Pre-deformation clamping system and workpiece machining method

Abstract

A pre-deformation clamping system and workpiece machining method are disclosed. The pre-deformation clamping system includes a fixing module and a prestressing application module. The fixing module is configured to fix a fixed part of the workpiece. Multiple prestressing application modules are provided, each configured as a clamping part for clamping the workpiece. Each prestressing application module is configured to adjust the vertical position of its clamping part, thereby applying prestress to the workpiece to induce pre-deformation. The technical solution provided by the embodiments of this application can effectively improve the machining accuracy of the workpiece.

Description

Technical Field

[0001] This article relates to the field of parts processing technology, and in particular to a pre-deformation clamping system and workpiece processing method. Background Technology

[0002] Many components, such as the pre-stretched aluminum alloy plates commonly used in helicopter load-bearing structures, are typically integral frame beam structures with wall thicknesses below 2mm, making them typical thin-walled parts. The processing deformation of these thin-walled parts is a key issue restricting assembly accuracy and service performance. During the manufacturing process of aluminum alloys, processes such as quenching create self-balancing and non-uniformly distributed residual stresses within the material. During the processing of thin-walled parts, the significant material removal disrupts the initial equilibrium of residual stresses in the blank, releasing internal stresses and causing a re-equilibrium state. This leads to processing deformation, resulting in parts that do not meet standards, requiring manual reshaping and repair, or even complete scrapping. Summary of the Invention

[0003] The embodiments of this application provide a pre-deformation clamping system and a workpiece processing method to solve the problem of deformation of parts caused by the release of internal stress during the current processing of parts.

[0004] Embodiments of this application provide a pre-deformation clamping system, including: a fixing module and a prestressing application module;

[0005] The fixing module is configured to fix the fixing parts of the workpiece;

[0006] The prestressing application module is provided in multiple ways, and each prestressing application module is configured as a clamping part for clamping the workpiece;

[0007] Each prestressing module is configured to adjust the vertical position of the clamping part to apply prestress to the workpiece so that the workpiece is pre-deformed.

[0008] In one embodiment, a displacement detection device is further provided for each prestressing module. The displacement detection device is configured to detect the amount of vertical displacement of the clamping part of the workpiece caused by the prestress applied by the prestressing module.

[0009] In one embodiment, the prestressing application module includes a moving component and a driving mechanism for driving the moving component to move up and down, wherein the moving component is configured to clamp the clamping part;

[0010] The displacement detection device includes a sensor bracket and a displacement sensor mounted on the sensor bracket. The displacement sensor is configured as a contact sensor. The moving component includes a sensor contact element, and the detection head of the displacement sensor elastically contacts the sensor contact element.

[0011] In one embodiment, the prestressing application module includes a moving component and a driving device for driving the moving component to move up and down, wherein the moving component is configured to clamp the workpiece;

[0012] The driving device includes a lead screw, a lead screw nut mounted on the lead screw, and a power application mechanism for driving the lead screw to rotate. The moving component is fixed to the lead screw nut.

[0013] In one embodiment, the moving component includes a sleeve that is fitted onto the top of the lead screw and can move up and down relative to the lead screw. The sleeve is provided with a connecting post. The clamping part of the workpiece is fitted onto the connecting post and locked onto the connecting post by a locking component to achieve clamping.

[0014] In one embodiment, the power application mechanism includes a turbine connected to the lead screw, a worm gear cooperating with the turbine, and a handwheel that drives the worm gear to rotate.

[0015] In one embodiment, three fixing modules are provided, and the three fixing modules fix three fixing parts of the workpiece respectively.

[0016] In one embodiment, the fixing module is provided with a positioning post, and the fixing part is fitted onto the positioning post and locked to the positioning post by a locking component to achieve the fixing of the fixing part.

[0017] Embodiments of this application also provide a workpiece processing method, the method comprising: a prestress loading step and a subsequent processing step; wherein, the prestress loading step comprises:

[0018] The workpiece is clamped using the pre-deformation clamping system described above; wherein, the workpiece is first fixed using the fixing module, and then the prestressing module is used to clamp multiple clamping points of the workpiece respectively.

[0019] Based on the predicted deformation of the workpiece, the prestressing module is used to adjust the vertical position of the clamping part of the workpiece, thereby applying prestress to the workpiece so that the workpiece produces a pre-deformation in the same direction as the predicted deformation.

[0020] The subsequent processing step is: after the prestressing module applies prestress to the workpiece, the workpiece is processed.

[0021] In one embodiment, the method further includes a pre-processing step of processing the workpiece before the prestressing loading step, and an aging treatment step of aging the workpiece after the pre-processing step and before the prestressing loading step.

[0022] Following the subsequent processing step, the method further includes:

[0023] Release the pre-deformation clamping system from the workpiece and perform deformation detection on the processed workpiece.

[0024] In the technical solution provided by the embodiments of this application, the part of the workpiece fixed by the fixing module can be used as the machining reference. By fixing the workpiece by the fixing module, it is determined that the machining reference does not change during the entire machining process. Then, according to the predicted deformation of the workpiece, the pre-deformation loading module is used to adjust the multiple clamping parts of the workpiece up and down to apply prestress to the workpiece so that the workpiece produces pre-deformation in the same direction as the predicted deformation. Then the workpiece is machined. After machining is completed and the fixture releases the workpiece, the pre-deformation of the workpiece rebounds. This rebound is opposite to the pre-deformation generated by loading and the predicted deformation. In this way, the predicted deformation that the workpiece may produce due to internal prestress can be corrected, reducing the actual deformation of the workpiece caused by its internal residual stress, thereby effectively improving the machining accuracy of the workpiece.

[0025] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0026] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0027] Figure 1 This is a schematic diagram of the pre-deformation clamping system according to one embodiment of this application;

[0028] Figure 2 This is a schematic diagram of the prestressing application module according to one embodiment of this application;

[0029] Figure 3 for Figure 2 The diagram shown is a structural schematic of the prestressing application module in a disassembled state.

[0030] Figure 4 This is a schematic diagram of the structure of the fixing module according to one embodiment of this application;

[0031] Figure 5 This is a schematic diagram of the structure of the fixed base plate according to one embodiment of this application.

[0032] Explanation of reference numerals in the attached figures:

[0033] 10-Fixed base plate; 101-First elongated groove; 102-Second elongated groove; 20-Prestressing application module; 201-Mounting base; 202-Mounting housing; 2021-First housing section; 2022-Second housing section; 203-Worm gear; 204-Turbine; 205-First bearing; 206-Second bearing; 207-First end cover; 208-Second end cover; 209-Handwheel; 210-Lead screw; 211-Lead screw nut; 21 2-Set of components; 2121-Connecting post; 2122-Boss; 2123-Connecting flange; 213-Sensor contact; 214-End cap; 215-Third bearing; 216-Fourth bearing; 217-Sensor bracket; 218-Displacement sensor; 30-Fixing module; 301-Base; 3011-Connecting hole; 302-Support post; 303-Positioning post; 40-Workpiece; 401-Fixing part; 402-Clamping part. Detailed Implementation

[0034] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0035] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application can also be combined with any conventional features or elements to form unique inventive solutions. Any feature or element of any embodiment can also be combined with features or elements from other inventive solutions to form another unique inventive solution. Therefore, it should be understood that any feature shown and / or discussed in this application can be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes can be made within the scope of the appended claims.

[0036] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0037] During the machining of thin-walled parts, the initial equilibrium of residual stress in the blank is disrupted by the removal of a large amount of material. The internal stress is released and re-equilibrates, leading to workpiece deformation. Traditional mechanical clamping methods, such as clamping plates or vacuum chucks, are used to hold the workpiece. By uniformly removing material from both ends of the blank, the deformation caused by residual stress is made as symmetrical as possible, ensuring that the deformation is within acceptable limits. However, this method is time-consuming, labor-intensive, and highly dependent on material type and batch, making it unsuitable for actual production. Furthermore, when the workpiece wall thickness reaches a certain dimension, the overall rigidity of the workpiece becomes very low. Re-clamping with clamping plates or vacuum chucks introduces new clamping stress, causing secondary deformation of the workpiece. Therefore, adjustable clamping technology is crucial. There are also some flexible clamping technologies that use pneumatic or electric motors as power sources to achieve flexible clamping. However, pneumatic devices have high requirements for airtightness, and the clamping force of pneumatic devices is greatly affected by air pressure, which has certain limitations. Electric motor-driven flexible clamping devices have high requirements for control precision and cannot accurately achieve follow-up. They may introduce clamping stress during the re-clamping process, which also has certain drawbacks.

[0038] To address the problem of workpiece deformation caused by residual stress inside components, embodiments of this application provide a pre-deformation clamping system, such as... Figure 1 As shown, it includes: a fixing module 30 and a prestressing application module 20;

[0039] The fixing module 30 is configured to fix the fixing part of the workpiece 40;

[0040] Multiple prestressing application modules 20 are provided, and each prestressing application module 20 is configured as a clamping part 402 for clamping the workpiece 40;

[0041] Each prestressing module 20 is configured to adjust the vertical position of the clamping part 402, thereby applying prestress to the workpiece 40 to cause the workpiece 40 to undergo pre-deformation.

[0042] In the technical solution provided by the embodiments of this application, the part of the workpiece 40 that is fixed by the fixing module 30 can be used as a processing reference. By fixing the workpiece 40 by the fixing module 30, it is determined that the processing reference does not change during the entire processing process. Then, based on the predicted deformation of the workpiece 40 (the predicted deformation is the deformation of the workpiece 40 caused by the internal residual stress, which can be obtained through simulation or other means), the prestressing module 20 is used to adjust the multiple clamping parts 402 of the workpiece 40 up and down to apply prestress to the workpiece 40, so that the workpiece produces the same pre-deformation as the predicted deformation. That is, the prestress is the prestress in the same direction as the internal residual stress of the workpiece. Then the workpiece 40 is processed. After the processing is completed, the prestressing module 20 releases the workpiece 40, and the pre-deformation of the workpiece 40 rebounds. This rebound is opposite to the pre-deformation generated by loading and the predicted deformation. In this way, the predicted deformation that the workpiece may produce due to the internal prestress can be corrected, reducing the actual deformation of the workpiece caused by the internal residual stress, thereby effectively improving the processing accuracy of the workpiece.

[0043] In one embodiment, the pre-deformation clamping system further includes a displacement detection device corresponding to each prestressing module 20. The displacement detection device is configured to detect the vertical displacement of the clamping part 402 of the workpiece 40 caused by the prestress applied by the prestressing module 20. This displacement is the deformation of the workpiece 40 after being subjected to the applied prestress, which is in the same direction as the predicted deformation of the workpiece.

[0044] In an exemplary embodiment, the prestressing module 20 includes a moving component and a driving mechanism for driving the moving component to move up and down. The moving component is configured as a clamping part 402 for clamping the workpiece 40.

[0045] The displacement detection device includes a sensor bracket 217 and a displacement sensor 218 mounted on the sensor bracket 217. The displacement sensor 218 is a contact sensor, and the moving component includes a sensor contact 213. The detection head of the displacement sensor 218 elastically contacts the sensor contact 213. During the up-and-down adjustment of the clamping part 402 using the prestressing module 20, the displacement of the clamping part 402 can be obtained in real time through the displacement sensor 218. Specifically, the displacement sensor 218 can obtain the detection value before the prestressing module 20 applies prestress to the clamping part 402 and the detection value after the prestressing module 20 applies prestress, thereby obtaining the displacement of the clamping part 402. In one example, the measurement accuracy of the displacement sensor 218 can reach 0.01 mm, and the sampling frequency is 1000 Hz.

[0046] Figure 2 and Figure 3In the example shown, the prestressing application module 20 includes a moving component and a driving device for driving the moving component to move up and down. The moving component is configured as a clamping part 402 capable of clamping the workpiece 40. The driving device includes a lead screw 210, a lead screw nut 211 mounted on the lead screw 210, and a power application mechanism for driving the lead screw 210 to rotate. The moving component is fixed to the lead screw nut 211, and the lead screw nut 211 drives the moving component and the clamping part 402 on the moving component to move up and down.

[0047] The moving component includes a sleeve 212 that is fitted onto the top of the lead screw 210 and can move up and down relative to the lead screw 210. A connecting post 2121 is provided on the sleeve 2121. The clamping portion 402 of the workpiece 40 is fitted onto the connecting post 2121 and locked onto the connecting post 2121 by a locking component to achieve clamping. The clamping portion 402 may be a process boss with an opening provided on the workpiece 40.

[0048] In this example, the assembly 212 also includes a boss 2122 below the connecting post 2121 to support the clamping portion 402 fitted onto the connecting post 2121. The connecting post 2121 may have external threads to lock the clamping portion 402 onto the connecting post 2121 using a nut. Additionally, to facilitate the connection and fixation of the assembly 212 with the lead screw nut 211, the assembly 212 may also include a connecting flange 2123 below the boss 2122 to be fixed to the lead screw nut 211.

[0049] It is understandable that the clamping part 402 of the workpiece is not limited to being fitted onto the connecting column 2121. For example, the moving component is provided with a clamping mechanism, which can clamp the clamping part 402 of the workpiece.

[0050] In one embodiment, the power application mechanism that applies rotational power to the lead screw 210 includes a worm gear 204 connected to the lead screw 210, a worm 203 cooperating with the worm gear 204, and a handwheel 209 that drives the worm 203 to rotate. The worm gear mechanism can convert the rotation of the handwheel 209 into the axial movement of the lead screw 210, thereby facilitating the structural arrangement of the prestressing application module 20. Furthermore, by setting the worm gear mechanism to apply power to the lead screw 210, self-locking can be achieved; that is, the lead screw 210 can only be driven by rotating the handwheel 209, and cannot be directly rotated.

[0051] like Figure 2 and Figure 3In the example shown, the prestressing application module 20 includes a mounting housing 202 and a mounting base 201 located below the mounting housing 202. The mounting housing 202 includes a first housing part 2021 and a second housing part 2022 connected to each other. The first housing part 2021 is provided with a transversely arranged worm 203 and a first bearing 205 and a second bearing 206 located at opposite ends of the worm 203. The two ends of the first housing part 2021 along the axial direction of the worm 203 also have openings to facilitate the installation of components. The openings at both ends are respectively provided with a first end cover 207 and a second end cover 208. The handwheel 209 is connected to the worm 203 through the opening on the second end cover 208. A turbine 204 is provided inside the second housing part 2022. The worm gear 204 is fixed at the lower part of the vertically arranged lead screw 210. A third bearing 215 and a fourth bearing 216 are also provided inside the second housing part 2022 at both ends of the turbine 204 in the axial direction. A top opening is provided at the top of the second housing part 2022. An end cover 214 is provided at the top opening. The lead screw 210 extends upward from the end cover 214. A lead screw nut 211 is installed on the part of the lead screw 210 that extends out of the end cover 214.

[0052] exist Figure 2 and Figure 3 In one embodiment, the movable component connected to the lead screw nut 211 includes a sleeve 212 and a sensor contact 213. The sleeve 212 is axially movable and is sleeved on the top end of the lead screw 210. The connecting flange 2123 of the sleeve 212 is connected to the lead screw nut 211. The sensor contact 213 is sleeved on the sleeve 212 and is fixed to the lead screw nut 211 together with the connecting flange 2123. During the displacement of the sensor contact 213 with the lead screw nut 211, the displacement sensor 218 is always in contact with the sensor contact 213, so that the displacement of the clamping part 402 of the workpiece can be detected in real time.

[0053] In this example, the lead screw nut 211 drives the moving component to move up and down within a range of 10mm. This 10mm range of movement is sufficient to meet the requirements for workpiece deformation correction.

[0054] In one embodiment, three fixing modules 30 are provided, and the three fixing modules 30 fix three fixing parts 401 of the workpiece 40 respectively. Three points determine a plane, so the three fixing parts 401 can form a reference plane. This reference plane is used as a machining reference, and the pre-deformation amount generated by the workpiece 40 after applying prestress can be obtained using this reference plane.

[0055] like Figure 4In the example shown, the fixing module 30 is provided with a positioning post 303. The fixing part 401 is sleeved on the positioning post 303 and locked to the positioning post 303 by a locking component (e.g., a locking nut) to achieve the fixing of the fixing part 401. Of course, the fixing module 30 can also adopt other methods for positioning or fixing the workpiece, such as clamping. Moreover, the fixing module 30 is not limited to three, as long as it can fix the predetermined part of the workpiece so that the workpiece has a machining reference.

[0056] The fixing module 30 also includes a support column 302 disposed below the positioning column 303. The support column 302 and the positioning column 303 form a stepped structure for the fixing part 401 that supports the workpiece. A base 301 is disposed below the support column 302. A connection hole 3011 for installing the fixing module 30 is provided on the base 301.

[0057] In one embodiment, the pre-deformation clamping system may further include a fixed base plate 10, with the prestressing application module 20 and the fixing module 30 both fixed to the fixed base plate 10. By setting the fixed base plate 10, multiple prestressing application modules 20 and the fixing module 30 can be installed on the same horizontal plane. Of course, it is understood that the prestressing application module 20 and the fixing module 30, both fixed to the fixed base plate 10, can also be directly installed on a processing platform, such as on a machine tool.

[0058] Figure 5 In the example shown, the fixed base plate 10 is provided with a plurality of first elongated grooves 101 and a plurality of second elongated grooves 102, the length direction of the first elongated grooves 101 being perpendicular to the length direction of the second elongated grooves 102; wherein, the prestressing application module 20 and the fixing module 30 are fixed to the fixed base plate 10 by bolts passing through the corresponding first elongated grooves 101, and the fixed base plate 10 is fixed to the processing platform, such as a machine tool, by bolts passing through the second elongated grooves 102.

[0059] Embodiments of this application also provide a workpiece processing method, the method comprising: a prestressing loading step and a subsequent processing step; wherein,

[0060] The prestressing loading step includes:

[0061] The workpiece 40 is clamped using the pre-deformation clamping system described above; wherein, the workpiece 40 is first fixed using the fixing module 30, and then the multiple clamping parts 402 of the workpiece 40 are clamped using the prestressing application module 20 respectively.

[0062] Based on the predicted deformation of workpiece 40, the prestressing module 20 adjusts the vertical position of the clamping part 402 of workpiece 40 to apply prestress to workpiece 40, causing it to undergo pre-deformation in the same direction as the predicted deformation. After the prestressing module 20 releases workpiece 40, it rebounds in the opposite direction to the predicted deformation, thus correcting any predicted deformation that might occur due to internal prestress, reducing the actual deformation, and improving the machining accuracy of the workpiece.

[0063] A reference plane can be defined, for example, the plane defined by the three fixed parts 401 of the workpiece 40 can be used as the reference plane to measure the pre-deformation of each part of the workpiece under the action of the applied pre-stress. The pre-deformation can be approximately the same as the predicted deformation at the corresponding position.

[0064] The subsequent processing step is: after the prestressing module 20 applies prestress to the workpiece 40, the workpiece is processed.

[0065] The method further includes a pre-processing step of processing the workpiece before the prestressing loading step, and an aging treatment step of aging the workpiece after the pre-processing step and before the prestressing loading step.

[0066] Because the internal residual stress of workpiece 40 will be redistributed after the previous processing, aging treatment can make the internal residual stress of workpiece 40 reach a new equilibrium after the previous processing. However, even after the internal residual stress of workpiece 40 reaches a new equilibrium after aging treatment, deformations such as bending, twisting or bending-twist combination still exist.

[0067] After the workpiece has undergone aging treatment, a detection device can be used to measure the surface of workpiece 40 to obtain a deformation map of the workpiece. Based on the deformation map and the predicted deformation amount of the workpiece before the preceding processing, a strategy for the next step of pre-deformation of the workpiece and a subsequent processing strategy are formulated in order to process the workpiece to the qualified dimensions.

[0068] Among them, the next step is to formulate a pre-deformation strategy for the workpiece and a subsequent processing strategy. Specifically, the predicted deformation amount of the workpiece in the subsequent processing can be obtained based on the difference between the predicted deformation amount of the workpiece obtained before the previous processing and the deformation map of the workpiece. Based on the new predicted deformation amount, the prestressing module is used to apply prestress to the workpiece to reduce the deformation amount of the workpiece in the subsequent processing.

[0069] In one exemplary embodiment, the preliminary processing step includes:

[0070] The workpiece 40 is clamped on the pre-deformation clamping system with its first surface facing upwards. Then, the first surface of the workpiece 40 is machined to a predetermined size. Machining the first surface of the workpiece 40 to the predetermined size can be achieved by roughing only the first surface, leaving a certain machining allowance, or by roughing the first surface first and then finishing it to the design dimensions of the part. Because the workpiece 40 undergoes aging treatment after the preceding machining, the preceding machining can be the part that has a significant impact on the deformation of the workpiece 40.

[0071] When aging the workpiece 40 after the previous processing, the workpiece 40 is released from the pre-deformation clamping system and is not clamped to avoid affecting the release or redistribution of internal stress during processing.

[0072] In the prestressing loading step, a pre-deformation clamping system is used to clamp the workpiece 40, with the second surface of the workpiece 40 facing upwards, opposite to the first surface. In the subsequent processing step, the second surface of the workpiece 40 is processed. Specifically, after the deformation clamping system clamps the workpiece 40 in the prestressing loading step, the surface of the workpiece 40 can be further measured to see if its difference from the ideal position is within a certain range. If it is not within a certain range, it is further adjusted by the prestressing application module 20; if it is within a certain range, the subsequent processing step can proceed.

[0073] In an exemplary embodiment, after the subsequent processing steps, the method further includes: releasing the pre-deformation clamping system from the workpiece 40 and detecting the deformation of the processed workpiece to determine whether the workpiece's accuracy meets the requirements.

[0074] The following describes the specific process of machining a workpiece 40 according to a specific embodiment.

[0075] like Figure 1 In the example shown, the workpiece 40 to be processed is a three-frame structure (three frames are formed on one side). Since the deformation trend of the three-frame structure is a combination of bending and torsion deformation, the layout of the pre-deformation clamping system is as follows: four prestressing application modules 20 are distributed at the four corners of the workpiece 40, three fixing modules 30 are placed in the middle of the workpiece 40, and the three fixing parts 401 define a plane, taking the middle position of the workpiece 40 as the reference plane for the entire processing.

[0076] Step 1: Fix the blank, machine the required process bosses for fixing part 401 and clamping part 402, and mill the upper and lower surfaces of the blank, leaving a 2mm machining allowance on each surface.

[0077] Step 2: Place the workpiece 40 processed in Step 1 on the pre-deformation clamping system. First, use the three middle fixing modules 30 to fix the three fixing parts 401 of the workpiece 40. Then, use the prestressing application modules 20 at the four corners to clamp the clamping parts 402 of the workpiece 40.

[0078] Step 3, Pre-processing steps: The first surface of the clamped workpiece 40 at the top is roughed and finished to the design dimensions.

[0079] Step 4, Aging treatment: After the first surface is processed, loosen the clamping of the prestressing module 20 on the workpiece 40, flip the workpiece 40 over, and perform aging treatment on the workpiece 40 for a period of time to fully release the stress of the workpiece.

[0080] Step 5, Obtain the actual deformation: The surface of workpiece 40 is measured using a detection device to obtain the actual deformation of workpiece 40 after aging treatment, and a deformation diagram can be obtained based on the detected deformation. Based on the deformation diagram and the predicted deformation of the workpiece, the pre-deformation amount that the pre-stressing module 20 needs to apply to the workpiece in the subsequent pre-stressing loading step is obtained.

[0081] Step 6, Prestressing loading step: Based on the pre-deformation amount that the prestressing application module 20 needs to apply to the workpiece obtained in the above steps, the prestressing application module 20 is used to clamp the workpiece 40 at the clamping part 402 and apply prestress.

[0082] Step 7: Machin the second surface of workpiece 40 to the designed dimensions.

[0083] Step 8: Loosen the clamp and complete the machining. After machining, the process bosses that serve as the fixing part 401 and the clamping part 402 can be removed. Then, the machined workpiece 40 is placed on a coordinate measuring machine to perform deformation detection on the workpiece 40, thereby determining whether the workpiece 40 is qualified.

[0084] Since the first surface of workpiece 40 needs to be machined into a frame structure, while the second surface only needs to have 2mm of machining allowance removed, the deformation generated during the machining of workpiece 40 is mainly concentrated during the machining of the frame structure on the first surface. Therefore, after roughing and finishing the first surface, the workpiece 40 is subjected to aging treatment. After the residual stress generated during machining is released, the workpiece 40 basically reaches a stable state. Then, the deformation of the aging workpiece 40 is corrected by the prestressing module 20, so that the workpiece 40 that meets the accuracy requirements can be obtained.

[0085] It should be noted that the number and clamping position of the prestressing application module 20 and the fixing module 30 can be adapted to different types of workpieces.

[0086] Furthermore, the processing method can be adapted to different types of workpieces. For example, if both the first and second surfaces of workpiece 40 have frame structures, the frame structures on both surfaces can be rough-machined in the pre-processing stage before aging treatment, leaving machining allowances. Then, aging treatment is performed. After aging treatment, the deformation of the workpiece is detected, and prestress is applied to the workpiece through the prestressing module 20 based on the actual deformation. Then, the first surface is machined, and after flipping, the deformation is detected again. Then, prestress is applied to the workpiece again through the prestressing module 20. Repeatedly correcting the deformation of the workpiece can significantly improve the machining accuracy of the workpiece.

[0087] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0088] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0089] In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0090] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0091] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0092] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0093] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A pre-deformation clamping system arranged to clamp a workpiece to be machined, characterized in that, include: Fixing module and prestressing application module; The fixing module is configured to fix the fixing parts of the workpiece, and there are three fixing modules, which are configured to fix the three fixing parts of the workpiece respectively. The prestressing application module is provided in multiple ways, and each prestressing application module is configured as a clamping part for clamping the workpiece; Each prestressing module is configured to adjust the vertical position of the clamping part, thereby applying prestress to the workpiece so that the workpiece produces pre-deformation in the same direction as the predicted deformation caused by workpiece processing. This is to reduce the deformation of the workpiece caused by the breaking of the initial equilibrium state of the blank residual stress, the release of internal stress, and the return to equilibrium. The predicted deformation is the predicted deformation of the workpiece caused by the internal residual stress, and the predicted deformation is obtained through simulation.

2. The pre-strain clamping system of claim 1, wherein, It also includes a displacement detection device for each prestressing module, the displacement detection device being configured to detect the amount of vertical displacement of the clamping part of the workpiece caused by the prestress applied by the prestressing module.

3. The pre-strain clamping system of claim 2, wherein, The prestressing application module includes a moving component and a driving mechanism for driving the moving component to move up and down. The moving component is configured to clamp the clamping part. The displacement detection device includes a sensor bracket and a displacement sensor mounted on the sensor bracket. The displacement sensor is configured as a contact sensor. The moving component includes a sensor contact element, and the detection head of the displacement sensor elastically contacts the sensor contact element.

4. The pre-strain clamping system of claim 1, wherein, The prestressing application module includes a moving component and a driving device for driving the moving component to move up and down. The moving component is configured to clamp the workpiece. The driving device includes a lead screw, a lead screw nut mounted on the lead screw, and a power application mechanism for driving the lead screw to rotate. The moving component is fixed to the lead screw nut.

5. The pre-strain clamping system of claim 4, wherein, The moving component includes a sleeve that is fitted onto the top of the lead screw and can move up and down relative to the lead screw. The sleeve is provided with a connecting post. The clamping part of the workpiece is fitted onto the connecting post and locked onto the connecting post by a locking component to achieve clamping.

6. The pre-strain clamping system of claim 4, wherein, The power application mechanism includes a turbine connected to the lead screw, a worm gear cooperating with the turbine, and a handwheel that drives the worm gear to rotate.

7. The pre-strain clamping system of any of claims 1-6, wherein, The fixing module is provided with a positioning post, and the fixing part is fitted onto the positioning post and locked to the positioning post by a locking component to fix the fixing part.

8. A workpiece processing method, characterized by, The method includes: a prestressing loading step and a subsequent processing step; wherein, the prestressing loading step includes: The workpiece is clamped using the pre-deformation clamping system according to any one of claims 1-7; wherein, the workpiece is first fixed using the fixing module, and then the multiple clamping parts of the workpiece are clamped using the prestressing application module. Based on the predicted deformation of the workpiece, the prestressing module is used to adjust the vertical position of the clamping part of the workpiece and apply prestress to the workpiece so that the workpiece produces a pre-deformation in the same direction as the predicted deformation. The subsequent processing step is: after the prestressing module applies prestress to the workpiece, the workpiece is processed.

9. The workpiece processing method according to claim 8, characterized in that, The method further includes: a pre-processing step of processing the workpiece before the prestressing loading step; and an aging treatment step of aging the workpiece after the pre-processing step and before the prestressing loading step. Following the subsequent processing step, the method further includes: Release the pre-deformation clamping system from the workpiece and perform deformation detection on the processed workpiece.

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