Robot mirror image forming device and method with local constraint mechanism

Abstract

The invention provides a robot mirror image forming device and method with a local constraint mechanism, and belongs to the technical field of metal component forming and manufacturing. The device comprises a mirror image forming machining system, a blank fixing tool system, a movable constraint block blank pressing system and a device cooperative motion control system, wherein the mirror image forming machining system controls a forming loading tool to work through a six-degree-of-freedom mechanical arm; the blank fixing tool system stabilizes the metal plate blank; the movable constraint block blank pressing system realizes multidirectional movement of a constraint block and heats a metal plate blank by virtue of a motor, a guide rail and the like; the device cooperative motion control system guarantees cooperative operation of all parts. The method comprises the steps of blank solution treatment, tool positioning and blank heating, blank hot forming and preformed part aging treatment, and finally the metal forming component is obtained. The method solves the problems of low precision, easy collapse and cracking, high production cost and uncontrollable structure performance during thin-wall metal plate complex local small feature forming in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of metal component forming and manufacturing, and in particular to a robot mirror forming device and method with a local constraint mechanism. Background Art

[0002] In the field of metal component forming and manufacturing, especially in the manufacturing of high-end aerospace equipment, the demand for high-strength aluminum alloy thin-walled components is growing. Such components are key components for achieving lightweight aerospace equipment and improving structural stiffness. Take the bomb bay door of the fourth-generation aircraft as an example. When it is opened for bombing at supersonic cruise, it needs to withstand extremely high aerodynamic loads, which requires thin-walled components to have extremely high structural stiffness. For this reason, 7xxx series high-strength aluminum alloys are often used for manufacturing. However, components made of this material have the characteristics of a wall thickness of only 2mm, complex structure and complex small features, small fillet ratio (ratio of radius to fillet r / t≤5), and protrusion height-to-thickness ratio (ratio of height to thickness H / t≥15). The coupling of structure and material makes forming extremely difficult.

[0003] At present, traditional forming methods have many difficulties in dealing with such complex thin-walled components. Paired steel die forming, as the first generation of thin-walled component forming technology, forms metal sheets through two concave and convex molds, and is used to manufacture large-sized aluminum alloy lightweight thin-walled components. However, this method has poor adaptability to the material properties of 7xxx series high-strength aluminum alloys. The material has limited plastic deformation capacity at room temperature and low elongation during cold forming. When the component has a small radius of curvature or local convex features, the material flow is hindered, and stress concentration is easily generated, resulting in micro cracks or even macro cracks. In addition, subsequent heat treatment is required after semi-hard forming to achieve the T6 state strength target. However, the residual stress generated by uneven mold constraints during the forming process and the heat treatment phase change stress are superimposed, which will lead to shape distortion. For asymmetric thin-walled structures, warping deformation is difficult to eliminate through correction processes, which seriously affects assembly accuracy. In addition, steel mold forming relies on fixed cavity matching, cannot adjust local pressure distribution in real time, lacks adaptive compensation mechanism, easily causes uneven wall thickness or surface wrinkles, and is difficult to accurately control organizational properties and dimensional accuracy, which cannot meet the needs of high-end equipment for high reliability and integrated development of components.

[0004] Single-mold high-pressure forming technology belongs to the second-generation forming technology. It needs to apply extremely high hydraulic loads during the forming process, especially in the area of ​​local fine features of the component (such as the ratio of local feature radius to wall thickness r / t≤3). In order to ensure that the material completely fills the mold, large-scale hydraulic equipment with a capacity of 10,000 tons is often required. This not only leads to huge equipment investment and significantly increases energy consumption in the production process, but also causes stress concentration in the mold and the material, causing uneven local plastic deformation, which may lead to defects such as microcracks and large residual stress in the forming area, reducing the overall performance and service life of the parts. At the same time, the temperature rises rapidly during hydraulic forming, and the friction and thermal effects generated under high loads will also have an adverse effect on the material properties, increasing the risk of thermal deformation of parts and mold wear.

[0005] The mirror forming technology uses a rigid single point and a mirror elastic mold to load in coordination. With the help of the robot trajectory, it can form complex component shapes, form a three-dimensional stress field at the local contact point, and use the normal stress to cross the necking bottleneck of the two-dimensional stress deformation, significantly improving the forming force. This technology does not require the design and manufacture of molds, which can reduce the cost of the forming process, and can adjust the process parameters in real time during the forming process to ensure the precise forming of complex local small features of thin-walled components. However, during the forming process of overall large-sized reinforced thin-walled components, the sheet material around the local feature forming will collapse, resulting in a large deviation from the expected forming accuracy of the overall component; in addition, it is more difficult to perform hot forming after the overall heat treatment of large-area slabs, and the dimensional accuracy of the final formed component is poor.

[0006] In summary, existing forming methods generally have problems such as low production efficiency, low forming accuracy and weak component performance, and they cannot meet the forming requirements of thin-walled complex components in the aerospace field. Summary of the invention

[0007] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a robot mirror forming device and method with a local constraint mechanism, which solves the problems of low precision, easy collapse and cracking, high production cost and uncontrollable organizational properties in the prior art when forming complex local small features of thin-walled metal sheets, and realizes high-precision, high-performance and low-cost integrated forming of thin-walled metal sheets with controlled shape and properties.

[0008] To achieve the above object, the present invention provides the following solutions: A robot mirror forming device with a local constraint mechanism comprises a mirror forming processing system, a blank fixing tooling system, a mobile constraint block edge holding system and a device coordinated motion control system; the blank fixing tooling systems are respectively arranged at both ends of a metal sheet blank, and the mirror forming processing system is located on both sides of the blank fixing tooling system, and is used for mirror forming processing of the metal sheet blank fixed on the blank fixing tooling system; the mobile constraint block edge holding system is arranged around the corresponding blank fixing tooling system, and is used for applying local constraints to the edge of the metal sheet blank to prevent the metal sheet blank from displacement and deformation during processing; the device coordinated motion control system is respectively connected to the mirror forming processing system, the blank fixing tooling system and the mobile constraint block edge holding system, and is used for controlling the coordinated work of each system to ensure efficient and stable operation of the entire device.

[0009] Preferably, the two groups of the mirror image forming processing systems include a six-degree-of-freedom robotic arm, a forming loading tool, a camera and a support block; the two six-degree-of-freedom robotic arms are symmetrically arranged, and the two forming loading tools are respectively connected to the ends of the corresponding six-degree-of-freedom robotic arms, and the six-degree-of-freedom robotic arms control the rotation of the forming loading tools through a motor to realize the forming of the metal sheet blank; the two cameras are respectively connected to one side of the corresponding six-degree-of-freedom robotic arm close to the forming loading tool for real-time monitoring of the processing status; the two support blocks and the forming loading tool are respectively fixedly connected to the corresponding six-degree-of-freedom robotic arm through a three-jaw chuck; the forming loading tool contacts the metal sheet blank by rotating, and the six-degree-of-freedom robotic arm provides feed in the X-axis, Y-axis and Z-axis directions to the corresponding forming loading tool, and the six-degree-of-freedom robotic arm on the other side drives the corresponding support block to follow the movement; an infrared thermometer is installed on the punch of the mirror image forming processing system, and the infrared thermometer is connected to the device collaborative motion control system.

[0010] Preferably, the blank fixing tooling system is composed of two groups of fixing mechanisms, and both groups of the fixing mechanisms include a base and a clamp; the clamp is connected to the base, and is used to fix the metal sheet blank to ensure that the metal sheet blank maintains a stable position and posture during the processing; the base provides support for the entire blank fixing tooling system to ensure the overall stability of the device; the clamping surface width of the clamp is 5-10cm to accommodate metal sheet blanks of different sizes.

[0011] Preferably, the movable constraint block pressing system includes a horizontal cylinder, a heat insulation plate, a constraint block, a resistance heating rod, a mobile platform, a slider, a wire cylinder, a coupling, a motor, a motor fixing plate, a guide rail and a horizontal cylinder fixing plate; the guide rail is connected to the base, the slider slides with the guide rail, and the slider is connected to the mobile platform to provide a mobile foundation for the device components; the horizontal cylinder is bolted to the mobile platform to provide the constraint block with movement along the Z-axis direction, and a horizontal cylinder fixing plate is installed on the horizontal cylinder, and the horizontal cylinder fixing plate is connected to another horizontal cylinder by bolts to provide the constraint block with movement along the Y-axis direction; the heat insulation plate is connected to the horizontal cylinder Between the constraint block, it is used to isolate the heat generated by the constraint block to prevent the heat from being transferred to the horizontal cylinder and affecting its performance; the constraint block is connected to the output end of the horizontal cylinder, directly acts on the edge of the metal sheet blank, and applies constraint pressure; the resistance heating rod is connected to the constraint block, and the sheet to be formed is heated through the constraint block; the motor is connected to the motor fixing plate, and the motor fixing plate is connected to the base through bolts, and the output shaft of the motor is connected to the wire cylinder through a coupling, and the wire cylinder cooperates with the slider, and when the motor rotates, it drives the wire cylinder to rotate, thereby driving the slider and the moving platform to move along the guide rail; the power of the resistance heating rod is 1-2kW.

[0012] Preferably, the collaborative motion control system of the device includes a central controller, a control console and cables; the central controller is connected to the mirror forming processing system, the mobile constraint block pressing system and the blank fixing tooling system through cables, and is used to receive feedback information from each system, and issue control instructions according to a preset program to coordinate the actions of each system. The cable adopts a shielded cable to reduce signal interference; the control console is connected to one side of the central controller, and is used for the operator to input control instructions and set processing parameters and motion trajectory.

[0013] The present invention also provides a forming method using the above-mentioned robot mirror forming device with a local constraint mechanism, comprising the following steps: S1. Solution treatment of the metal sheet blank is performed in a heating furnace and the blank is kept warm to obtain a uniform microstructure with good plasticity, and then the blank is transferred to clean water at room temperature and cooled to room temperature; S2, fixing the cooled metal sheet blank to the blank fixing fixture system, moving the constraint block to be close to the blank by moving the constraint block edge holding system, and heating the metal sheet blank to the target temperature by using the resistance heating rod in the constraint block; S3. After the metal sheet blank is heated to the target temperature, the mobile platform drives the constraint blocks to move to both sides of the heating area, and the horizontal cylinder pushes the constraint blocks to press the blank and apply the blank holding force; then the robot trajectory is planned through the device collaborative motion control system, and the forming loading tool of the mirror forming processing system is controlled to perform hot forming on the heating area to form complex local small features; S4, repeat S3 until all the complex small features are formed, then cool the preform to room temperature, unload the blank holding force, take out the preform for aging treatment, and finally cut off the excess to finally obtain a metal formed component.

[0014] Preferably, in S1, the temperature of the solution treatment of the metal sheet blank is 450-500°C, the solution time is not less than 30 minutes, the insulation time of the metal sheet blank after the solution treatment is 20-40 minutes, and the transfer time of transferring the metal sheet blank after the solution treatment into clean water through a transfer tool is 3-10 seconds.

[0015] Preferably, in S2, the target temperature is 20-500°C.

[0016] Preferably, in S3, the horizontal cylinder pushes the constraint block to press the blank, the applied blank holding force is 0-5t, the rotation speed of the forming loading tool is 0-1000rpm, the punch feed rate of the mirror forming processing system is 1000-2000mm / min, and the applied forming force is 0-5000N.

[0017] Preferably, in S4, the aging treatment process of the preform is: putting the taken out preform into an aging furnace at a temperature of 100-200° C. for insulation for a time of 6-36 hours.

[0018] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: (1) The present invention utilizes a collaborative system composed of a mobile platform and a constraint block to apply a dynamically adjustable blank holding force around the area to be formed, thereby effectively avoiding the collapse of the sheet metal during the mirror progressive forming process and reducing the impact on the surrounding sheets; local heating treatment significantly reduces the material springback rate, thereby significantly improving the forming accuracy.

[0019] (2) In the sheet forming process provided by the present invention, the temperature, rotation speed, feed rate and forming force can all be controlled. By optimizing the process parameters, a thin-walled part with uniform wall thickness can be obtained. The rigid single point and mirror elastic mold are used for coordinated loading to form a three-dimensional stress field locally in the blank, thereby improving the forming limit and avoiding cracking defects during the forming of local bulges. In addition, the heating operation further improves the formability of the sheet.

[0020] (3) The technical solution provided by the present invention adopts a moldless forming process, eliminating the mold processing link, avoiding the structural limitations of traditional mold forming, and can process complex geometric shapes such as free-form surfaces and thin-walled blades; at the same time, it reduces energy consumption and carbon emissions, complies with the principles of sustainable development, effectively reduces production costs and production cycles, and has strong processing flexibility.

[0021] (4) The present invention can obtain good phase distribution and grain size and improve the forming performance by controlling the forming temperature and heating rate of the sheet metal; the temperature at different positions can be controlled in different zones, and a gradient structure can be obtained according to the performance requirements of different deformation zones of the metal thin-walled components, so that the metal thin-walled components have both high formability and customized performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 A schematic diagram of the overall structure in the XOY direction provided for a robot mirror image forming device with a local constraint mechanism of the present invention; Figure 2 A schematic diagram of the structure in the XOZ direction provided for a robot mirror image forming device with a local constraint mechanism of the present invention; Figure 3 A schematic diagram of the structure of a restraining block and a resistance heating rod projected in the horizontal direction for a robot mirror image forming device with a local restraining mechanism according to the present invention; Figure 4 It is a flow chart of a forming method of a robot mirror forming device with a local constraint mechanism of the present invention; Figure 5 This is a schematic diagram of the structure of the formed part provided by the present invention.

[0024] Description of reference numerals: 1. Mirror forming processing system; 11. Six-degree-of-freedom robotic arm; 12. Forming loading tool; 13. Camera; 14. Support block; 2. Blank fixing tooling system; 21. Base; 22. Fixture; 3. Mobile constraint block pressing system; 31. Horizontal cylinder; 32. Heat insulation board; 33. Constraint block; 34. Resistance heating rod; 35. Mobile platform; 36. Slider; 37. Screw cylinder; 38. Coupling; 39. Motor; 310. Motor fixing plate; 311. Guide rail; 312. Horizontal cylinder fixing plate; 4. Device coordinated motion control system; 41. Central controller; 42. Control console; 43. Cable; 5. Metal sheet blank. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Example 1 like Figure 1 and Figure 2 As shown, the present invention provides a robot mirror forming device with a local constraint mechanism, including a mirror forming processing system 1, a blank fixing tooling system 2, a mobile constraint block edge holding system 3 and a device collaborative motion control system 4; the blank fixing tooling system 2 is respectively arranged at both ends of a metal sheet blank 5, and the mirror forming processing system 1 is located on both sides of the blank fixing tooling system 2, and is used for mirror forming processing of the metal sheet blank 5 fixed on the blank fixing tooling system 2; the mobile constraint block edge holding system 3 is arranged around the corresponding blank fixing tooling system 2, and is used for applying local constraints to the edge of the metal sheet blank 5 to prevent the metal sheet blank 5 from displacement and deformation during the processing; the device collaborative motion control system 4 is respectively connected to the mirror forming processing system 1, the blank fixing tooling system 2, and the mobile constraint block edge holding system 3, and is used for controlling the collaborative work of each system to ensure efficient and stable operation of the entire device.

[0028] According to the above content, the two sets of mirror image forming processing systems 1 include a six-degree-of-freedom robot arm 11, a forming loading tool 12, a camera 13 and a support block 14; the two six-degree-of-freedom robot arms 11 are symmetrically arranged, and the two forming loading tools 12 are respectively connected to the ends of the corresponding six-degree-of-freedom robot arms 11. The six-degree-of-freedom robot arms 11 control the rotation of the forming loading tools 12 through the motor 39 to realize the forming of the metal sheet blank 5; the two cameras 13 are respectively connected to one side of the corresponding six-degree-of-freedom robot arm 11 close to the forming loading tool 12 for real-time monitoring. Processing conditions; the two support blocks 14 and the forming loading tool 12 are fixedly connected to the corresponding six-degree-of-freedom mechanical arm 11 through a three-jaw chuck respectively; the forming loading tool 12 contacts the metal sheet blank 5 by rotating, and the six-degree-of-freedom mechanical arm 11 provides feeding in the X-axis, Y-axis and Z-axis directions to the corresponding forming loading tool 12, and the six-degree-of-freedom mechanical arm 11 on the other side drives the corresponding support block 14 to follow the movement; an infrared thermometer is installed on the punch of the mirror forming processing system 1, and the infrared thermometer is connected to the device cooperative motion control system 4. When hot forming, the materials of the forming loading tool 12 and the back support block 14 can be selected from commonly used mold materials for hot forming, such as low carbon steel, stainless steel, Ni7N, etc., and asbestos is wrapped on the outside to reduce convection and radiation heat exchange between the mold and the external environment during the heat transfer process and improve the uniformity of the mold temperature; when the forming temperature is room temperature, the back support block 14 of the forming loading tool 12 can be made of polyurethane elastomer. In addition, the forming loading tool 12 can be a ball-head-shaped tool, the size of which is selected according to the specific processing characteristics, and the contact area geometry of the forming recording tool is a spherical tool tip, which is round.

[0029] The blank fixing fixture system 2 is composed of two sets of fixing mechanisms, both of which include a base 21 and a clamp 22; the clamp 22 is connected to the base 21, and is used to fix the metal sheet blank 5 to ensure that the metal sheet blank 5 maintains a stable position and posture during the processing; the base 21 provides support for the entire blank fixing fixture system 2 to ensure the overall stability of the device; the clamping surface width of the clamp 22 is 5-10cm to accommodate metal sheet blanks 5 of different sizes.

[0030] The movable restraining block edge pressing system 3 includes a horizontal cylinder 31, a heat insulation plate 32, a restraining block 33, a resistance heating rod 34, a movable platform 35, a slider 36, a wire cylinder 37, a coupling 38, a motor 39, a motor fixing plate 310, a guide rail 311 and a horizontal cylinder fixing plate 312; the guide rail 311 is connected to the base 21, the slider 36 is slidably matched with the guide rail 311, and the slider 36 is connected to the movable platform 35 to provide a movable foundation for the device components; the horizontal cylinder 31 is bolted to the movable platform 35 to provide The constraint block 33 moves along the Z-axis direction. A horizontal cylinder fixing plate 312 is installed on the horizontal cylinder 31. The horizontal cylinder fixing plate 312 is connected to another horizontal cylinder 31 by bolts to provide the constraint block 33 with movement along the Y-axis direction. The heat insulation plate 32 is connected between the horizontal cylinder 31 and the constraint block 33 to isolate the heat generated by the constraint block 33 and prevent the heat from being transferred to the horizontal cylinder 31 and affecting its performance. The constraint block 33 is connected to the output end of the horizontal cylinder 31 and directly acts on the edge of the metal sheet blank 5 to apply constraint pressure. Figure 3 The resistance heating rod 34 is connected to the constraint block 33, and the sheet to be formed is heated through the constraint block 33; the motor 39 is connected to the motor fixing plate 310, and the motor fixing plate 310 is connected to the base 21 through bolts. The output shaft of the motor 39 is connected to the wire cylinder 37 through the coupling 38, and the wire cylinder 37 cooperates with the slider 36. When the motor 39 rotates, it drives the wire cylinder 37 to rotate, thereby driving the slider 36 and the moving platform 35 to move along the guide rail 311; the power of the resistance heating rod 34 is 1-2kW.

[0031] In the above structure, the horizontal cylinder 31 is a servo telescopic cylinder, including but not limited to an electric telescopic cylinder and a pneumatic telescopic cylinder, to ensure the accurate stroke of the constraint block 33. And the material of the constraint block 33 is selected from the commonly used mold materials for hot forming, such as low carbon steel, stainless steel, Ni7N, etc., to ensure that a suitable blank holding force is provided. The material of the heat insulation board 32 is selected from asbestos board, fireproof board and other materials to prevent heat from being transferred to the horizontal cylinder 31 and the device to avoid damage to the device. The motor 39 is selected from a servo motor or an oil cylinder to ensure the movement of the constraint block 33.

[0032] The device collaborative motion control system 4 includes a central controller 41, a control console 42 and a cable 43; the central controller 41 is connected to the mirror forming processing system 1, the mobile constraint block edge holding system 3, and the blank fixing tooling system 2 through the cable 43, and is used to receive feedback information from each system, and issue control instructions according to a preset program to coordinate the actions of each system. The cable 43 uses a shielded cable to reduce signal interference; the control console 42 is connected to one side of the central controller 41, and is used for the operator to input control instructions and set processing parameters and motion trajectories.

[0033] Example 2 Reference Figure 4This embodiment provides a forming method using the robot mirror forming device with a local constraint mechanism described in Embodiment 1, comprising the following steps: S1. Solution treatment of the metal sheet blank is performed in a heating furnace and the blank is kept warm to obtain a uniform microstructure with good plasticity, and then the blank is transferred to clean water at room temperature and cooled to room temperature; S2, fixing the cooled metal sheet blank to the blank fixing fixture system, moving the constraint block to be close to the blank by moving the constraint block edge holding system, and heating the metal sheet blank to the target temperature by using the resistance heating rod in the constraint block; S3. After the metal sheet blank is heated to the target temperature, the mobile platform drives the constraint blocks to move to both sides of the heating area, and the horizontal cylinder pushes the constraint blocks to press the blank and apply the blank holding force; then the robot trajectory is planned through the device collaborative motion control system, and the forming loading tool of the mirror forming processing system is controlled to perform hot forming on the heating area to form complex local small features; S4, repeat S3 until all the complex small features are formed, then cool the preform to room temperature, unload the blank holding force, take out the preform for aging treatment, and finally cut off the excess to finally obtain a metal formed component.

[0034] Among them, in S1, the temperature of the metal sheet blank for solution treatment is 450-500℃, the solution time is not less than 30min, the insulation time of the metal sheet blank after solution treatment is 20-40min, and the transfer time of the metal sheet blank after solution treatment to clean water through the transfer tool is 3-10s, the purpose is to make the alloy elements evenly distributed in the metal matrix, the metal sheet blank here can be selected from 7xxx series aluminum alloy, and the temperature is in the optimal range to avoid excessive temperature and overburning of the structure. In S2, the target temperature is 20-500℃. In S3, the horizontal cylinder pushes the constraint block to press the blank, and the applied clamping force is 0-5t, which can effectively prevent local collapse during the mirror progressive forming process and avoid affecting the forming progress. The rotation speed of the forming loading tool is 0-1000rpm, the punch feed rate of the mirror forming processing system is 1000-2000mm / min, and the applied forming force is 0-5000N. In S4, the aging treatment process of the preform is as follows: the taken-out preform is placed in an aging furnace at a temperature of 100-200° C. for insulation for a period of 6-36 hours.

[0035] Example 3 In this embodiment, taking high-strength aluminum alloy 7075 with a wall thickness of 2 mm as an example, the device provided in Example 1 and the forming method of Example 2 are used for further verification, which specifically includes the following steps: Step 1: Perform solid solution treatment on high-strength aluminum alloy 7075 in a high-temperature heating furnace; first, increase the temperature of the ambient heating furnace to 457°C, and the solid solution time is 30 minutes. Then, after the solid solution treatment, keep the furnace warm for 30 minutes to make the alloy elements evenly distributed in the aluminum matrix; finally, after the insulation is completed, quickly transfer the billet to clean water for cooling through a transfer tool, and the cooling time is not less than 5 minutes.

[0036] Step 2: Install the solution treated blank into the device frame provided in Example 1, use the mobile platform to drive the constraint block to clamp the blank, and heat the high-strength aluminum alloy 7075 blank to 450°C.

[0037] Step 3. After the high-strength aluminum alloy 7075 billet is heated to 450°C, the mobile platform drives the constraint block to move to the heating area, and the horizontal cylinder pushes the constraint block to press the billet, providing a clamping force of 0-5t, thereby preventing local collapse during the forming process and avoiding affecting the forming accuracy; then the robot trajectory is planned through the device collaborative motion control system, and the forming loading tool of the mirror forming processing system is controlled to move along the billet surface for forming. During the forming process, the rotation speed of the forming loading tool is 250rpm, the punch feed rate is 1000mm / min, and the forming force range that the mirror forming processing systems on both sides can provide is 0-5000N.

[0038] Step 4: Repeat step 3 until all the complex small features are formed, then unload the blank holder force, remove the device, take out the preformed component and put it into the aging furnace for aging treatment. The aging temperature of high-strength aluminum alloy 7075 is 120°C and the aging time is 18h. Cut the forming area and cut the allowance to complete the forming and manufacturing of large-size aluminum alloy lightweight thin-walled components.

[0039] Reference Figure 5 As shown, the four parts formed by the above method and device can be inferred to have similar frame contour shapes, which further illustrates that the robot mirror forming device with a local constraint mechanism is capable of processing such components with complex shapes, and reflects the ability of the device to process a variety of shapes in thin-walled metal sheet forming, demonstrating its feasibility and versatility in manufacturing parts with similar structural features in actual production.

[0040] Therefore, the above-mentioned robot mirror forming device and method with a local constraint mechanism is adopted to solve the problems of low precision, easy collapse and cracking, high production cost and uncontrollable organizational properties in the prior art when forming complex local small features of thin-walled metal sheets, and realizes high-precision, high-performance and low-cost integrated forming of thin-walled metal sheets with controlled shape and properties.

[0041] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0042] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A robot mirror image forming device with a local constraint mechanism, characterized in that: It includes a mirror forming processing system, a blank fixing tooling system, a mobile constraint block edge holding system and a device coordinated motion control system; the blank fixing tooling system is respectively arranged at both ends of the metal sheet blank, and the mirror forming processing system is located on both sides of the blank fixing tooling system, and is used for mirror forming processing of the metal sheet blank fixed on the blank fixing tooling system; the mobile constraint block edge holding system is arranged around the corresponding blank fixing tooling system, and is used for applying local constraints to the edge of the metal sheet blank to prevent the metal sheet blank from displacement and deformation during the processing; the device coordinated motion control system is respectively connected to the mirror forming processing system, the blank fixing tooling system and the mobile constraint block edge holding system, and is used for controlling the coordinated work of each system to ensure efficient and stable operation of the entire device.

2. A robot mirror image forming device with a local constraint mechanism according to claim 1, characterized in that: The two groups of mirror image forming processing systems include a six-degree-of-freedom robotic arm, a forming loading tool, a camera and a support block; the two six-degree-of-freedom robotic arms are symmetrically arranged, and the two forming loading tools are respectively connected to the ends of the corresponding six-degree-of-freedom robotic arms. The six-degree-of-freedom robotic arms control the rotation of the forming loading tools through a motor to realize the forming of the metal sheet blank; the two cameras are respectively connected to one side of the corresponding six-degree-of-freedom robotic arm close to the forming loading tool for real-time monitoring of the processing status; the two support blocks and the forming loading tool are respectively fixedly connected to the corresponding six-degree-of-freedom robotic arm through a three-jaw chuck; the forming loading tool contacts the metal sheet blank through rotation, and the six-degree-of-freedom robotic arm provides feeding in the X-axis, Y-axis and Z-axis directions to the corresponding forming loading tool, and the six-degree-of-freedom robotic arm on the other side drives the corresponding support block to follow the movement; an infrared thermometer is installed on the punch of the mirror image forming processing system, and the infrared thermometer is connected to the device collaborative motion control system.

3. A robot mirror image forming device with a local constraint mechanism according to claim 1, characterized in that: The blank fixing tooling system is composed of two groups of fixing mechanisms, and both groups of the fixing mechanisms include a base and a clamp; the clamp is connected to the base and is used to fix the metal sheet blank to ensure that the metal sheet blank maintains a stable position and posture during the processing; the base provides support for the entire blank fixing tooling system to ensure the overall stability of the device; the clamping surface width of the clamp is 5-10cm to accommodate metal sheet blanks of different sizes.

4. The robot mirror image forming device with a local constraint mechanism according to claim 1, characterized in that: The movable constraint block edge pressing system includes a horizontal cylinder, a heat insulation plate, a constraint block, a resistance heating rod, a mobile platform, a slider, a wire cylinder, a coupling, a motor, a motor fixing plate, a guide rail and a horizontal cylinder fixing plate; the guide rail is connected to the base, the slider slides with the guide rail, and the slider is connected to the mobile platform to provide a mobile foundation for the device components; the horizontal cylinder is bolted to the mobile platform to provide the constraint block with movement along the Z axis, and a horizontal cylinder fixing plate is installed on the horizontal cylinder, and the horizontal cylinder fixing plate is connected to another horizontal cylinder by bolts to provide the constraint block with movement along the Y axis; the heat insulation plate is connected to the horizontal cylinder and about The bundle blocks are used to isolate the heat generated by the constraint block to prevent the heat from being transferred to the horizontal cylinder and affecting its performance; the constraint block is connected to the output end of the horizontal cylinder, directly acts on the edge of the metal sheet blank, and applies constraint pressure; the resistance heating rod is connected to the constraint block, and the sheet to be formed is heated through the constraint block; the motor is connected to the motor fixing plate, and the motor fixing plate is connected to the base through bolts, and the output shaft of the motor is connected to the wire cylinder through a coupling, and the wire cylinder cooperates with the slider, and when the motor rotates, it drives the wire cylinder to rotate, thereby driving the slider and the moving platform to move along the guide rail; the power of the resistance heating rod is 1-2kW.

5. The robot mirror image forming device with a local constraint mechanism according to claim 1, characterized in that: The collaborative motion control system of the device includes a central controller, a control console and cables; the central controller is connected to the mirror forming processing system, the mobile constraint block pressing system and the blank fixing tooling system through cables, and is used to receive feedback information from each system, and issue control instructions according to a preset program to coordinate the actions of each system. The cable adopts a shielded cable to reduce signal interference; the control console is connected to one side of the central controller, and is used for the operator to input control instructions and set processing parameters and motion trajectories.

6. A forming method of a robot mirror forming device with a local constraint mechanism according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. The metal sheet blank is subjected to a solution treatment in a heating furnace and kept warm to obtain a uniform microstructure with good plasticity, and then transferred to room temperature clean water to cool to room temperature; S2, fixing the cooled metal sheet blank to the blank fixing fixture system, moving the constraint block to be close to the blank by moving the constraint block edge holding system, and heating the metal sheet blank to the target temperature by using the resistance heating rod in the constraint block; S3. After the metal sheet blank is heated to the target temperature, the mobile platform drives the constraint blocks to move to both sides of the heating area, and the horizontal cylinder pushes the constraint blocks to press the blank and apply the blank holding force; then the robot trajectory is planned through the device collaborative motion control system, and the forming loading tool of the mirror forming processing system is controlled to perform hot forming on the heating area to form complex local small features; S4, repeat S3 until all the complex small features are formed, then cool the preform to room temperature, unload the blank holding force, take out the preform for aging treatment, and finally cut off the excess to finally obtain a metal formed component.

7. A forming method of a robot mirror forming device with a local constraint mechanism according to claim 6, characterized in that: In S1, the temperature of the solution treatment of the metal sheet blank is 450-500°C, the solution treatment time is not less than 30 minutes, the insulation time of the metal sheet blank after the solution treatment is 20-40 minutes, and the transfer time of transferring the metal sheet blank after the solution treatment to clean water through a transfer tool is 3-10 seconds.

8. The forming method of the robot mirror forming device with a local constraint mechanism according to claim 6, characterized in that: In S2, the target temperature is 20-500°C.

9. The forming method of the robot mirror forming device with a local constraint mechanism according to claim 6, characterized in that: In S3, the horizontal cylinder pushes the constraint block to press the blank, the applied blank holding force is 0-5t, the rotation speed of the forming loading tool is 0-1000rpm, the punch feed rate of the mirror forming processing system is 1000-2000mm / min, and the applied forming force is 0-5000N.

10. The forming method of the robot mirror forming device with a local constraint mechanism according to claim 6, characterized in that: In S4, the aging treatment process of the preform is as follows: the taken-out preform is placed in an aging furnace at a temperature of 100-200° C. for insulation for a period of 6-36 hours.

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