 to move upward synchronously, so that the diaphragm device 4 is completely separated from the multiple long stringer preforming molds 6 and the wet state L-shaped composite long stringer. The movement of the mobile drive device 37 in the vacuum workbench assembly 5 is controlled to drive the entire vacuum workbench assembly 5 to move along the guide rail B35 so that it is outside the diaphragm device 4. The internal crane 13 in the lifting device 2 is used to lift the multiple long stringer preforming molds 6 and the wet state L-shaped composite long stringer from the upper surface of the vacuum workbench assembly 5 in sequence, thereby realizing batch molding of the wet state L-shaped composite long stringers.

[0027] An embodiment of the present invention uses a set of devices combined with a batch molding method to achieve batch molding of wet L-shaped composite long stringers; a closed space is formed by a diaphragm device and a vacuum workbench assembly, and multiple long stringer preforming molds and multiple flat-plate wet L-shaped composite long stringer blanks are sealed in the closed space. By controlling the infrared heating tube in the heating assembly and the vacuum generator in the vacuum workbench assembly, the closed space is heated and vacuumed respectively, so that the elastic membrane in the diaphragm device is deformed to bend and deform the flat-plate wet L-shaped composite long stringer blanks to form wet L-shaped composite long stringers.

[0028] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A wet state L-shaped composite long stringer forming device, characterized in that: The forming device comprises: a lifting device placed on the ground; The heating component is installed inside the lifting device and can be accurately moved in the vertical direction under the drive of the lifting device; a diaphragm device fixed to the lower portion of the heating assembly; A vacuum workbench assembly, which is located directly below the diaphragm device and is installed on the ground; A long stringer preforming mold is placed on the upper surface of the vacuum workbench assembly and is used to support the wet composite long stringer blank; A flat-plate wet L-shaped composite long stringer blank is placed on the long stringer preforming mold, and the control system controls the lifting device to move downward so that the diaphragm device covers the long stringer preforming mold and the wet L-shaped composite long stringer blank and is completely fitted with the upper surface of the vacuum workbench assembly. The heating assembly and the vacuum workbench assembly are controlled to heat and vacuum the long stringer preforming mold and the wet L-shaped composite long stringer blank, and finally the flat-plate wet L-shaped composite long stringer blank is bent to completely fit the long stringer preforming mold to form a wet L-shaped composite long stringer, thereby realizing rapid prototyping of the wet L-shaped composite long stringer.

2. The wet state L-shaped composite stringer forming device according to claim 1, characterized in that: The lifting device includes a group of fixed columns symmetrically arranged on the ground, two identical lifting mechanisms, two identical lifting platforms, a swinging mechanism, a swinging sliding mechanism, two identical connecting devices, and an in-frame crane. The two identical lifting mechanisms are installed on the opposite sides of the two fixed columns, and the lifting directions are parallel to each other and in the vertical direction. The side surfaces of the two lifting platforms are respectively fixed to the two groups of lifting mechanisms, and can move up and down in the vertical direction under the drive of the lifting mechanisms. The swinging mechanism and the swinging sliding mechanism are respectively installed on the upper surfaces of the two lifting platforms, and the swinging mechanism is parallel to the rotation axis of the swinging sliding mechanism. The two groups of connecting devices are relatively fixed on the swinging mechanism and the swinging sliding mechanism, and the in-frame crane spans above a group of fixed columns.

3. The wet state L-shaped composite stringer forming device according to claim 1, characterized in that: The heating component includes a heating component fixing frame, a ventilation box, an infrared heating tube, a blower, and an exhaust fan. The heating component fixing frame is a truss structure, and its two ends are respectively fixed on the two connecting devices of the lifting device. The ventilation box is a rectangular hollow structure, and the lower surface is provided with multiple vents arranged in a matrix, and a circular hole is provided at each end of the upper surface. Multiple infrared heating tubes are arranged in a matrix and fixed on the lower surface of the ventilation box, and are arranged alternately with the vents on the lower surface of the ventilation box. The blower and exhaust fan are respectively installed on the upper surfaces at both ends of the ventilation box and connected to the circular holes at both ends.

4. The wet state L-shaped composite stringer forming device according to claim 1, characterized in that: The diaphragm device includes a fixed frame, an elastic membrane, a pressing frame, and a locking mechanism. The fixed frame is a hollow circular structure with a circular groove around the edge of the lower surface. Its upper surface is connected to the edge of the lower surface of the ventilation box in the heating assembly. The pressing frame is a circular plate structure with a certain thickness. The upper surface is provided with a circular boss that completely matches the circular groove on the lower surface of the fixed frame. It is fixed to the lower surface of the fixed frame by bolts. The elastic membrane is a rectangular rubber membrane with a certain elastic modulus. It is placed between the fixed frame and the pressing frame and is pressed by the pressing frame. Multiple locking mechanisms are evenly installed on both sides of the fixed frame along the length direction.

5. The wet state L-shaped composite stringer forming device according to claim 4, characterized in that: The locking mechanism includes a base, a guide shaft, a compression spring, a guide rail A, a movable seat, a locking drive device, a locking bolt, and an upper locking seat. The base is a block structure, which is fixed to the side of the fixed frame of the diaphragm device. The two guide shafts are installed on both sides of the base in parallel with each other, and a compression spring is sleeved on them. The guide rail A is installed in the middle of the upper surface of the base and is parallel to the two guide shafts. The movable seat is installed on the upper surface of the slider of the guide rail and is connected to the two guide shafts. The locking drive device is installed on the movable seat. The locking bolt is connected to the locking drive device and can rotate under the drive of the locking drive device. The upper locking seat is a rectangular block structure with a through hole in the middle. It is fixed to the side of the fixed frame of the diaphragm device, at one end of the base, and the locking bolt is in the central through hole.

6. The wet state L-shaped composite stringer forming device according to claim 1, characterized in that: The vacuum workbench assembly includes a workbench, a sealing ring, a temperature sensor, a support frame, a guide rail B, a rack, a mobile drive device, a vacuum generator, and a locking block. The workbench is a rectangular block structure, and a semicircular groove with a cross section is opened on the edge of the upper surface. A plurality of mutually interconnected grooves are provided inside. A plurality of through holes are evenly arranged on the inner grooves, which are located directly below the diaphragm device. The sealing ring is an O-type rubber sealing ring, which is installed in the semicircular groove on the upper surface of the workbench. A plurality of temperature sensors are evenly installed in the workbench, which can measure the temperature of the upper surface of the workbench in real time. The support frame is a truss structure, which is installed under the workbench. The surface is used to support the work surface. Multiple guide rails B are evenly fixed to the ground along the width direction of the work surface and are parallel to each other. The slider on the guide rail B is connected to the lower surface of the support frame. The rack is fixed to the ground parallel to the guide rail B. The mobile drive device is installed on the support frame, and the support frame and the work surface can be driven to move along the guide rail B through the rack. The vacuum generator is fixed inside the support frame and is connected to the through hole in the circular groove on the work surface through the air pipe. The locking block is a square block structure with a threaded hole in the middle. Multiple locking blocks are evenly installed on both sides of the work surface along the length direction, and the threaded holes on the locking blocks are aligned with the through holes on the upper locking seat in the locking mechanism.

7. The wet state L-shaped composite stringer forming device according to claim 1, characterized in that: The long stringer preforming mold is a rectangular cavity structure made of steel with an opening at the bottom. A plurality of reinforcing ribs are provided inside the cavity. An L-shaped groove is provided at the intersection of the upper surface and the side surface. The groove shape and size are consistent with the L-shaped composite long stringer product.

8. A method for batch forming L-shaped composite long stringers in a wet state, implemented using the forming device according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: S1, using a composite material automatic tape laying machine to lay the prepreg on a flat plate mold into a composite flat plate of a specified thickness, and then cut it into a plurality of long strips of composite flat plates of specified sizes to form a plurality of flat-plate wet L-shaped composite long stringer blanks; S2, transporting a plurality of long stringer preforming molds and a plurality of flat wet L-shaped composite long stringer blanks to the vicinity of the vacuum workbench assembly; S3, controlling the movement of the moving drive device in the vacuum workbench assembly to drive the entire vacuum workbench assembly to move along the guide rail B so that it is outside the diaphragm device; S4, using the crane in the frame of the lifting device to place multiple long stringer preforming molds at intervals on the work surface of the vacuum workbench assembly, and sequentially placing multiple flat-plate wet L-shaped composite long stringer blanks in the corresponding grooves on the upper surface of the long stringer preforming molds according to regulations and securing them with tape. At this time, part of the flat-plate wet L-shaped composite long stringer blank is in the groove, and the other part is suspended outside the long stringer preforming mold; S5, controlling the movement of the moving drive device in the vacuum workbench assembly to drive the vacuum workbench assembly, the multiple long stringer preforming molds, and the multiple flat-plate wet L-shaped composite long stringer blanks to move along the guide rail B so that they are directly below the diaphragm device; S6, controlling the two lifting mechanisms in the lifting device to move downward synchronously until the lower surface of the diaphragm device contacts the sealing ring in the vacuum workbench assembly and compresses and deforms the sealing ring, so that the elastic membrane in the diaphragm device seals the multiple long stringer preforming molds and the multiple flat-plate wet L-shaped composite long stringer blanks to the upper surface of the vacuum workbench assembly; S7, simultaneously controlling the movement of the locking drive devices of the multiple locking mechanisms to drive the locking bolts to rotate into the threaded holes of the locking blocks in the vacuum workbench assembly, thereby locking the diaphragm device and the vacuum workbench assembly; S8, heating the plurality of stringer preforming molds and the plurality of flat-plate wet L-shaped composite stringer blanks using infrared heating tubes in the heating assembly in accordance with specified parameters and procedures, and evacuating the enclosed space formed by the upper surface of the vacuum workbench assembly and the lower surface of the diaphragm assembly using a vacuum generator in the vacuum workbench assembly, causing the elastic membrane in the diaphragm assembly to deform and bend the flat-plate wet L-shaped composite stringer blanks until they are completely fitted into the L-shaped grooves of the stringer preforming molds; S9, maintaining the specified temperature and pressure for a certain period of time, so that the flat wet L-shaped composite long stringer blank becomes L-shaped without rebound; S10, controlling the infrared heating tube in the heating assembly to stop working, turning on the blower and exhaust fan, lowering the temperature of the vacuum workbench assembly and the diaphragm device to room temperature, controlling the vacuum generator in the vacuum workbench assembly to stop working, so that the air pressure in the closed space formed by the upper surface of the vacuum workbench assembly and the lower surface of the diaphragm device is consistent with that of the outside world, and the elastic membrane in the diaphragm device returns to its initial state. S11, simultaneously controlling the movement of the locking drive devices of the multiple locking mechanisms to drive the locking bolts to rotate and withdraw from the threaded holes of the locking blocks in the vacuum workbench assembly, thereby unlocking the diaphragm device and the vacuum workbench assembly; 8-12 Control the two lifting mechanisms in the lifting device to move upward synchronously, so that the diaphragm device is completely separated from the multiple long stringer preforming molds and the wet state L-shaped composite long stringer, control the movement of the mobile drive device in the vacuum workbench assembly, and drive the entire vacuum workbench assembly to move along the guide rail B so that it is outside the diaphragm device. Use the crane in the frame of the lifting device to lift the multiple long stringer preforming molds and the wet state L-shaped composite long stringer from the upper surface of the vacuum workbench assembly in sequence to achieve batch molding of the wet state L-shaped composite long stringers.

Images