Spaceflight profile frame flexible multi-point stretch bending die
The flexible multi-point bending mold composed of a base and basic body units achieves the forming of aerospace profile frames with a large central angle of 180° using a purely mechanical structure. This solves the problem that traditional molds cannot form profiles, reduces costs, and improves the shaping accuracy and mold versatility.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SICHUAN AEROSPACE LONG MARCH EQUIP MFG CO LTD
- Filing Date
- 2025-11-14
- Publication Date
- 2026-07-03
AI Technical Summary
Traditional multi-point bending dies cannot directly form aerospace profile frames with a large 180° central angle, and they are costly and rely on complex drive and software systems, making them difficult to promote and apply in aerospace companies.
The flexible multi-point bending die, composed of a base, a first basic unit, and a second basic unit, achieves shape adjustment through a purely mechanical structure. It uses components such as lead screws and cover plates to adjust the envelope surface and combines template positioning pins to achieve precise shape adjustment.
It achieves direct forming of aerospace profile frames with a large 180° central angle, which is low in cost, easy to maintain, has high shaping accuracy, adapts to different profile cross sections, and has strong mold versatility.
Smart Images
Figure CN121514359B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of profile frame forming technology, specifically relating to a flexible multi-point bending die for aerospace profile frame bending forming, suitable for bending processing of aerospace profile frames with a large 180° central angle. Background Technology
[0002] Currently, aerospace products use a large number of profile frame parts. These parts are usually large in size, and the forming processes mainly include stretch bending, roll bending, and pressure bending. Among them, stretch bending has become the preferred forming process for many companies due to its advantages such as low springback and resistance to wrinkling.
[0003] Multi-point bending is a flexible forming process that has been developed in recent years and has been applied in fields such as rail vehicles and architectural decoration. However, aerospace profile frame parts often have a large central angle of about 180°. When using traditional multi-point bending dies, because the shaping method is parallel shaping, the tangents at the theoretical lines at both ends of the part are parallel to the shaping direction. The distance between the contact points between the part and the base body is too large, which easily leads to obvious bending and indentation at both ends. At the same time, the tangents of the envelope lines at both ends of traditional multi-point bending dies do not reach 180°. In addition, the springback of the part and the allowance requirements of the suspension area and clamping area make it impossible for traditional multi-point bending dies to directly bend frame parts with a 180° angle.
[0004] In addition, traditional multi-point bending dies are usually equipped with complex shaping systems and software. The dies are expensive, shape adjustment depends on system support, and they have poor portability, which is not conducive to their promotion and application in aerospace companies.
[0005] Some flexible bending dies use a radial shaping method, which uses a large number of hydraulic cylinders for auxiliary shaping. The hydraulic cylinders are numerous, the structure is complex, and the cost is high. The shaping may also require system and software support. Moreover, the shaping units of this type of die are not arranged compactly and have limited rigidity. When the bending force is at its maximum in the later stage of the bending cycle and the direction is pointing to the back of the die, a few shaping units in the middle of the die that are not parallel to the bending force bear most of the load, affecting the die life and making it difficult to use for long-term bending of large cross-section aerospace profile frames.
[0006] Therefore, there is an urgent need for a multi-point bending die that is simple in structure, reliable in strength, requires no complex driving and software systems, and can achieve flexible bending forming of aerospace profile frames with a large central angle of 180° within a certain forming radius. Summary of the Invention
[0007] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a flexible multi-point bending die for aerospace profile frames. It can meet the bending forming requirements of aerospace profile frames with a large central angle of 180° within a certain forming radius range without the need for complex drive components and shaping systems.
[0008] To achieve the above objectives, the present invention employs the following technical solutions:
[0009] A flexible multi-point bending die for aerospace profile frames includes a base (1), a first basic body unit (2), several sets of second basic body units (3), and template positioning pins (4).
[0010] The base (1) has grooves (12), positioning pin holes (11), and T-shaped grooves (13) on its upper surface. The T-shaped grooves (13) are distributed on both sides of the grooves (12), and each T-shaped groove (13) points to a different center. Each T-shaped groove (13) has a concave T-shaped groove step (14) at the end away from the center.
[0011] The first basic unit (2) includes a first forming block (21) and a first pressing block (22) connected by hexagon socket screws, and the first forming block (21) and the first pressing block (22) are installed inside the groove (12) by hexagon socket screws;
[0012] Each group of second basic body units (3) includes a shaping component (31) and a forming component (32); by rotating the shaping component (31), the corresponding forming component (32) can be driven to move radially along the T-groove (13), thereby adjusting the position of each second basic body unit (3) on the base (1), so that the first basic body unit (2) and several second basic body units (3) together form a mold envelope surface suitable for the bending and forming of aerospace profile frames.
[0013] As a preferred embodiment, the forming component (32) includes a guide block (321). The lower part of the guide block (321) is a T-shaped structure that slides with the T-groove (13), and the upper part is a cylindrical structure. A second forming block (323) is sleeved on the outer side of the cylindrical section of the guide block (321). A second pressure block (324) is connected to the upper end of the second forming block (323) by a screw. A retaining ring (325) is connected to the upper end of the guide block (321) by a screw, and the lower end of the retaining ring (325) can press down on the second forming block (323).
[0014] As a preferred embodiment, the shaping assembly (31) includes a cover plate (312) and a baffle plate (313) that are fixed together on the T-shaped groove step (14) by internal hexagon screws. One end of a lead screw (311) is rotatably provided in the receiving cavity formed between the cover plate (312) and the baffle plate (313). The other end of the lead screw (311) is threadedly connected to the guide block (321) through a trapezoidal thread.
[0015] As a preferred embodiment, the upper surface of the base (1) is also engraved with several theoretical lines (15) of the part arranged along the envelope surface of the aerospace profile frame to be formed. The projection of the theoretical lines (15) of the part on the base (1) is tangent to the projection of the first forming block (21) on the base (1).
[0016] Further preferably, a limiting pin (322) is provided between the guide block (321) and the second forming block (323).
[0017] Further preferably, the working surfaces of the first forming block (21) and the second forming block (323) that contact the aerospace profile frame parts to be formed are both arc surfaces. The radius of the arc surface of the first forming block (21) is smaller than the forming radius of the corresponding part, and the radius of the arc surface of the second forming block (323) is set to be no less than half of the maximum part radius that the mold can form, and no greater than the minimum part radius that the mold can form.
[0018] Further preferably, both the first pressing block (22) and the second pressing block (324) are provided with inclined guide surfaces that face the mold cavity.
[0019] As a preferred embodiment, the number and distribution of the T-slots (13) are matched with the size of the second basic unit (3) and the radius range of the part to be formed.
[0020] As a preferred method, the template positioning pin (4) is inserted into the positioning pin hole (11) for positioning and installing the shaping template during the shaping stage, and is used in conjunction with the theoretical line (15) of the part to make the shaping more accurate.
[0021] Compared with the prior art, the present invention has the following beneficial effects:
[0022] 1. It can directly realize the bending and forming of aerospace profile frames with a large central angle of 180°; by radiating multiple second basic body units and embedded first basic body units along the envelope surface of the part on the base, a continuous multi-point envelope surface is formed together, which overcomes the defects of traditional parallel shaping multi-point bending mold with large contact point spacing at both ends and inability to directly form 180° central angle frame parts.
[0023] 2. The purely mechanical structure enables flexible shaping, resulting in low cost and convenient maintenance. This invention uses a purely mechanical structure such as a lead screw, cover plate, and baffle to adjust the envelope shape, eliminating the need for complex components such as hydraulic cylinders and servo drives, and also avoiding reliance on dedicated software systems. The mold structure is simple, low-cost, and easy to maintain and debug, making it suitable for widespread application in production sites.
[0024] 4. The shaping is intuitive and has good repeatability; the theoretical line of the part engraved on the base is tangent to the projection of the first forming block. The operator can intuitively observe the springback without removing the part and make the shaping based on the in-situ measurement deviation and experience; through the template positioning pin and the shaping template, mechanized shaping can be realized, with good shaping accuracy and repeatability.
[0025] 5. Adaptable to different profile cross sections, with strong mold versatility; by replacing different first basic body units and forming components, it can adapt to the forming requirements of profile frame parts with different cross sections. In the least case, only the second pressure block needs to be replaced to meet the forming requirements of profile frames of different heights. The mold has strong versatility and low modification cost.
[0026] In summary, the flexible multi-point bending die for aerospace profile frames provided by this invention has significant advantages in terms of structural strength, shape adjustment flexibility, forming capability, and cost, and has good engineering application value. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of the overall structure of a flexible multi-point bending mold for aerospace profile frames.
[0028] Figure 2 This is a schematic diagram of the base structure of a flexible multi-point bending mold for aerospace profile frames.
[0029] Figure 3 This is a schematic diagram of the first basic unit structure of a flexible multi-point bending die for aerospace profile frames.
[0030] Figure 4 This is a schematic diagram of the shaping component structure of a flexible multi-point bending mold for aerospace profile frames.
[0031] Figure 5 This is a schematic diagram of the cross-sectional structure of a shaping component for a flexible multi-point bending die for aerospace profile frames.
[0032] Figure 6 This is a schematic diagram of the forming component structure of a flexible multi-point bending die for aerospace profile frames.
[0033] Figure 7 This is a schematic diagram of the cross-sectional structure of a forming component of a flexible multi-point bending die for aerospace profile frames.
[0034] In the figure: 1-base, 2-first basic body unit, 3-second basic body unit, 4-template positioning pin, 11-positioning pin hole, 12-groove, 13-T-slot, 14-T-slot step, 15-part theoretical line, 21-first forming block, 22-first pressure block, 31-shaping component, 32-forming component, 311-lead screw, 312-cover plate, 313-baffle, 321-guide block, 322-limiting pin, 323-second forming block, 324-second pressure block, 325-retaining ring. Detailed Implementation
[0035] The present invention will now be described in detail with reference to the accompanying drawings.
[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0037] Example 1:
[0038] like Figures 1-7 As shown,
[0039] A flexible multi-point bending die for aerospace profile frames is characterized by comprising a base (1), a first basic body unit (2), several sets of second basic body units (3), and template positioning pins (4).
[0040] Among them, the upper surface of the base (1) is provided with groove (12), positioning pin hole (11) and T-shaped groove (13). The T-shaped groove (13) is distributed on both sides of the groove (12), and each T-shaped groove (13) points to a different center. Each T-shaped groove (13) has a concave T-shaped groove step (14) at the end away from the center.
[0041] The first basic unit (2) includes a first forming block (21) and a first pressing block (22) connected by internal hexagon screws, and the first forming block (21) and the first pressing block (22) are installed inside the groove (12) by internal hexagon screws;
[0042] Each group of second basic body units (3) includes a shaping component (31) and a forming component (32); by rotating the shaping component (31), the corresponding forming component (32) can be driven to move radially along the T-groove (13), thereby adjusting the position of each second basic body unit (3) on the base (1), so that the first basic body unit (2) and several second basic body units (3) together form a mold envelope surface suitable for the bending forming of aerospace profile frames.
[0043] The forming component (32) includes a guide block (321). The lower part of the guide block (321) is a T-shaped structure that slides with the T-groove (13), and the upper part is a cylindrical structure, so that the forming component (32) can slide along the T-groove (13) and rotate around the cylindrical axis of the guide block (321). A second forming block (323) is sleeved on the outer side of the cylindrical section on the guide block (321). A second pressure block (324) is connected to the upper end of the second forming block (323) by a screw. A retaining ring (325) is connected to the upper end of the guide block (321) by a screw, and the lower end of the retaining ring (325) can press down on the second forming block (323) to prevent the second forming block (323) and the second pressure block (324) from moving out along the direction of the guide block (321), but leaving a gap for rotation.
[0044] The shaping assembly (31) includes a cover plate (312) and a baffle plate (313) that are fixed together on the T-shaped groove step (14) by internal hexagon screws. One end of a screw rod (311) is rotatably provided in the receiving cavity formed between the cover plate (312) and the baffle plate (313). The other end of the screw rod (311) is threadedly connected to the guide block (321). By rotating the screw rod (311), the corresponding forming assembly (32) can be driven to move radially along the T-shaped groove (13), thereby achieving the purpose of adjusting the position of each second basic body unit (3) on the base (1).
[0045] The upper surface of the base (1) is also engraved with several theoretical lines (15) of the part arranged along the envelope surface of the aerospace profile to be formed. The projection of the theoretical line (15) of the part on the base (1) is tangent to the projection of the first forming block (21) on the base (1), which is used to observe the springback of the part during the bending process and as a reference for shaping.
[0046] A limiting pin (322) is provided between the guide block (321) and the second forming block (323). The limiting pin (322) is used to restrict the second forming block (323) and the second pressing block (324) so that one side of its forming arc surface always faces the part to be formed.
[0047] The working surfaces of the first forming block (21) and the second forming block (323) that contact the aerospace profile frame parts to be formed are both arc surfaces. The radius of the arc surface of the first forming block (21) is smaller than the forming radius of the corresponding part. The radius of the arc surface of the second forming block (323) is set to be no less than half of the radius of the largest part that the mold can form, and no greater than the radius of the smallest part that the mold can form, so that different radii of mold envelope surfaces can be formed by adjusting the position combination of each second basic body unit (3).
[0048] Both the first pressure block (22) and the second pressure block (324) are provided with inclined guide surfaces facing the mold cavity, which are used to guide the parts into the mold cavity and limit the deformation of the parts in the height direction when warping occurs after bending and heat treatment; wherein, the bottom surface of the second pressure block (324) is higher than the height of the profile used in the aerospace profile frame to be formed, so as to avoid scratching the surface of the parts during bending and clamping.
[0049] The number and distribution of T-slots (13) are matched with the size of the second basic unit (3) and the radius range of the part to be formed. Under the premise of ensuring that each second basic unit (3) does not interfere with each other during the shaping process, the extension direction of each T-slot (13) is arranged as close as possible to the center of the mold envelope surface so as to form a multi-point forming unit with radial distribution.
[0050] The template positioning pin (4) is inserted into the positioning pin hole (11) and is used to position and install the adjustment template during the adjustment stage. It is used in conjunction with the theoretical line (15) of the part. After the adjustment is completed, the template positioning pin (4) and the adjustment template can be removed. The mold envelope surface formed by the adjustment is retained for the bending and forming of the 180° large central angle aerospace profile frame, making the adjustment more accurate.
[0051] Shaping and usage instructions:
[0052] During shaping, the template positioning pin 4 is inserted into the positioning pin hole 11 of the base 1 to install the shaping template, which serves as the mechanical shaping reference. According to the shaping template and the theoretical line 15 of the part, the operator rotates the lead screw 311 one by one on the bending machine, driving each forming component 32 to move along the T-slot 13, so that the forming arc surface of the second forming block 323 and the second pressure block 324 fits against the shaping template, realizing the precise shaping of the envelope surface. After shaping, the template positioning pin 4 and the shaping template are removed, and the aerospace profile frame to be formed is placed in the mold envelope cavity. The profile is then bent and shaped using the bending machine.
[0053] Through the above structure and method, the present invention can achieve flexible multi-point stretch bending forming of aerospace profile frames through a purely mechanical structure without the need for complex drive mechanisms and software systems such as hydraulic cylinders and servo systems. It can meet the stretch bending requirements of aerospace profile frames with a large central angle of 180° within a certain forming radius range. The mold has low cost, reliable strength, and convenient shaping operation.
[0054] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.
Claims
1. A flexible multi-point stretch-draw die for aerospace profile frames, characterized by: It includes a base (1), a first basic body unit (2), several sets of second basic body units (3) and template positioning pins (4); The base (1) has grooves (12), positioning pin holes (11), and T-shaped grooves (13) on its upper surface. The T-shaped grooves (13) are distributed on both sides of the grooves (12), and each T-shaped groove (13) points to a different center. Each T-shaped groove (13) has a concave T-shaped groove step (14) at the end away from the center. The first basic unit (2) includes a first forming block (21) and a first pressing block (22) connected by hexagon socket screws, and the first forming block (21) and the first pressing block (22) are installed inside the groove (12) by hexagon socket screws; Each group of second basic body units (3) includes a shaping component (31) and a forming component (32); by rotating the shaping component (31), the corresponding forming component (32) can be driven to move radially along the T-groove (13), thereby adjusting the position of each second basic body unit (3) on the base (1), so that the first basic body unit (2) and several second basic body units (3) together form a mold envelope surface suitable for the bending forming of aerospace profile frames; The forming component (32) includes a guide block (321). The lower part of the guide block (321) is a T-shaped structure that slides with the T-groove (13), and the upper part is a cylindrical structure. A second forming block (323) is sleeved on the outer side of the cylindrical section of the guide block (321). A second pressure block (324) is connected to the upper end of the second forming block (323) by a screw. A retaining ring (325) is connected to the upper end of the guide block (321) by a screw, and the lower end of the retaining ring (325) can press down on the second forming block (323). The working surfaces of the first forming block (21) and the second forming block (323) that contact the aerospace profile frame parts to be formed are both arc surfaces. The radius of the arc surface of the first forming block (21) is smaller than the forming radius of the corresponding part, and the radius of the arc surface of the second forming block (323) is set to be no less than half of the maximum part radius that the mold can form, and no greater than the minimum part radius that the mold can form.
2. A flexible multi-point stretch-draw die for aerospace profile frames according to claim 1, characterized in that: The shaping assembly (31) includes a cover plate (312) and a baffle plate (313) that are fixed together on the T-shaped groove step (14) by internal hexagon screws. One end of a lead screw (311) is rotatably provided in the receiving cavity formed between the cover plate (312) and the baffle plate (313). The other end of the lead screw (311) is threadedly connected to the guide block (321) through a trapezoidal thread.
3. A flexible multi-point stretch-draw die for aerospace profile frames according to claim 1, characterized in that: The upper surface of the base (1) is also engraved with several theoretical lines (15) of the part arranged along the envelope surface of the aerospace profile frame to be formed. The projection of the theoretical lines (15) of the part on the base (1) is tangent to the projection of the first forming block (21) on the base (1).
4. The flexible multi-point bending die for aerospace profile frames according to claim 1, characterized in that: A limiting pin (322) is provided between the guide block (321) and the second forming block (323).
5. The flexible multi-point bending die for aerospace profile frames according to claim 1, characterized in that: Both the first pressing block (22) and the second pressing block (324) are provided with inclined guide surfaces that face the mold cavity.
6. The flexible multi-point bending die for aerospace profile frames according to claim 1, characterized in that: The number and distribution of the T-slots (13) are matched with the size of the second basic unit (3) and the radius range of the part to be formed.
7. The flexible multi-point bending die for aerospace profile frames according to claim 3, characterized in that: The template positioning pin (4) is inserted into the positioning pin hole (11) and is used to position and install the shaping template during the shaping stage. It is used in conjunction with the theoretical line (15) of the part to make the shaping more accurate.