An Adaptive Fixture System and Machining Method

Abstract

An adaptive fixture system and a machining method. The system includes a positioning and clamping module, an adaptive clamping module, a temperature control system, a reset device, and a bearing base plate. The adaptive clamping module uses phase change materials to achieve adaptive adjustment of the height and angle of the support shaft, compensating for workpiece machining deformation. The temperature control system controls the state switching of the phase change materials through fluid medium circulation, realizing controllable floating and precise pose locking of the support shaft. The reset device resets the support shaft to be coplanar with the positioning and clamping module during the finish machining stage to ensure machining accuracy. The present invention can solve the problems of large machining deformation of workpieces and overcutting of part dimensions, improve the machining deformation accuracy and dimensional accuracy of workpieces, and increase the yield rate of workpieces. By means of the method of gradually adapting the adaptive fixture, the influence of gravity sag of large thin-walled parts is offset. The machining method maximizes the function of the adaptive fixture, ensuring machining deformation accuracy and dimensional accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent manufacturing, and particularly to an adaptive fixture system and a machining method. Background Art

[0002] With the rapid development of the aviation industry, the requirements of aircraft for high mobility, high load and high reliability are becoming more and more prominent. Due to the characteristics of light weight and high strength of thin-walled structural parts, they have been widely used in the aerospace field. The use of integral thin-walled structural parts can also reduce the number of parts, the workload of the assembly process, and the connecting parts, thereby greatly improving the strength and assembly efficiency of the fuselage. Although the use of thin-walled structural parts has many advantages, due to the complex shape of thin-walled structural parts and relatively low stiffness, the material removal rate often reaches more than 90%. As a large amount of material is removed, the initial residual stress state of the blank is broken, and the internal stress is redistributed, resulting in machining deformations such as bending, torsion and combined bending and torsion of thin-walled structural parts.

[0003] In the actual industrial application site, there are two ways to machine such large frame beam thin-walled parts. The first is to use pressing plates and bolts for clamping. The disadvantage of this traditional method is that: in the way of fixing with bolts and pressing plates, it cannot adapt to the deformation caused by the release of residual stress, and new clamping stress and clamping deformation will be introduced, making the deformation of the parts more uncontrollable. The second is to use floating clamping, which often uses vacuum adsorption. The disadvantages of this method are: first, when the part size is large but the wall thickness is very thin, it cannot solve the deformation caused by the self-weight of the part; second, floating clamping will cause uneven wall thickness of the web of the machined part and unqualified dimensional accuracy, and it is easy to cause over-cutting of the part.

[0004] It should be noted that the information disclosed in the above background art section is only used for understanding the background of the present application, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] The main object of the present invention is to overcome the defects existing in the above background art, and provide an adaptive fixture system and a machining method to solve the problems of large machining deformation of workpieces and over-cutting of part sizes.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] An adaptive fixture system, comprising:

[0008] A positioning and clamping module, configured to apply a rigid constraint to the fixed support position of the workpiece;

[0009] The adaptive clamping module includes a phase change material, an adjustable support shaft, and a temperature response unit. The phase change material realizes the adaptive adjustment of the height and angle of the support shaft through solid-liquid phase change to compensate for the machining deformation of the workpiece.

[0010] The temperature control system integrates heating and cooling units and controls the state switching of the phase change material through the circulation of a fluid medium.

[0011] The reset device, in the finish machining stage, by being installed on the adaptive clamping module and replacing the support shaft to become a new support plane, enables the entire adaptive clamping module to reach an accurate clamping state coplanar with the positioning and clamping module.

[0012] And a bearing base plate provides a modular integration interface for the positioning and clamping module, the adaptive clamping module, and the temperature control system.

[0013] Among them, the temperature response unit monitors the temperature of the phase change material in real time and feeds it back to the temperature control system, and realizes the controllable floating of the support shaft in the machining deformation adaptation stage and the precise pose locking in the reset stage through the coordinated action of the heating and cooling units.

[0014] Further, the phase change material is a low-melting-point alloy, and its phase change temperature range is 40 - 80 °C. The bottom of the adjustable support shaft is completely immersed in the low-melting-point alloy melt pool, and the top is connected to the workpiece process boss through a spherical bearing.

[0015] Further, the adjustable support shaft has a vertical adjustment stroke of ±5 mm and a multi-directional swing angle compensation ability of ±8°. A temperature sensor is provided at its bottom, and thermoelectric signal transmission is realized with a temperature display module through an aviation plug.

[0016] Further, the temperature control system includes an independently operating heating water tank and a refrigeration water tank, realizes the circulation of the heat conduction fluid with a flow rate of 4 m³ / h through a double pump group, and a hydraulic integrated valve block distributes the fluid to 6 groups of independently controlled water channels.

[0017] Further, the reset device is used to restore the adaptive clamping module to the same horizontal height as the positioning and clamping module, with a reset accuracy of 0.01 mm, and is used during the rigid clamping in the last finish machining of the part.

[0018] Further, the reset device is a circular ring part, and screw hole positions are provided around the circular ring part. The reset device is connected to the end cover of the adaptive clamping module through the screw hole positions and screws, and thus forms an integral structure with the adaptive clamping module; when the support shaft is in a freely movable state, after the reset device is installed in place, its upper plane with high flatness serves as a new support structure to replace the support shaft and play a supporting role.

[0019] Furthermore, the low melting point alloy is encapsulated in the brass inner cavity, a spiral flow channel structure is formed between the cavity and the fixture shell, and the flow channel inlet and outlet are pressure-sealed by a skeleton oil seal.

[0020] Furthermore, the bearing base plate provides an integrated interface for the positioning clamping module, the adaptive clamping module and the temperature control system.

[0021] Furthermore, the temperature response unit includes a K-type thermocouple, which monitors the temperature of the phase change material in real time and feeds back to the temperature control system.

[0022] Furthermore, the adaptive clamping module includes a fixture shell, a low-melting-point alloy, a support shaft, a bearing and a bearing seat. The fixture shell is an internal hollow structure, the low-melting-point alloy is encapsulated in the inner cavity of the fixture shell, and a spiral flow channel structure is formed between the inner cavity and the fixture shell, and the flow channel inlet and outlet are pressure-sealed by a skeleton oil seal; the bottom of the support shaft is completely immersed in the low-melting-point alloy molten pool, and the top is connected to the workpiece by bolts to adapt to the deformation of the workpiece in the floating clamping position and provide support; a temperature sensor is provided at the bottom of the support shaft, and the other end of the temperature sensor is integrated into the aviation plug, It is connected to the multi-channel temperature display screen in the temperature display module through an aviation plug to display the internal temperature of the fixture in real time; the middle part of the support shaft is installed in the bearing seat through the bearing; the reset device is mechanically linked with the support shaft to reset the support shaft to be coplanar with the positioning and clamping module during the finishing stage; the water control module in the temperature control system is connected to the spiral flow channel on the fixture housing through a hydraulic pipeline, and the hydraulic integrated valve block and the solenoid valve control the flow direction and flow of the heat transfer fluid, and the solid-liquid phase change of the low-melting-point alloy is controlled by delivering hot water and cold water, thereby realizing the loosening and tightening of the fixture.

[0023] A processing method using the adaptive fixture system comprises the following steps:

[0024] S1. Design the layout of fixed clamping points and floating clamping points based on the workpiece configuration, and construct a finite element analysis model including process bosses;

[0025] S2. Determine the processing stage where adaptive clamping needs to be activated through gravity deformation simulation, and trigger the gradual adaptation mechanism when the self-weight deformation exceeds the preset threshold;

[0026] S3. Use rigid clamping in the rough machining stage and reserve a predetermined thickness of machining allowance on the machining surface;

[0027] S4. Double-sided alternating machining is performed in the semi-finishing stage, and the support axis posture is controlled to dynamically match the workpiece deformation surface through the melting-solidification cycle of the phase change material;

[0028] S5. Before finish machining, install the reset device onto the adaptive clamping module, start the temperature control system to heat and unlock the adaptive clamping module so that the support shaft can move freely. After the installation of the reset device is completed, adjust the support shaft to make it flush with the upper plane of the reset device, and then cool to lock the adaptive clamping module, completing the reset of the adaptive clamping module. Use precise distance measurement feedback control to ensure that the upper plane of the reset device is coplanar with the positioning reference plane.

[0029] S6. Complete the final machining under the rigid clamping conditions with preset precision requirements and conduct full-size inspection.

[0030] In some embodiments, a machining method using an adaptive fixture system includes the following steps:

[0031] A. According to the actual size and shape of the workpiece, determine the position and size of the process boss, and design and determine the layout of the fixed clamping module and the adaptive clamping module at the clamping points.

[0032] B. Analyze the workpiece with the completed clamping layout through finite element simulation, analyze the influence of the self-weight of the workpiece at each stage on the deformation of the part, and determine the stage that needs to gradually adapt the clamping method and the specific number of adaptive clamping modules for gradual adaptation according to the analysis results.

[0033] C. Clamp using the traditional clamping scheme, mill the blank to a square and machine the process boss designed in step A, complete the rough machining of the front and back sides, and leave enough machining allowance.

[0034] D. Conduct semi-finish machining of the front and back sides of the workpiece, clamp using the positioning module and the adaptive module respectively, and use the adaptive clamping module to gradually adapt to the machining deformation of the workpiece in the previous stage during the machining process.

[0035] E. Conduct finish machining of the front and back sides of the workpiece, clamp using the positioning module and the adaptive module respectively, use the adaptive clamping module to gradually adapt to the machining deformation of the workpiece in the previous stage during the machining process, and leave enough machining allowance.

[0036] F. Before the last finish machining of the front and back sides, use the reset device to reset the adaptive clamping module and restore the adaptive module to the same plane as the positioning module.

[0037] G. Use the positioning module and the adaptive module for rigid clamping, machine the front and back sides of the workpiece to the designed dimensions, and finally, inspect the deformation of the part.

[0038] In some embodiments, the finite element simulation analysis is carried out according to the designed clamping layout. Fixed constraints are added to the clamping positions of the fixed clamping module, and standard gravity is globally added to analyze the sag deformation of the workpiece caused by its own weight at the current machining stage. When the deformation caused by the self-weight exceeds 30% of the deformation in the previous machining step, a step-by-step adaptive clamping method needs to be adopted.

[0039] In some embodiments, the machining steps include milling the square, rough machining the front side, rough machining the back side, the first semi-finishing machining of the front side, the second semi-finishing machining of the front side, the first semi-finishing machining of the back side, the second semi-finishing machining of the back side, the first finishing machining of the front side, the second finishing machining of the front side, the first finishing machining of the back side, the second finishing machining of the back side, the third finishing machining of the front side, and the third finishing machining of the back side. In-situ detection of the deformation of the part is carried out between machining processes.

[0040] In some embodiments, the sufficient machining allowance is at least 0.5 mm.

[0041] In some embodiments, the adaptive clamping module is an adaptive fixture based on a temperature phase change material. The adaptive module is controlled by a temperature control device to loosen or tighten, and can adapt to the deformation of the workpiece in the vertical and horizontal directions.

[0042] In some embodiments, an adaptive fixture system includes:

[0043] A reset device for resetting the adaptive fixture system to the same clamping height.

[0044] A positioning and clamping module for positioning and clamping the workpiece at the fixed support position of the workpiece;

[0045] An adaptive clamping module for clamping the workpiece at the floating support position of the workpiece;

[0046] A temperature control system for controlling the loosening and tightening of the adaptive clamping module.

[0047] A bottom plate for installing the integrated interfaces of the laid-out positioning and clamping module, adaptive clamping module, and temperature control system.

[0048] In some embodiments, the adaptive clamping module includes a fixture housing, a low-melting-point alloy, a support shaft, bearings, a bearing block, and a reset device. The temperature control device includes a temperature display module, which includes a multi-channel temperature display screen, a temperature sensor, and an aviation plug integrated with a temperature sensing wire; a heating-cooling module, which includes a heating water tank and a refrigeration water tank; and a waterway control module, which includes a hydraulic pipeline, a hydraulic integrated valve block, and a solenoid valve. The low-melting-point alloy is installed inside the fixture housing, and hot water and cold water are conveyed through the waterway control module to control the loosening and tightening of the fixture; the low-melting-point alloy wraps the bottom of the support shaft, and the upper end of the support shaft is connected to the workpiece through bolts to adapt to the deformation of the workpiece at the floating clamping position and provide support; the temperature sensor is installed on the bottom surface of the support shaft, and the other end is integrated into the aviation plug and connected to the multi-channel temperature display screen through the aviation plug to display the temperature inside the fixture and provide a basis for the temperature control of the fixture.

[0049] In some embodiments, the reset device restores the adaptive clamping module to the same horizontal height as the fixed clamping module, and the reset accuracy can reach 0.01 mm, which is used for rigid clamping during the last finishing process of the part.

[0050] In some embodiments, the temperature sensor is a K-type thermocouple.

[0051] The present invention has the following beneficial effects:

[0052] The present invention provides an adaptive fixture system and a machining method, which can solve the problems of large machining deformation of workpieces and over-cutting of part sizes, improve the machining deformation accuracy and dimensional accuracy of workpieces, and improve the yield rate of workpieces.

[0053] The adaptive fixture system and machining method of the present invention have the following main technical advantages: it can dynamically adjust the clamping position according to the deformation of the workpiece after the previous machining, without introducing clamping deformation, so as to achieve stress-free clamping between processes; through the gradually adaptable clamping method, the influence brought by the self-weight of the part can be effectively prevented, making the deformation during the machining process more controllable, especially suitable for the machining deformation control of large thin-walled frame beam parts with poor rigidity; the continuous machining process arrangement on the same surface can maximize the role of the adaptive fixture in adapting to the deformation of the previous machining and optimize the machining effect; finally, the adaptive clamping system is reset through the reset device for rigid clamping, which can avoid over-cutting of the part, ensure the uniformity and dimensional accuracy of the workpiece size, and at the same time take into account the machining deformation accuracy and dimensional accuracy, significantly improving the yield rate of large thin-walled parts, and having important application value and good application prospects.

[0054] Other beneficial effects in the embodiments of the present invention will be further described below. Description of the Drawings

[0055] Figure 1 It is a flowchart of the method for machining thin-walled parts based on the gradual adaptation of an adaptive fixture according to an embodiment of the present invention.

[0056] Figure 2 It is a schematic structural diagram of the adaptive fixture system according to an embodiment of the present invention.

[0057] Figure 3 It is a schematic diagram of the deformation of the traditional machining method according to an embodiment of the present invention.

[0058] Figure 4 It is a schematic structural diagram of the workpiece according to an embodiment of the present invention.

[0059] Figure 5 It is a schematic diagram of the state of the workpiece during the machining process according to an embodiment of the present invention.

[0060] Figure 6 It is a schematic diagram of the self-weight deformation of the workpiece in the gradual adaptation method according to an embodiment of the present invention.

[0061] Figure 7A It is a schematic structural diagram of the adaptive module without the installation of the reset device according to an embodiment of the present invention.

[0062] Figure 7B It is a schematic structural diagram of the adaptive module with the installation of the reset device according to an embodiment of the present invention.

[0063] Figure 8A It is a sectional view of the reset device according to an embodiment of the present invention.

[0064] Figure 8B It is a three-dimensional structural diagram of the reset device according to an embodiment of the present invention.

[0065] Figure 9 It is a comparison diagram of the machining deformation between the method of gradually adapting the adaptive fixture and the traditional machining method according to an embodiment of the present invention. Detailed implementation manners

[0066] The following provides a detailed description of the embodiments of the present invention. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope of the present invention and its applications.

[0067] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, the connection can be for a fixing function or for a coupling or communication function.

[0068] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0069] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0070] Referring to Figure 1 , Figure 2 and Figures 4 to 7B , an adaptive fixture system provided by an embodiment of the present invention includes: a positioning and clamping module 3 for applying a rigid constraint to the fixed support position of the workpiece 1; an adaptive clamping module 4 including a phase change material, an adjustable support shaft 13, and a temperature response unit, wherein the phase change material realizes the adaptive adjustment of the height and angle of the support shaft 13 through solid-liquid phase change to compensate for the machining deformation of the workpiece; a temperature control system 6 integrating heating and cooling units to control the state switching of the phase change material through the circulation of a fluid medium; a reset device 2, in the finish machining stage, by being installed on the adaptive clamping module 4 and replacing the support shaft 13 to become a new support plane, enabling the entire adaptive clamping module 4 to reach an accurate clamping state coplanar with the positioning and clamping module 3; and a bearing base plate 5 providing a modular integration interface for the positioning and clamping module 3, the adaptive clamping module 4, and the temperature control system 6; wherein, the temperature response unit monitors the temperature of the phase change material in real time and feeds it back to the temperature control system 6, and realizes the controllable floating of the support shaft 13 in the machining deformation adaptation stage and the accurate pose locking in the reset stage through the coordinated action of the heating and cooling units.

[0071] In a preferred embodiment, the phase change material is a low melting point alloy 12, and its phase change temperature range is 40 - 80 °C. The bottom of the adjustable support shaft 13 is completely immersed in the molten pool of the low melting point alloy, and the top is connected to the workpiece process boss through a spherical bearing 17.

[0072] In a preferred embodiment, the adjustable support shaft 13 has a vertical adjustment stroke of ±5 mm and a multi-directional swing angle compensation ability of ±8°. A temperature sensor is provided at its bottom, and thermoelectric signal transmission is realized with a temperature display module through an aviation plug.

[0073] In a preferred embodiment, the temperature control system 6 includes a heating water tank (100°C ± 2°C) and a refrigerating water tank (20°C ± 2°C) that operate independently. A double pump group is used to achieve a heat transfer fluid circulation with a flow rate of 4 m³ / h. The hydraulic integrated valve block distributes the fluid to 6 independently controlled water channels.

[0074] In a preferred embodiment, the reset device 2 is used to restore the adaptive clamping module 4 to the same horizontal height as the positioning clamping module 3, with a reset accuracy of 0.01 mm, and it is used during the rigid clamping in the last finishing process of the part.

[0075] Refer to Figure 8A and Figure 8B In a preferred embodiment, the reset device 2 is a circular ring part. There are screw holes around the circular ring part. The reset device 2 is connected to the adaptive clamping module 4 through the screw holes by screws, and thus forms an integral structure with the adaptive clamping module 4. When the support shaft is in a freely movable state and the reset device is installed in place, its upper plane with high-precision flatness serves as a new support structure to replace the support shaft and play a supporting role.

[0076] The top of the support shaft 13 is provided with a threaded hole adapted to the process boss of the workpiece. When the support shaft is in a freely movable state, the process boss of the workpiece is connected and fastened to the threaded hole of the support shaft by screws. When the temperature control system makes the phase change material in a solid state, the adaptive clamping module is in a locked clamping state, and the reset device cooperates with the adaptive clamping module to make the whole adaptive clamping module have an accurate coplanar structural relationship with the positioning clamping module.

[0077] In a preferred embodiment, the low melting point alloy 12 is encapsulated in the brass inner cavity, and a spiral flow channel structure is formed between the cavity and the fixture housing 11. The inlet and outlet of the flow channel are pressure-sealed through a skeleton oil seal.

[0078] In a preferred embodiment, the bearing bottom plate 5 provides an integrated interface for the positioning clamping module 3, the adaptive clamping module 4, and the temperature control system 6.

[0079] In a preferred embodiment, the temperature response unit includes a K-type thermocouple, which monitors the temperature of the phase change material in real time and feeds it back to the temperature control system 6.

[0080] Figure 7A and Figure 7BThey are respectively a schematic diagram of the adaptive module structure without a reset device installed and a schematic diagram of the adaptive module structure with a reset device installed. In a preferred embodiment, the adaptive clamping module 4 includes a fixture shell 11, a low-melting-point alloy 12, a support shaft 13, a bearing 17 and a bearing seat 18. The fixture shell 11 is an internal hollow structure. The low-melting-point alloy 12 is encapsulated in the inner cavity of the fixture shell 11, and a spiral flow channel structure is formed between the inner cavity and the fixture shell 11. The flow channel inlet and outlet are pressure-sealed by a skeleton oil seal 15; the bottom of the support shaft 13 is completely immersed in the low-melting-point alloy molten pool, and the top is connected to the workpiece by bolts to adapt to the deformation of the workpiece in the floating clamping position and provide support; a temperature sensor is provided at the bottom of the support shaft 13, and the other end of the temperature sensor is integrated The support shaft 13 is connected to an aviation plug and is connected to a multi-channel temperature display screen in a temperature display module through the aviation plug, so as to display the internal temperature of the fixture in real time; the middle part of the support shaft 13 is installed in the bearing seat 18 through the bearing 17; the reset device 2 is mechanically linked with the support shaft 13, so as to reset the support shaft 13 to be coplanar with the positioning and clamping module 3 during the finishing stage; the water control module in the temperature control system 6 is connected to the spiral flow channel on the fixture housing 11 through a hydraulic pipeline, and the hydraulic integrated valve block and the solenoid valve control the flow direction and flow rate of the heat transfer fluid, and the solid-liquid phase change of the low melting point alloy 12 is controlled by delivering hot water and cold water, thereby realizing the loosening and tightening of the fixture.

[0081] like Figure 8A and Figure 8BAs shown in the figure, specifically, the reset device 2 is a circular ring part, and the flatness accuracy of its upper and lower planes is guaranteed to be within 0.01 mm. Screw holes are designed around it. In the finish machining stage, first, circulating hot water is delivered through the temperature control system. The hot water flows into the spiral flow channel on the fixture housing 11 through the hydraulic pipeline, heating the low-melting-point alloy 12 encapsulated in the inner cavity of the fixture housing 11. Since the low-melting-point alloy 12 undergoes a solid-liquid phase change when heated, changing from a solid state to a liquid state, the adaptive clamping module 4 is unlocked, and the state where the bottom of the support shaft 13 was originally fixed by the solid low-melting-point alloy is released, and it can move freely. At this time, screws are used to pass through the screw holes around the reset device 2 and connect it to the end cover of the adaptive clamping module 4, so that the reset device 2 and the adaptive clamping module 4 form an integral body. After the installation is completed, instead of using the top surface of the support shaft 13 as the support plane, the upper plane of the reset device undertakes the support function, and thus the reset of the adaptive clamping module is completed. Subsequently, screws are used to connect and fasten the process boss of the workpiece to the threaded hole at the top of the support shaft 13 to ensure that the workpiece is firmly connected to the adaptive clamping module. Then, the temperature control system delivers cold water, and the cold water also circulates through the spiral flow channel, causing the low-melting-point alloy 12 to cool and solidify again from a liquid state, and the adaptive clamping module 4 returns to the fastened state, completing the entire clamping process, making the overall adaptive clamping module and the positioning and clamping module in a coplanar precise structural relationship, providing stable clamping conditions for subsequent finish machining.

[0082] The embodiment of the present invention also provides a machining method using the above-mentioned adaptive fixture system, including the following steps:

[0083] S1. Based on the workpiece configuration, design the layout of the fixed clamping points and floating clamping points, and construct a finite element analysis model including the process boss;

[0084] S2. Determine the machining stage that requires activation of adaptive clamping through gravity deformation simulation, and trigger the step-by-step adaptation mechanism when the self-weight deformation amount exceeds the preset threshold;

[0085] S3. Adopt rigid clamping in the rough machining stage and reserve a predetermined thickness of machining allowance on the machining surface;

[0086] S4. Implement double-sided alternating machining in the semi-finish machining stage, and control the pose of the support shaft 13 to dynamically match the deformed surface of the workpiece through the melting-solidification cycle of the phase change material;

[0087] Before finish machining, install the reset device on the adaptive clamping module, start the temperature control system to heat and unlock the adaptive clamping module, the support shaft can move freely. After the installation of the reset device is completed, adjust the support shaft to make it flush with the upper plane of the reset device, and then cool to lock the adaptive clamping module, complete the reset of the adaptive clamping module, and use precise distance measurement feedback control to ensure that the upper plane of the reset device is coplanar with the positioning reference plane;

[0088] In a specific embodiment, before finish machining, the reset device is installed on the adaptive clamping module by screws. The temperature control system is started to heat by circulating hot water, so that the low-melting-point alloy in the adaptive clamping module melts and unlocks, and the support shaft can move freely. After the installation of the reset device is completed, the height of the support shaft is adjusted to be flush with the upper plane of the reset device. Then, the process boss and the threaded hole of the support shaft are connected and fastened by screws, and cold water is passed through to solidify the low-melting-point alloy, completing the reset of the adaptive clamping module;

[0089] S6. Finish the final machining under the rigid clamping condition with the preset precision requirement, and conduct full-size inspection.

[0090] The adaptive fixture system and method of the present invention can dynamically adjust the clamping position according to the deformation condition of the workpiece after the previous machining, without introducing clamping deformation, thereby realizing stress-free clamping between processes; through the gradually adaptive clamping method, the influence brought by the self-weight of the part can be effectively prevented, making the deformation in the machining process more controllable, especially suitable for controlling the machining deformation of large thin-walled frame beam parts with poor rigidity; the machining process arrangement of continuous same surface can maximize the role of the adaptive fixture in adapting to the deformation of the previous machining and optimize the machining effect; finally, the adaptive clamping system is reset by the reset device and rigid clamping is carried out, which can avoid overcutting of the part, ensure the uniformity and dimensional accuracy of the workpiece size, and take into account both the machining deformation accuracy and the dimensional accuracy, significantly improving the yield rate of large thin-walled parts, and having important application value and good application prospect.

[0091] The present invention offsets the influence of the gravity sag of large thin-walled parts through the gradually adaptive method of the adaptive fixture, maximizes the function of the adaptive fixture through the innovative machining process method, realizes the control of the machining deformation of the workpiece, ensures the shape accuracy of the workpiece machining, and through the high-precision reset device and the rigid clamping method, ensures the dimensional accuracy of the part. At the same time, it takes into account both the machining deformation accuracy and the dimensional accuracy, and ensures the yield rate of large thin-walled parts.

[0092] The following further describes the specific embodiments of the present invention.

[0093] In the embodiments of the present invention, the fixed clamping positions and floating clamping positions of the workpiece are designed based on the current workpiece configuration and machining deformation; the workpiece with the completed clamping layout is analyzed through finite element simulation to determine the gradually adaptable clamping scheme; the process bosses of the workpiece are machined and rough machined, leaving enough machining allowance on one side; semi-finishing machining of the front and back sides of the workpiece is carried out, and the positioning module and the adaptive module are respectively used for clamping. Two consecutive machining processes are carried out between each side. The adaptive clamping module is used between the machining processes to gradually adapt to the machining deformation of the workpiece in the previous stage; finish machining of the front and back sides is carried out. Two consecutive machining processes are carried out between each side. The adaptive clamping module is used between the machining processes to gradually adapt to the machining deformation of the workpiece in the previous stage, and enough machining allowance on one side for the last finish machining is left; the reset device is used to reset the adaptive clamping module, and rigid clamping is carried out to machine the workpiece to the designed dimensions. The present invention can improve the machining deformation accuracy and dimensional accuracy of the workpiece and improve the yield rate of the workpiece.

[0094] The important features and innovative advantages of the embodiments of the present invention include: First, the clamping position can be dynamically adjusted according to the deformation of the workpiece after the previous machining, without introducing clamping deformation, so as to achieve stress-free clamping between processes; Second, through the gradually adaptable clamping method, the influence brought by the self-weight of the part can be prevented; Third, the machining process of the same side continuously can maximize the role of the adaptive fixture, improve the machining deformation, and ensure the machining shape accuracy; Fourth, by using the reset device to reset the adaptive clamping system and carrying out rigid clamping, over-cutting of the part can be avoided, and the uniformity and dimensional accuracy of the workpiece size can be ensured.

[0095] An adaptive fixture reset device and its usage method include the following steps:

[0096] A. According to the actual size and shape of the workpiece, determine the position and size of the process boss, and design and determine the layout of the fixed clamping module and the adaptive clamping module at the clamping points.

[0097] Among them, the position of the process boss can be designed with an appropriate interval according to the size of the workpiece. The layout can distribute the bosses on both the inside and outside of the workpiece with reference to the part configuration. The machining allowance plan can be initially set according to experience.

[0098] B. Analyze the workpiece with the completed clamping layout through finite element simulation, analyze the influence of the self-weight of the workpiece at each stage on the part deformation, and determine the stage that needs to adopt the gradually adaptable clamping method and the specific number of adaptive clamping modules for gradual adaptation according to the analysis results.

[0099] Among them, according to the designed clamping layout, fixed constraints are added to the clamping positions of the fixed clamping module, and standard gravity is globally added in the finite element simulation to analyze the sag deformation caused by the self-weight of the workpiece in the current machining stage. When the deformation caused by the self-weight exceeds 30% of the deformation in the previous machining stage, a gradually adaptive clamping method needs to be adopted.

[0100] C. Clamp using the traditional clamping scheme, mill the blank to a square and machine the process boss designed in step A, complete rough machining on both the front and back sides, and leave enough machining allowance.

[0101] Among them, for the traditional clamping method, pads and pressure plates can be used. The sufficient machining allowance means that the unilateral machining allowance is at least twice the thickness of the thinnest web or more. The process boss needs to be finely machined to ensure flatness and surface roughness and is used as a positioning reference.

[0102] D. Perform semi-finishing machining on both the front and back sides of the workpiece, clamp using the positioning module and the adaptive module respectively, and use the adaptive clamping module between machining processes to gradually adapt to the machining deformation of the workpiece in the previous stage.

[0103] Among them, the gradually adaptive clamping method means that after a machining process is completed, the bolts at the clamping position need to be loosened to allow the workpiece to freely release the deformation. Before the start of the next machining process, hot water needs to be passed through the temperature control system to float the adaptive module to adapt to the deformation of the workpiece. During the process of melting and floating the adaptive module, all the adaptive modules cannot be melted at one time. It is necessary to evaluate the order and number of adaptive modules to be melted according to the finite element simulation results, and melt and clamp them one by one or multiple positions at a time to prevent the workpiece from losing support and deforming downward due to its own weight when melting all the adaptive modules at one time. During the clamping process, the connecting shaft of the adaptive module is fastened to the process boss of the workpiece with bolts. Since the low-melting-point alloy is melted at this time, the connecting shaft can support the workpiece at different heights and angles without introducing new clamping deformation. Then, cold water is passed through the temperature control system to solidify the low-melting-point alloy, and the adaptive module completes the clamping.

[0104] Among them, the machining process ensures that there are two consecutive machining operations on the same side for both semi-finishing machining of the front and back sides to fully utilize the function of the adaptive module to adapt to deformation.

[0105] E. Perform finish machining on both the front and back sides of the workpiece, clamp using the positioning module and the adaptive module respectively, use the adaptive clamping module between machining processes to gradually adapt to the machining deformation of the workpiece in the previous stage, and leave enough machining allowance.

[0106] Among them, the said sufficient machining allowance is at least 0.5 mm on one side, and the specific allowance can be determined according to the machining deformation of the previous two consecutive machining operations on the same side. The unilateral machining allowance is not less than the sum of the machining deformations of the previous two machining operations to prevent overcutting.

[0107] Before the last finishing process on both the front and back sides, use the reset device to reset the adaptive clamping module and restore the adaptive module to the same plane as the positioning module.

[0108] Among them, after all the previous processes are completed, only the last finishing process on the front side and the last finishing process on the back side remain. Install the reset device on the adaptive module to ensure that the support surface of the overall adaptive clamping system remains at the same height. At the same time, melt the adaptive module and restore the support shaft to the same height as the support surface of the reset device.

[0109] G. Use the positioning module and the adaptive module for rigid clamping, machine the front and back sides of the workpiece to the designed dimensions, and finally, detect the deformation of the part.

[0110] An adaptive fixture reset device and its usage method proposed in the embodiment of the present invention: First, it can dynamically adjust the clamping position according to the deformation of the workpiece after the previous processing, without introducing clamping deformation, thereby realizing stress-free clamping between processes. Compared with traditional processing methods, the present invention can adapt to and remove the deformation during the processing process, strengthen the controllability of the deformation during the part processing, reduce the processing deformation of the part product, and ensure the processing accuracy of the part; Second, through the gradually adaptive clamping method, the influence brought by the self-weight of the part can be prevented. Compared with the method of floating clamping with a vacuum chuck, the present invention adopts a gradually adaptive method to prevent the deformation brought by the self-weight of the part; Third, the processing technology of continuously machining the same surface can maximize the role of the adaptive fixture in adapting to the deformation of the previous processing. And by using the reset device to reset the adaptive clamping system and perform rigid clamping, overcutting of the part can be avoided, and at the same time, the processing deformation accuracy and dimensional accuracy of the workpiece can be ensured.

[0111] The gradually adaptive machining method of the adaptive fixture in the embodiment of the present invention is applicable to large thin-walled frame beam parts with a large material removal rate.

[0112] As Figure 2 shown, the embodiment of the present invention also provides an adaptive fixture system, including: a reset device for resetting the adaptive fixture system to the same clamping height; a positioning and clamping module for positioning and clamping the workpiece at the fixed support position of the workpiece; an adaptive clamping module for clamping the workpiece at the floating clamping position of the workpiece; a temperature control system for controlling the loosening and tightening of the adaptive clamping module; a bottom plate for installing the integrated interfaces of the positioned and clamped module, the adaptive clamping module, the temperature display, and the waterway control module arranged.

[0113] The reset device is used to restore the adaptive clamping module to the same horizontal height as the fixed clamping module, and the reset accuracy can reach 0.01 mm, which is used when performing rigid clamping in the last finishing process of the part.

[0114] The positioning and clamping module provides the functions of positioning, supporting and clamping for the workpiece, restricting the degrees of freedom of the workpiece in the horizontal and vertical directions. The adaptive clamping module is an adaptive clamping module based on low melting point alloy, which can adapt to the deformation of the workpiece in the vertical and horizontal directions. After being unlocked by heating with hot water, the adaptive clamping module has an adjustment stroke of ±5 mm in the thickness direction and an angular adjustment stroke of ±8°.

[0115] The adaptive clamping module includes a fixture housing, low melting point alloy, support shafts, inner cavity, skeleton oil seal, C-ring, fish-eye bearing, bearing seat and a reset device. The temperature control device includes a temperature display module, which includes a multi-channel temperature display screen, temperature sensors and an aviation plug integrating temperature sensing wires; includes a heating-cooling module, which includes a heating water tank and a refrigeration water tank; includes a waterway control module, which includes hydraulic pipelines, a hydraulic integrated valve block and solenoid valves. The low melting point alloy is installed inside the fixture housing, and hot water and cold water are conveyed through the waterway control module to control the loosening and fastening of the fixture; the low melting point alloy wraps the bottom of the support shaft, and the upper end of the support shaft is connected to the workpiece by bolts to adapt to the deformation of the workpiece at the floating clamping position and provide support; the temperature sensor is installed on the bottom surface of the support shaft, and the other end is integrated into the aviation plug and connected to the multi-channel temperature display screen through the aviation plug to display the temperature inside the fixture and provide a basis for the temperature control of the fixture. The temperature sensor can be a K-type thermocouple, but is not limited thereto.

[0116] The temperature control system includes a temperature display module, which is used to feedback the fixture temperature in real time during the fixture control process as the basis for loosening and fastening. The temperature display module has 16 external interfaces, 12 interfaces are used, and 4 interfaces are reserved. The temperature display range is 0-100 degrees Celsius. All temperature sensors are integrated into the aviation plug and connected to the display screen through a unified interface; a heating-cooling module, which is used to provide hot water and cold water for the fixture temperature control system. The cooling water pump group supplies water to meet a constant temperature of about 20°C, and the heating water pump group supplies water to meet a constant temperature of about 100°C at most. The flow rate of the two pump groups is 4m 3 / h; includes a waterway control module, which is used to meet different control requirements during the clamping process. Each pump group has 2 outlets, and the waterway is shunted through the hydraulic integrated valve block. There are 2 hydraulic integrated valve blocks, and each integrated valve block divides the waterway into 6 groups.

[0117] Embodiment 1:

[0118] As Figure 1 shown, this embodiment provides a method for using an adaptive fixture reset device, including the following steps:

[0119] Step 1: According to the actual size and shape of the workpiece, determine the position and size of the process boss, and design and determine the layout of the fixed clamping module and the adaptive clamping module at the clamping points.

[0120] The external dimensions of the workpiece are 1480mm×790mm×50mm. Refer to Figure 3 , for the existing machining deformation results of the workpiece, the deformation is relatively large at the two-arm positions and relatively small at the middle position. Refer to Figure 4 , the workpiece has a total of 17 process bosses. In the figure, 7a to 7l represent the process bosses. The process bosses are distributed on both the inner and outer sides of the workpiece. Among them, the middle five process bosses are fixed clamping positions, and each of the two arms has six process bosses as floating clamping points.

[0121] Step 2: B. Analyze the workpiece with the completed clamping layout through finite element simulation to analyze the influence of the self-weight of the workpiece at each stage on the deformation of the part, and determine the stage that needs to gradually adapt to the clamping method and the specific number of adaptive clamping modules for gradual adaptation according to the analysis results.

[0122] Refer to Figure 5 , after rough machining on the front side, the measured deformation is (-2, -0.034), and after the first semi-finishing machining on the front side, the measured deformation is (-0.29, 0.009). The maximum deformation results of the gravity finite element analysis for rough machining on the front side and the first semi-finishing machining on the front side are 0.158mm and 0.193mm respectively. The deformation caused by gravity after rough machining on the front side accounts for 8% of the residual stress deformation. Therefore, the influence of the deformation caused by gravity can be ignored in this machining stage. After loosening the locking bolts for aging, directly unlock all the adaptive modules by melting, and then clamp the workpiece by the clamping method of the adaptive modules to perform the first semi-finishing machining on the front side of the next machining process. The deformation caused by gravity after the first semi-finishing machining on the front side accounts for 64.5% of the residual stress deformation. Therefore, a gradually adapting clamping method needs to be adopted in this machining stage to prevent the deformation caused by gravity.

[0123] Step 3: Clamp the workpiece using the traditional clamping scheme, mill the blank to a square and machine the process bosses designed in Step A, and complete the rough machining on both the front and back sides, leaving a machining allowance of 6mm on each side.

[0124] Step 4: Perform semi-finishing machining on both the front and back sides of the workpiece, clamp the workpiece using the positioning module and the adaptive module respectively, and use the adaptive clamping module to gradually adapt to the machining deformation of the workpiece in the previous stage during the machining process. Perform two consecutive semi-finishing machining operations on the front side, with machining allowances of 4mm and 2mm respectively for the front side; perform two semi-finishing machining operations on the back side, with machining allowances of 4mm and 2mm respectively for the back side.

[0125] Refer to Figure 6, after the first rough machining on the front side is completed and before the second rough machining on the front side starts, by means of a step-by-step adaptation method, first melt the adaptive modules 5 and 6 on the left and right sides to adapt to the deformation of the adaptive clamping points at positions 5 and 6. The temperature control system passes hot water to heat the low-melting-point alloy in the adaptive clamping module. When the temperature display shows that the internal alloy temperature reaches above 75 °C, the fixture is unlocked. At this time, connect the connecting shaft to the process boss through bolts. After the connection is completed, pass cold water. When the temperature display shows that the temperature drops below 40 °C, the fixture is locked to complete the clamping of this process. Similarly, gradually adapt to the deformation at positions 3, 4 and positions 1, 2. Then the clamping steps for the second rough machining on the front side are completed, and the following rough machining steps are operated in the same way.

[0126] Reference Figure 7A and Figure 7B , the adaptive clamping module includes a fixture housing 11, a low-melting-point alloy 12, a support shaft 13, an inner cavity 14, a skeleton oil seal 15, a C-shaped retaining ring 16, a spherical plain bearing 17, a bearing seat 18 and a reset device 2. The structure of the adaptive clamping module is as follows. The adaptive clamping module is connected to the workpiece process boss through the support shaft 13. The bottom end of the connecting shaft is immersed in the low-melting-point alloy 12. The low-melting-point alloy is installed in the brass inner cavity 14. The heat / cold water flow channel is between the brass inner cavity and the fixture housing 11 and is sealed by the skeleton oil seal 15. The housing is connected to the temperature control system waterway through the water inlet pipe and the water outlet pipe. The upper end of the connecting shaft is equipped with a spherical plain bearing 17, which mainly plays a guiding role. The bearing seat 18 is used to install the bearing and the reset device 2. The reset device is installed on the bearing seat, and the height after installation is kept consistent with the designed height of the connecting shaft and is not used before the last finishing process. The temperature sensor is mounted in the middle of the connecting shaft to detect the temperature of the innermost low-melting-point alloy and is externally connected to the temperature display.

[0127] Step 5: Perform the finish machining on the front and back sides of the workpiece, and use the positioning module and the adaptive module for clamping respectively. During the machining process, use the adaptive clamping module to gradually adapt to the machining deformation of the workpiece in the previous stage. Perform two consecutive rough machining operations on the front side, with the front machining allowances being 1 mm and 0.5 mm respectively; perform two rough machining operations on the back side, with the back machining allowances being 1 mm and 0.5 mm respectively.

[0128] The clamping method is the same as that in Step 4.

[0129] Step 6: Before the last finish machining on the front and back sides, use the reset device to reset the adaptive clamping module to restore the adaptive module to the same plane as the positioning module.

[0130] Among them, after all the previous processes are completed, only the last front finish machining and back finish machining remain. Install the reset device on the adaptive module to ensure that the support surface of the overall adaptive clamping system remains at the same height. At the same time, melt the adaptive module and restore the support shaft to the same height as the support surface of the reset device. After installing the reset device, it is necessary to heat it through the hot water circulation of the temperature control system to unlock the adaptive clamping module. After connecting the workpiece to the connecting shaft with bolts, cool water is passed through to tighten it. The purpose of this step is to reset the adaptive clamping module to the same height and ensure that the connecting shaft is not higher than the reset device.

[0131] Step 7: Use the positioning module and the adaptive module for rigid clamping, machine the front and back sides of the workpiece to the designed dimensions, and finally, detect the deformation of the part.

[0132] Reference Figure 9 , the deformation of the adaptive fixture gradually adapting to the machining method is significantly smaller than that of the traditional machining method, indicating the effectiveness of the machining method of the present invention.

[0133] The present invention has the following advantages:

[0134] (1) The present invention realizes the control of the machining deformation of large-frame thin-wall parts through an adaptive fixture gradually adapting to the machining method. Compared with the traditional machining methods commonly used in the industrial field, the present invention has an obvious improvement effect on machining deformation, can improve the yield rate of large-frame thin-wall parts, and has a good application prospect in the field of machining large thin-wall parts.

[0135] (2) Through the gradually adapting clamping method, the present invention can prevent the influence brought by the self-weight of the part, make the deformation in the machining process more controllable, and is especially suitable for the control of the machining deformation of large thin-wall frame beam parts with poor rigidity.

[0136] (3) The present invention can carry out the machining of two consecutive same surfaces through the adaptive principle and reasonable machining process arrangement, give full play to the role of the adaptive fixture in adapting to the deformation of the previous machining, optimize the machining effect, and perform rigid clamping in the last finish machining step to ensure the dimensional uniformity of the part. At the same time, it takes into account both the machining deformation accuracy and the dimensional accuracy, and has important significance in the field of machining thin-wall structural parts.

[0137] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, they can also make several substitutions or modifications to these described embodiments, and these substitution or modification methods should all be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. Without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of protection of the patent application.

Claims

1. An adaptive fixture system, characterized in that: include: A positioning clamping module is used to apply rigid constraints at fixed support positions of the workpiece; An adaptive clamping module, comprising a phase change material, an adjustable support shaft and a temperature response unit, wherein the phase change material realizes adaptive adjustment of the height and angle of the support shaft through solid-liquid phase change to compensate for workpiece processing deformation; A temperature control system, integrating heating and cooling units, controlling the state switching of the phase change material through the circulation of a fluid medium; A reset device, which, in the finishing stage, is installed on the adaptive clamping module and replaces the support shaft to become a new support plane, so that the adaptive clamping module as a whole reaches a precise clamping state coplanar with the positioning clamping module; and a bearing base plate, providing a modular integration interface for the positioning clamping module, the adaptive clamping module and the temperature control system; The temperature response unit monitors the temperature of the phase change material in real time and feeds back to the temperature control system, and realizes the controllable floating of the support shaft in the processing deformation adaptation stage and the precise posture locking in the reset stage through the synergistic effect of the heating and cooling units; The adaptive clamping module includes a fixture shell, a low-melting-point alloy, a support shaft, a bearing and a bearing seat. The fixture shell is an internal hollow structure. The low-melting-point alloy is encapsulated in the inner cavity of the fixture shell, and a spiral flow channel structure is formed between the inner cavity and the fixture shell. The flow channel inlet and outlet are pressure-sealed by a skeleton oil seal; the bottom of the support shaft is completely immersed in the low-melting-point alloy molten pool, and the top is connected to the workpiece by bolts to adapt to the deformation of the workpiece in the floating clamping position and provide support; a temperature sensor is provided at the bottom of the support shaft, and the other end of the temperature sensor is integrated into the aviation plug. The blank plug is connected to the multi-channel temperature display screen in the temperature display module to display the internal temperature of the fixture in real time; the middle part of the support shaft is installed in the bearing seat through the bearing; the reset device is mechanically linked with the support shaft to reset the support shaft to be coplanar with the positioning and clamping module during the finishing stage; the water control module in the temperature control system is connected to the spiral flow channel on the fixture housing through a hydraulic pipeline, and the hydraulic integrated valve block and the solenoid valve control the flow direction and flow of the heat transfer fluid, and the solid-liquid phase change of the low-melting-point alloy is controlled by delivering hot water and cold water, thereby realizing the loosening and tightening of the fixture.

2. The adaptive fixture system according to claim 1, characterized in that The phase change material is a low melting point alloy, and its phase change temperature range is 40-80° C. The bottom of the adjustable support shaft is completely immersed in the low melting point alloy molten pool, and the top is connected to the workpiece process boss through a fisheye bearing.

3. The adaptive fixture system according to claim 2, characterized in that The adjustable support shaft has a ±5mm vertical adjustment stroke and ±8° multi-directional swing angle compensation capability. A temperature sensor is provided at the bottom thereof, and thermoelectric signal transmission is realized through an aviation plug and a temperature display module.

4. The adaptive fixture system according to claim 1, characterized in that The temperature control system comprises a heating water tank and a cooling water tank which operate independently, and a heat transfer fluid circulation is realized by a double pump group, and a hydraulic integrated valve block distributes the fluid to a plurality of independently controlled water channels.

5. The adaptive fixture system according to claim 1, characterized in that The resetting device is used to restore the adaptive clamping module to the same level as the positioning clamping module, and the resetting accuracy reaches 0.01mm.

6. The adaptive fixture system according to claim 1, characterized in that The reset device is a circular ring part with screw holes arranged around it. The reset device is connected to the adaptive clamping module through the screw holes and screws, thereby forming an integrated structure with the adaptive clamping module. When the support shaft is in a freely movable state, after the reset device is installed in place, its upper plane with high-precision flatness serves as a new supporting structure, replacing the support shaft to play a supporting role.

7. The adaptive fixture system according to claim 2, characterized in that: The low melting point alloy is encapsulated in the brass inner cavity, a spiral flow channel structure is formed between the cavity and the fixture shell, and the flow channel inlet and outlet are pressure-sealed by a skeleton oil seal.

8. The adaptive fixture system according to claim 1, characterized in that The temperature response unit includes a K-type thermocouple, which monitors the temperature of the phase change material in real time and feeds back to the temperature control system.

9. A processing method using the adaptive fixture system according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Design the layout of fixed clamping points and floating clamping points based on the workpiece configuration, and construct a finite element analysis model including process bosses; S2. Determine the processing stage where adaptive clamping needs to be activated through gravity deformation simulation, and trigger the gradual adaptation mechanism when the self-weight deformation exceeds the preset threshold; S3. Use rigid clamping in the rough machining stage and reserve a predetermined thickness of machining allowance on the machining surface; S4. Double-sided alternating machining is performed in the semi-finishing stage, and the support axis posture is controlled to dynamically match the workpiece deformation surface through the melting-solidification cycle of the phase change material; S5. Before finishing, install the reset device to the adaptive clamping module, start the temperature control system to heat the adaptive clamping module to unlock it, and the support shaft can move freely. After the reset device is installed, adjust the support shaft to make it flush with the upper plane of the reset device, and then cool it to lock the adaptive clamping module to complete the reset of the adaptive clamping module. Use precision distance measurement feedback control to ensure that the upper plane of the reset device is coplanar with the positioning reference plane; S6. Complete final processing under rigid clamping conditions with preset accuracy requirements and conduct full-size inspection.

Images