High-quality assembly and connection integration method for large-size skin and complex skeleton structure

Abstract

The invention discloses a high-quality assembly and connection integration method for a large-size skin and a complex framework structure, and relates to a connection method for the large-size skin and the framework structure. The invention aims to solve the problems of difficulty in mounting, misalignment in positioning, weak connection strength and easiness in causing distortion or out-of-tolerance of large-size airfoil skins such as rudder wings and wings of an existing aircraft and a complex skeleton structure. The method comprises the following steps: 1, manufacturing bolts of a skeleton structure; 2, positioning and punching of a large-size skin plate surface; and 3, assembling and connecting the large-size skin plate surface and the framework. The method is used for high-quality assembly and connection integration of the large-size skin and the complex framework structure.

Description

Technical Field

[0001] The present invention relates to a connection method for a large-sized skin and a framework structure. Background Art

[0002] In the modern aerospace field, the demand for lightweight wings and control surfaces is becoming increasingly urgent. Complex multi-layer structures including large-sized wing surfaces are widely used, which can not only provide heat insulation but also have good lightweight performance. Currently, such complex multi-layer structures use a framework to support and connect the wing skin. However, as the thickness of the multi-layer structure becomes thinner and thinner, the large-sized skin cannot be disassembled to ensure integrity, and there are many and dense contact points between the complex framework and the skin, resulting in difficult installation and inaccurate positioning. The assembly and high-quality connection of the large-sized skin and the complex framework structure have become increasingly difficult.

[0003] Traditional riveting and screwing methods have problems of failure and insecure connection; when using welding, firstly, there is insufficient welding strength, and secondly, welding is likely to cause deformation of the framework. When there are many welding points, it is impossible to ensure the positioning of the complex framework structure and the skin, and it is easy to cause distortion or out-of-tolerance.

[0004] Therefore, how to achieve the precise assembly and connection of a large-sized skin and a complex framework structure is the key to realizing the manufacture of the wing skin of an aircraft. Summary of the Invention

[0005] The present invention aims to solve the problems of difficult installation, inaccurate positioning, weak connection strength, easy distortion or out-of-tolerance of large-sized wing surface skins such as control surfaces and wings of existing aircraft, and further provides a high-quality assembly and connection integration method for a large-sized skin and a complex framework structure.

[0006] A high-quality assembly and connection integration method for a large-sized skin and a complex framework structure is carried out according to the following steps:

[0007] I. Manufacture of the dowel pin of the framework structure:

[0008] Process the end face of the framework structure in contact with the large-sized skin board surface to form a dowel pin structure, and the framework end face where the dowel pin structure is located is a dowel pin platform, obtaining a framework structure provided with a dowel pin structure;

[0009] II. Positioning punching of the large-sized skin board surface:

[0010] Perform punching treatment on the large-sized skin board surface, and then polish the punched hole to be smooth, obtaining the punched skin board surface;

[0011] The punching position and shape are consistent with the dowel pin structure;

[0012] III. Assembly and connection of the large-sized skin board surface and the framework;

[0013] Place one side of the punched skin panel surface parallel above the frame structure with a pin structure, align the punching positions on the skin panel surface with the positions of the pin structure, then insert the pin structure into the punched holes on the skin panel surface, and use the penetration welding process to tightly combine the pin structure and the pin platform with the skin panel surface on the other side of the skin panel surface. Finally, cut off the pin structure protruding from the skin panel surface and polish it, thus completing the high-quality assembly and connection of the large-size skin and the complex frame structure.

[0014] The beneficial effects of the present invention are as follows:

[0015] Compared with the existing connection methods for large-size skin panel surfaces and complex frame structures, through the special design of the pin structure, the present invention simplifies the process and reduces costs while greatly improving the connection accuracy, making the frame fit more closely with the outer skin panel surfaces of the wing and rudder wing, and ensuring that the frame will not shift in position due to stress and deformation. The structure of the frame is better preserved, and the task of transmitting stress can be better achieved, enabling the connected rudder wing or wing to withstand greater loads.

[0016] Compared with the existing connection methods for large-size skin panel surfaces and complex frame structures, the present invention changes the screw and nut connection to penetration welding, greatly improving the connection strength, making the connected panel surface smoother, and at the same time avoiding the problems of connection instability caused by the shedding of screws and nuts due to thermal expansion and long-term corrosion in the alternating high and low temperature environment. The connected structure can be applied to a wider and more demanding service environment.

[0017] The present invention can achieve the high-precision and high-strength assembly and connection of large-size skin panel surfaces and complex frame structures in rudder wings and wings. While simplifying the process and reducing costs, it greatly improves the connection accuracy and connection strength of the structure, and further reduces the high-temperature resistance and corrosion resistance of the connected components, with a wider application.

[0018] In addition to the large-size skin and complex support frame structure for the wing surface of aerospace aircraft mentioned above, the present invention is also applicable to other fields, such as seagoing ships or rockets, etc., which involve the high-precision and high-quality assembly and connection of large-size skin panel surfaces and complex internal frames.

[0019] The present invention relates to a method for the high-quality integrated assembly and connection of a large-size skin and a complex frame structure. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the assembly of the large-size skin panel surface and the frame structure in Step 3 of the specific implementation manner;

[0021] Figure 2 It is a schematic structural diagram of the punched skin panel surface prepared in Step 2 of the specific implementation manner;

[0022] Figure 3 It is a schematic diagram of the integrated process of high-quality assembly and connection of a large-sized skin and a complex framework structure in the first specific embodiment;

[0023] Figure 4 It is a schematic diagram of the structure in the sixth specific embodiment where the edge of the contact surface between the pin structure and the pin platform is located within the pin platform;

[0024] Figure 5 It is a schematic diagram of the structure in the sixth specific embodiment where the end face of the framework where the pin structure is located is divided into multiple pin platforms by the pin structure;

[0025] Figure 6 It is a schematic diagram of the threaded connection between the pin structure and the framework structure in the seventh specific embodiment;

[0026] Figure 7 It is a physical picture of the assembly and connection of the framework structure, the pin structure and the large-sized skin board surface in the first embodiment;

[0027] Figure 8 It is a physical picture of the skin board surface after the high-quality assembly and connection of the large-sized skin and the complex framework structure are completed in the first embodiment;

[0028] Figure 9 It is a physical picture of the connection by ordinary welding in the first comparative example. Specific Embodiments

[0029] The technical solution of the present invention is not limited to the specific embodiments listed below, and also includes any combination between the specific embodiments.

[0030] Specific Embodiment 1, in combination with Figures 1 to 3 Specific description: A method for high-quality assembly and connection integration of a large-sized skin and a complex framework structure in this embodiment is carried out according to the following steps:

[0031] 1. Manufacturing of pins for the framework structure:

[0032] A pin structure is machined on the end face of the framework structure in contact with the large-sized skin board surface, and the end face of the framework where the pin structure is located is a pin platform, obtaining a framework structure provided with a pin structure;

[0033] 2. Positioning and punching of the large-sized skin board surface:

[0034] The large-sized skin board surface is punched, and then the punched holes are polished to be smooth, obtaining the punched skin board surface;

[0035] The positions and shapes of the punched holes are consistent with the pin structure;

[0036] 3. Assembly and connection of the large-sized skin board surface and the framework;

[0037] Place one side of the skinned panel surface after punching parallel above the frame structure with a pin structure, so that the punching positions on the skinned panel surface correspond to the positions of the pin structure. Then insert the pin structure into the punched holes on the skinned panel surface. Using the penetration welding process, tightly combine the pin structure and the pin platform with the skinned panel surface on the other side of the skinned panel surface. Finally, cut off the pin structure that penetrates the skinned panel surface and polish it, thus completing the high-quality assembly and connection of the large-sized skin and the complex frame structure.

[0038] In step one of this embodiment, a special pin structure is added to the frame structure. The shape of the pin is adjusted accordingly according to the shape of the area where it is connected to the frame structure. And there is a pin platform at the bottom of the pin to provide a lock-bottom structure for subsequent welding.

[0039] In step two of this embodiment, precise punching treatment is carried out on the large-sized skinned panel surface. The shape of the holes is the same as the shape of the pins, and the position distribution of the holes corresponds one by one to the distribution of the pins.

[0040] In step three of this embodiment, place the skinned panel surface parallel above the frame. After the pin structure and each corresponding punched hole on the skinned panel surface are matched, lower the skinned panel surface. When the skinned panel surface is evenly in contact with each pin platform, use the penetration welding process on the other side of the skinned panel surface to tightly combine the pin structure and the pin platform with the skinned panel surface.

[0041] In step one of this specific embodiment, after adding pins to the frame, lock-bottom platforms and pin platforms can be formed at the remaining positions of the frame. The platforms provide support for subsequent welding to achieve lock-bottom welding.

[0042] In step one of this specific embodiment, for the pin position distribution, the pin positions cannot coincide with the stress concentration points on the frame structure and avoid relatively complex and changeable positions in the frame structure.

[0043] After the welding process in step three of this specific embodiment is completed, it is necessary to polish the welding surface of the skinned panel surface to make the outer surface of the skinned panel surface smooth without protrusions, thereby avoiding the generation of stress points and corrosion points.

[0044] The beneficial effects of this embodiment are:

[0045] Compared with the existing connection method for large-sized skinned panel surfaces and complex frame structures, through the special pin structure design in this embodiment, while simplifying the process and reducing costs, the connection accuracy is greatly improved, making the frame fit more closely with the outer skin panel surfaces of the wing and the rudder wing, ensuring that the frame will not shift in position due to stress and deformation. The structural integrity of the frame is better preserved, and the task of transmitting stress can be better achieved, enabling the completed rudder wing or wing to withstand greater loads.

[0046] Compared with the existing connection method between the large-sized skin panel surface and the complex skeleton structure, this embodiment changes the screw and nut connection to penetration welding, greatly improving the connection strength, making the panel surface after connection smoother, and at the same time avoiding the problems of connection instability caused by the shedding of screws and nuts due to thermal expansion and long-term corrosion in the environment of alternating high and low temperatures. The structure after connection can be applied to a wider and more demanding service environment.

[0047] This embodiment can achieve the high-precision and high-strength assembly and connection of the large-sized skin panel surface and the complex skeleton structure in the rudder wing and wing. While simplifying the process and reducing costs, it greatly improves the connection accuracy and connection strength of the structure, and further reduces the high-temperature resistance and corrosion resistance of the components after connection, with a wider application.

[0048] In addition to the large-sized skin of the wing surface of aerospace aircraft and the complex support skeleton structure mentioned above, this embodiment is also applicable to other fields, such as seagoing ships or rockets, etc., which involve the high-precision and high-quality assembly and connection of large-sized skin panel surfaces and complex internal skeletons.

[0049] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that in Step 2, the length of the large-sized skin panel surface is set as L, the width is M, and the thickness is H, where 200mm ≤ L, 200mm ≤ M, and 0.5mm ≤ H ≤ 5mm. Others are the same as Specific Embodiment 1.

[0050] Specific Embodiment 3: The difference between this embodiment and either Specific Embodiment 1 or 2 is that in Step 1, the height of the pin structure is set as h, and h = H + 1mm. Others are the same as Specific Embodiment 1 or 2.

[0051] Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that in Step 1, the skeleton structure described is a multi-columnar structure, a multi-row and multi-column frame structure, a truss structure, a truss rib beam structure, a rib or a stiffener structure. Others are the same as Specific Embodiments 1 to 3.

[0052] Specific Embodiment 5: The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that in Step 1, the cross-sectional shape of the pin structure is a square, a circle or a polygonal structure; the distance between the two farthest points of the cross-section of the pin structure is set as D, and D = (0.001 - 0.035)L1, where L1 = min{L, M}. Others are the same as Specific Embodiments 1 to 4.

[0053] Specific Embodiment 6, in combination with Figures 4 to 5Specific description: The difference between this embodiment and any one of the first to fifth specific embodiments is as follows: Let the cross-sectional area of the plug structure in step one be s; when the edge of the contact surface between the plug structure and the plug platform is located within the plug platform, let the area of the end face of the framework in step one be S, then the area M of the plug platform = S - s, and M ≥ 2s; when the end face of the framework where the plug structure is located is divided into multiple plug platforms by the plug structure, let the area of each plug platform be K, and K ≥ s. Others are the same as those in the first to fifth specific embodiments.

[0054] Specific embodiment seven, in combination with Figure 6 Specific description: The difference between this embodiment and any one of the first to sixth specific embodiments is as follows: In step one, the plug structure is processed by integral forming using machining or mechanical assembly connection; the mechanical assembly connection is plug connection or threading. Others are the same as those in the first to sixth specific embodiments.

[0055] Specific embodiment eight: The difference between this embodiment and any one of the first to seventh specific embodiments is as follows: In step one, the position accuracy error of the plug structure ≤ 0.15 mm; in step two, the position accuracy error of the punching ≤ 0.15 mm. Others are the same as those in the first to seventh specific embodiments.

[0056] Specific embodiment nine: The difference between this embodiment and any one of the first to eighth specific embodiments is as follows: In step three, the penetration welding process is used, and the bottom-locking welding method is adopted to closely combine the plug structure with the skin panel on the other side of the skin panel surface; the penetration welding process described in step three is laser welding or electron beam welding. Others are the same as those in the first to eighth specific embodiments.

[0057] Specific embodiment ten: The difference between this embodiment and any one of the first to ninth specific embodiments is as follows: The plug structure and the punching on the skin panel surface in step three are in clearance fit, and the fit tolerance is Tf, and Tf = (0.01 - 0.05)D. Others are the same as those in the first to ninth specific embodiments.

[0058] The following examples are used to verify the beneficial effects of the present invention:

[0059] Example one:

[0060] A method for high-quality assembly and connection integration of a large-size skin and a complex framework structure is carried out according to the following steps:

[0061] I. Manufacturing of the plug of the framework structure:

[0062] A plug structure is processed on the end face of the framework structure in contact with the large-size skin panel surface, and the end face of the framework where the plug structure is located is a plug platform, obtaining a framework structure provided with a plug structure;

[0063] II. Positioning punching of the large-size skin panel surface:

[0064] Perform punching on the large-sized skin panel surface, and then grind the punched holes until smooth to obtain the skin panel surface after punching;

[0065] The punching positions and shapes are consistent with the plug structures;

[0066] III. Assembly and connection of the large-sized skin panel surface and the framework;

[0067] Place one side of the skin panel surface after punching parallel above the framework structure provided with plug structures, so that the punching positions on the skin panel surface correspond to the positions of the plug structures, then insert the plug structures into the punched holes on the skin panel surface, and use the penetration welding process to closely combine the plug structures and the plug platforms with the skin panel surface on the other side of the skin panel surface. Finally, cut off the plug structures that penetrate the skin panel surface and grind them, thus completing the high-quality assembly and connection of the large-sized skin and the complex framework structure.

[0068] In step II, let the length of the large-sized skin panel surface be L, the width be M, and the thickness be H. L = 1000 mm, M = 600 mm, and H = 1 mm.

[0069] Let the height of the plug structure in step I be h, h = H + 1 mm = 2 mm.

[0070] The framework structure described in step I is a truss structure.

[0071] The cross-sectional shape of the plug structure described in step I is rectangular; let the distance between the two farthest points of the cross-section of the plug structure be D, D = 10.2 mm, and the L1 = min{L, M} = 600 mm.

[0072] The end face of the framework where the plug structure is located in step I is divided into 2 plug platforms by the plug structure. Let the cross-sectional area of the plug structure in step I be s, and let the area of each plug platform be K, K = 40 mm 2 , s = 20 mm 2 .

[0073] Specifically, the plug structure is machined integrally by mechanical processing in step I.

[0074] The position accuracy error of the plug structure in step I is 0.1 mm; the position accuracy error of punching in step II is 0.1 mm.

[0075] In step III, use the penetration welding process and adopt the bottom-lock welding method to closely combine the plug structure with the skin panel surface on the other side of the skin panel surface; the penetration welding process described in step III is laser welding.

[0076] The plug structure and the punched hole on the skin panel surface in step III are in clearance fit, and the fit tolerance is Tf, Tf = 0.25 mm.

[0077] Comparative Example 1, the difference between this comparative example and Example 1 is that: Steps 1 and 2 are omitted, and the assembly and connection of the large-size skin panel and the frame structure are directly carried out by laser welding. Others are the same as in Example 1.

[0078] Figure 7 It is a physical diagram of the assembly and connection of the frame structure, the pin structure and the large-size skin panel in Example 1; Figure 8 It is a physical diagram of the skin panel after the high-quality assembly and connection of the large-size skin and the complex frame structure in Example 1; It can be seen from the figure that the panel after connection in Example 1 is smoother, the frame fits closely with the outer skin panel of the rudder wing, there is no deformation or defect, and the strength is higher.

[0079] Figure 9 It is a physical diagram of the connection by ordinary welding in Comparative Example 1; It can be seen from the figure that the parts of the complex frame structure that are preferentially welded will cause the non-welded frame to deform, resulting in problems such as welding failure, frame structure damage and stress concentration during the welding connection of the subsequent welded frame and the skin. The final completed assembly connection is even more difficult to meet the requirements of high-quality and high-precision assembly and connection.

Claims

1. A high-quality integrated assembly and connection method for large-size skin and complex skeleton structure, characterized in that It is carried out in the following steps:

1. Manufacturing of bolts for skeleton structure: A latch structure is machined on the end surface where the skeleton structure contacts the large-size skin panel surface, and the skeleton end surface where the latch structure is located is a latch platform, thereby obtaining a skeleton structure provided with a latch structure; 2. Positioning punching of large-size skin panels: Punching is performed on the large-sized skin panel surface, and then the punched holes are polished to be smooth to obtain the punched skin panel surface; The punching position and shape are consistent with the latch structure; 3. Assembly and connection of large-size skin panels and frames; Place one side of the punched skin panel parallel to the skeleton structure with the latch structure, so that the punching position of the skin panel corresponds to the position of the latch structure, and then insert the latch structure into the punched hole of the skin panel. Use the penetration welding process to tightly combine the latch structure and the latch platform with the skin panel on the other side of the skin panel. Finally, cut off the latch structure that passes through the skin panel and polish it to complete the high-quality assembly and connection of the large-size skin and the complex skeleton structure.

2. A high-quality assembly and connection integration method for a large-size skin and a complex skeleton structure according to claim 1, characterized in that In step 2, the length of the large-size skin panel is L, the width is M, and the thickness is H, 200mm≤L, 200mm≤M, 0.5mm≤H≤5mm.

3. A high-quality assembly and connection integration method for a large-size skin and a complex skeleton structure according to claim 2, characterized in that Assume that the height of the latch structure in step 1 is h, h=H+1mm.

4. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 1 is characterized in that The skeleton structure described in step 1 is a multi-column structure, a multi-row frame structure, a truss structure, a truss-rib beam structure, a rib or a reinforcing rib structure.

5. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 2 is characterized in that The cross-sectional shape of the latch structure described in step 1 is a square, circular or polygonal structure; assuming that the distance between the two farthest points of the cross-sectional area of ​​the latch structure is D, D = (0.001-0.035) L1, and L1 = min{L, M}.

6. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 1 is characterized in that Assume that the cross-sectional area of ​​the latch structure in step one is s; when the edge of the contact surface between the latch structure and the latch platform is located within the latch platform, assume that the area of ​​the end face of the skeleton in step one is S, then the area of ​​the latch platform M=Ss, M≥2s; when the end face of the skeleton where the latch structure is located is divided into multiple latch platforms by the latch structure, assume that the area of ​​each latch platform is K, K≥s.

7. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 1 is characterized in that The pin structure is processed in step 1 by integrally forming the structure through mechanical processing or mechanical assembly connection; the mechanical assembly connection is plug-in or threaded connection.

8. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 1 is characterized in that The position accuracy error of the latch structure in step one is ≤0.15mm; the position accuracy error of the punching hole in step two is ≤0.15mm.

9. The method for high-quality assembly and connection of a large-size skin and a complex skeleton structure according to claim 1 is characterized in that In step three, a penetration welding process is used and a bottom-lock welding method is adopted to tightly combine the latch structure with the skin panel surface on the other side of the skin panel surface; the penetration welding process described in step three is laser welding or electron beam welding.

10. A high-quality assembly and connection integration method of a large-size skin and a complex skeleton structure according to claim 5, characterized in that The latch structure described in step three is clearance-matched with the punched hole on the skin panel surface, and the matching tolerance is Tf, where Tf=(0.01-0.05)D.

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