Segmentation synchronous electrolytic machining apparatus and method for intake / exhaust edges of wings with large twist angles

Abstract

A segmented synchronous electrolytic machining apparatus and method for the intake / exhaust edges of an airfoil with a large helix angle is provided, wherein the intake / exhaust edges of an airfoil with a large helix angle are divided into two sections with smaller helix angles along a specific cross section, and two cathodes are designed for each section, thereby realizing segmented synchronous electrolytic machining of the intake / exhaust edges of an airfoil with a large helix angle using two cathodes with different feed directions. The apparatus includes a segmented synchronous feed mechanism, an airfoil tip tool cathode (16), and an airfoil root tool cathode (15). The segmented synchronous feed mechanism is mounted on the spindle of a machine tool, and a pair of wedge mechanisms can convert the unidirectional feed of the spindle into synchronous cross-feed of the two tool cathodes (15, 16). The two tool cathodes (15, 16) are mounted on the front end of the segmented synchronous feed mechanism, and a main liquid inlet and an auxiliary liquid inlet are provided on both the upper and lower sides of the cathode shell, respectively, forming an open electrolyte flow field together with the airfoil (12).

Description

Technical Field

[0001] The present invention belongs to the technical field of electrochemical machining, and particularly relates to a segmented synchronous electrochemical machining device and method for the intake edge / exhaust edge of a blade with a large twist angle.

Background Art

[0002] The blade is one of the important components of modern aeroengines. The blades of new aeroengines always adopt more and more complex structural forms such as wide chord, curved and swept airfoils. There are many blades, the curvature change of the blade surface is large, the ends are curved and swept, and the requirements for its geometric accuracy and overall quality are increasing. In particular, the requirements for dimensional accuracy and geometric shape at the intake edge / exhaust edge of the blade are becoming more and more stringent, and it is becoming more and more difficult to guarantee the forming process and surface integrity.

[0003] Currently, the main processing methods for the intake edge / exhaust edge include milling, grinding, and electrochemical machining. Milling is a processing method that removes workpiece material with a high-speed rotating milling cutter. With the development of multi-axis numerical control processing technology, the application range of milling has expanded, and currently, it can be applied to the precision machining of twisted structures such as the intake edge / exhaust edge of blades. However, since milling is a contact processing method, there is a macro cutting force between the cutter and the workpiece. When machining a small-sized intake edge / exhaust edge structure, workpiece deformation occurs, the machining accuracy decreases, and if the cutter shape, machining parameters are selected inappropriately, or the machining trajectory is planned unreasonably, phenomena such as tool marks and microcracks may occur on the workpiece surface. Grinding technology, as a precision finishing process, is always used for the precision machining of the intake edge / exhaust edge of blades. During machining, it is necessary to ensure a certain machining allowance in advance in the previous process for the intake edge / exhaust edge. By performing precision finishing of the intake edge / exhaust edge with precision grinding technology, an intake edge / exhaust edge structure with high precision and high surface quality can be machined. However, the current grinding process for the intake edge / exhaust edge is difficult to achieve automatic production, and further improvement in processing efficiency is required.

[0004] Electrolytic machining is a processing method that removes metal materials based on the principle of electrochemical anodic dissolution. During processing, the anode workpiece is connected to the positive electrode of the power supply, and the tool cathode is connected to the negative electrode of the power supply. An extremely small processing gap is maintained between the two electrodes, and the electrolyte flows through the gap at high speed. Due to the electric field, oxidation-reduction reactions occur on the surfaces of the two electrodes within the processing gap. An oxidation reaction occurs at the anode, removing the metal material in the form of ions, and a reduction reaction occurs at the cathode, depositing hydrogen. During processing, the tool cathode is continuously fed, continuously removing the material from the surface of the workpiece and gradually shaping it. Electrolytic machining belongs to the category of non-contact processing, is not limited by the mechanical properties of the material, and has the characteristics of having no cutting force or cutting heat. It has excellent advantages in processing small, thin-walled components and is very suitable for processing the intake / exhaust edges of blades.

[0005] Conventional methods for processing the intake / exhaust edge structure of an airfoil involve feeding the wing ventral cathode and wing dorsal cathode in relative directions to process the airfoil surface and simultaneously form the intake / exhaust edge structure. However, because the curvature of the intake / exhaust edge changes significantly compared to the airfoil surface, the electric field and flow field conditions at the intake / exhaust edge constantly change during actual processing, making it difficult to guarantee processing accuracy. The electrolytic machining method using tangential feeding for the intake / exhaust edge completes the processing of the mold surface, then feeds a tool cathode specifically for the intake / exhaust edge tangentially along the airfoil camber line to remove processing margins, thereby achieving precise machining of the intake / exhaust edge. This method has significant advantages over conventional bidirectional feeding methods in cathode design and flow field design, and has great potential for processing the intake / exhaust edges of airfoils.

[0006] The patent "Method for Designing Three Elements of Leading and Trailing Edge Cathodes for Precision Electrolysis of Aircraft Engine Wings" (Application No. 202210632192.2, Applicant: Jiangsu JiCui Precision Manufacturing Research Institute Co., Ltd., Inventors: Wang Zhongheng, He Chao, Zhao Jianshe, Zhang Changhao, Gao Weizheng) proposes designing the cathode using a preferred three-element design for leading and trailing edges, thereby reducing the number of iterative modifications to the cathode and improving the machining accuracy of the leading and trailing edges of the wing.

[0007] The patent "Method for Designing Precision Electrolytically Machined Electrodes at the Leading and Trailing Edges of an Air Wing" (Application No. 201711249203.4, Applicant: China Aerospace Shenyang Liming Aviation Engine Co., Ltd., Inventors: Liu Haibo, Huan Heng, Zheng Jin, Chen Dong, Zhang Yahua) modifies the surface conductivity of the cathode in the area where the leading and trailing edge electric fields are concentrated by surface treatment, thereby avoiding the problem of difficulty in guaranteeing electrolytic machining accuracy caused by electric field concentration and flow field turbulence in the leading and trailing edge regions.

[0008] The patent "Adaptive Machining Method for the Leading and Trailing Edges of an Aircraft Engine Turbo Wing" (Application No. 202110678545.8, Applicant: Jiangsu Jianghangzhi Aircraft Engine Parts Research Institute Co., Ltd., Inventors: Wu Jiang, Cao Chunxiao, Yan Xiaolin) describes how, by providing multiple driven mechanisms uniformly distributed within a oscillating mechanism, the tool cathode, internally provided leading edge cathode 1, and leading edge cathode 2 adaptively complete the precision electrolytic machining of the leading and trailing edges of the wing, significantly improving machining efficiency and accuracy.

[0009] The patent "Pulsating electrolytic modification apparatus for intake / exhaust edges of wings or integrated blisks" (application number 202110617149.4, applicant: Nanjing University of Aeronautics and Astronautics, inventors: Zhu Di, Liu Jia, Wang Hao, Wang Jingtao) proposes a pulsating electrolytic machining apparatus that performs tangential feed machining along intake / exhaust edges, enabling machining under conditions with a much smaller machining gap than normal, and significantly improving the contour accuracy of the intake / exhaust edges of wings.

[0010] The patent "Tool and Method for Precision Electrolytic Correction of Intake / Exhaust Edges of Wings" (Application No. 202210402862.1, Applicant: Nanjing University of Aeronautics and Astronautics, Inventors: Wang Jingtao, Liu Jia, Zhu Di, Xu Zhengyang, Wei Haodi, Wang Ying) proposes an integrated cathode for tangential feeding of intake / exhaust edges and a method for precision correction of intake / exhaust edges. This enables electrolytic machining of intake / exhaust edges without attaching or detaching tooling fixtures or tool alignment devices during processing, and improves the degree of automation of electrolytic machining of intake / exhaust edges to a certain extent.

[0011] However, current tangential feed electrolytic machining methods still have shortcomings in practical applications when machining airfoils with twisted airfoil shapes and large twist angles at the intake / exhaust edges. Currently, the cathode feed direction of the intake / exhaust edges is aligned with the angle bisector direction of the twist angle of the intake / exhaust edges. In the case of airfoils with excessively large twist angles, the cathode machining angle at certain parts of the intake / exhaust edges becomes too large, making it impossible to uniformly melt the arc of the intake / exhaust edges. Therefore, to overcome the challenge of not being able to achieve high-precision electrolytic machining of intake / exhaust edges of airfoils with large twist angles, the present invention provides a segmented synchronous electrolytic machining apparatus and method for intake / exhaust edges of airfoils with large twist angles. [Overview of the Initiative] [Problems that the invention aims to solve]

[0012] Specifically, the present invention employs the following technical solution, providing a segmentation synchronous electrolytic machining method for the intake / exhaust edges of an airfoil with a large helix angle, that is, segmentation synchronous machining is performed on an airfoil with a large helix angle, and the method for determining the segmented cross-section and the feed direction of the tool cathode after segmentation are determined in the following steps.

[0013] Step 1. Cut out the wingtip and wingroot cross-sectional contour lines from the 3D wing model and project them onto the same plane.

[0014] Step 2. Draw several inscribed circles on the projected contours of the wingtip and wingroot cross-sectional contour lines, respectively. Fit each of these inscribed circles to a camber line passing through its center, thereby forming the wingtip and wingroot cross-sectional camber lines.

[0015] Step 3. Draw a tangent line to the camber line at the intersection of the tip section camber line and the intake edge, pointing outwards from the cross-sectional contour, and call it the tip section camber line intake edge tangent. Draw a tangent line to the camber line at the intersection of the root section camber line and the intake edge, pointing outwards from the cross-sectional contour, and call it the root section camber line intake edge tangent. Draw a tangent line to the camber line at the intersection of the tip section camber line and the exhaust edge, pointing outwards from the cross-sectional contour, and call it the tip section camber line exhaust edge tangent. Draw a tangent line to the camber line at the intersection of the root section camber line and the exhaust edge, pointing outwards from the cross-sectional contour, and call it the root section camber line exhaust edge tangent.

[0016] Step 4. The angle bisector direction of the tangent line between the camber line and the intake edge at the wingtip section and the camber line and intake edge at the wing root section is defined as the reference direction. The airfoil section where the camber line tangent direction coincides with this reference direction is defined as the dividing surface of the intake edge. The angle bisector direction of the reference direction and the direction of the camber line and intake edge at the wingtip section is defined as the feed direction of the tool cathode on the wingtip side of the intake edge. The angle bisector direction of the reference direction and the direction of the camber line and intake edge at the wing root section is defined as the feed direction of the tool cathode on the wing root side of the intake edge. The reference direction is defined as the angle bisector direction of the camber line tangent to the exhaust edge at the wingtip section and the camber line tangent to the exhaust edge at the wing root section. The airfoil section where the camber line tangent direction coincides with the reference direction is defined as the dividing plane of the exhaust edge. The angle bisector direction of the reference direction and the direction of the camber line tangent to the exhaust edge at the wingtip section is defined as the feed direction of the tool cathode on the wingtip side of the exhaust edge. The angle bisector direction of the reference direction and the direction of the camber line tangent to the exhaust edge at the wing root section is defined as the feed direction of the tool cathode on the wing root side of the exhaust edge.

[0017] Furthermore, in the above-mentioned synchronous electrolytic machining method for segmenting the intake / exhaust edges of a wing with a large twist angle, after segmentation, the tip side of the intake edge and the root side of the intake edge are machined simultaneously, or the tip side of the exhaust / intake edge and the root side of the exhaust edge are machined simultaneously.

[0018] Furthermore, the embodiment of the present application provides an apparatus applicable to the segmented synchronous electrolytic machining method of the intake / exhaust edges of an air wing having a large twist angle, comprising a segmented synchronous feed mechanism, an air wing root side tool cathode, and an air wing tip side tool cathode, wherein the segmented synchronous feed mechanism consists of a spindle adapter block, an air wing root side wedge mechanism, and an air wing tip side wedge mechanism. The wing root wedge mechanism consists of a wing root guide rail base, a wing root cathode base, and a wing root guide rod. The wing root guide rail base is fixedly mounted to the machine tool platform, the wing root cathode base is attached to the wing root guide rail base via a corresponding guide rail slider, and the wing root guide rod is attached to an inclined groove in the wing root cathode base, forming a pair of wedge mechanisms. The end face of the wing root guide rod is attached to the spindle of the machine tool via a spindle adapter block, the wing root tool cathode is attached to a corresponding wing root cathode base, and the angle of the wing root wedge mechanism coincides with the feed direction of the wing root tool cathode at the intake edge or the feed direction of the wing root tool cathode at the exhaust edge. The wingtip wedge mechanism consists of a wingtip guide rail base, a wingtip cathode base, and a wingtip guide rod. The wingtip guide rail base is fixedly mounted to the machine tool platform, the wingtip cathode base is attached to the wingtip guide rail base via a corresponding guide rail slider, and the wingtip guide rod is attached to an inclined groove in the wingtip cathode base, forming a pair of wedge mechanisms. The end faces of the wingtip guide rods are attached to the spindle of the machine tool via a spindle adapter block, and the wingtip tool cathode is attached to a corresponding wingtip cathode base. The angle of the wingtip wedge mechanism coincides with the feed direction of the wingtip tool cathode on the intake edge or the feed direction of the wingtip tool cathode on the exhaust edge.

[0019] Furthermore, the embodiment of the present application provides a processing method for the intake / exhaust edges of a wing having a large twist angle using a segmented synchronous electrolytic device. Step 1 involves attaching the segmented synchronous feed mechanism to the machine tool, connecting the spindle adapter block to the spindle of the machine tool, and adjusting the position of the spindle of the machine tool to adjust the positions of the two segmented tool cathodes so that the two tool cathode surfaces form a complete and continuous cathode surface. Step 2 involves mounting the wing blank in a jig, measuring, positioning, and aligning the tools, and maintaining an initial machining gap between the wingtip tool cathode, the wing root tool cathode, and the wing blank. Step 3 involves connecting the blade blank to the positive terminal of the power supply, connecting the blade tip tool cathode and blade root tool cathode to the negative terminal of the power supply, using a counter-flow field of liquid supply from both sides for machining, dividing the electrolyte into four paths, flowing into the machining gap from the main liquid inlet on the blade tip side, the main liquid inlet on the blade root side, and the auxiliary liquid inlet, flowing along the intake edge / exhaust edge, and freely flowing out from the lower guide shell on the blade tip side, the lower guide shell on the blade root side, and the open outlet formed by the blade, During machining, the spindle of the machine tool pushes the wingtip-side guide rod and the wing root-side guide rod and feeds them simultaneously in the horizontal direction. The wedge mechanism formed by the wingtip-side guide rod and the wingtip-side cathode base converts the horizontal feed of the wingtip-side guide rod into a feed in the inclination angle direction of the wingtip-side cathode base and further drives the wingtip-side tool cathode to approach the intake edge / exhaust edge. The wedge mechanism formed by the wing root-side guide rod and the wing root-side cathode base converts the horizontal feed of the wing root-side guide rod into a feed in the inclination angle direction of the wing root-side cathode base and further drives the wing root-side tool cathode to approach the intake edge / exhaust edge. Step 4 achieves synchronous forming of the intake edge / exhaust edge through the synchronous motion and electrochemical dissolution of the wingtip-side tool cathode and the wing root-side tool cathode. This includes step 5, which involves turning off the power supply, the electrolyte circulation system, and the machine tool. [Effects of the Invention]

[0020] Compared to the prior art, the present invention has the following remarkable features.

[0021] (1) The embodiments of this application propose a method for electrolytically machining the intake edge / exhaust edge of a blade with a large twist angle in the tangential direction. The intake edge / exhaust edge of the blade with a large twist angle is divided into two sections along a certain determined cross-section, the twist angle of the intake edge / exhaust edge of each section is reduced, and then the intake edge / exhaust edge of the blades of the two sections are simultaneously electrolytically machined in the tangential direction. By such a segmented synchronous electrolytic machining method for the intake edge / exhaust edge of the blade, when machining the intake edge / exhaust edge of the blade with a large twist angle in the tangential direction, due to the overly large twist angle, the included angle between the feed direction and the tangential direction of the cross-sectional contour camber line becomes too large, and the problem that the size deviation of the machined intake edge / exhaust edge is too large is effectively solved.

[0022] (2) The embodiments of this application designed a segmented synchronous electrolytic machining device for the intake edge / exhaust edge of a blade with a large twist angle. By the linear motion of a single motion axis, the tool cathodes of the two intake edges / exhaust edges are directly driven to perform synchronous motion along a predetermined included angle direction, ensuring the synchronism and consistency of the feed of the two tool cathodes, and enabling the segmented synchronous machining of the intake edge / exhaust edge of the blade with a large twist angle to be completed relatively well.

[0023] (3) The method for electrolytically machining the intake edge / exhaust edge of a blade with a large twist angle disclosed in the embodiments of this application has a wide application range and high machining flexibility. For members such as the intake edge / exhaust edge of an integral blisk blade and the intake edge / exhaust edge of a diffuser blade, the tool cathode for the intake edge / exhaust edge can be specifically designed for machining.

Brief Description of the Drawings

[0024] [Figure 1] It is a schematic diagram of a segmented synchronous feed electrolytic machining device. [Figure 2] It is a partial cross-sectional view of a segmented synchronous feed electrolytic machining device. [Figure 3] It is a schematic diagram of the cathode for the segmented synchronous feed of the intake edge / exhaust edge. [Figure 4] This is a schematic diagram of the dividing surface of the intake edge / exhaust edge of the wing. [Figure 5] This is a schematic diagram showing the tangent lines to the camber lines in each cross-section and the feed direction. [Figure 6] This is a schematic diagram of the cathode feed direction for each segmented synchronous feed process. [Modes for carrying out the invention]

[0025] The technical solutions of the present invention will be further described below with reference to the drawings.

[0026] As shown in Figures 1 and 2, the segmented synchronous feed mechanism includes a wing root wedge mechanism, a wing tip wedge mechanism, and a spindle adapter block 6. The two wedge mechanisms mainly include a wing tip guide rod 7 and a wing root guide rod 4 having opposite inclination angles, a wing tip cathode base 8 and a wing root cathode base 3 with inclined grooves corresponding to the inclination angles of the guide rods, two pairs of guide rail sliders 2 (only one pair is shown in the figures), and a wing tip guide rail base 5 and a wing root guide rail base 1 having opposite end face inclination angles. When installing, guide rail bases 1 and 5 are fixed to the machine tool platform, cathode bases 3 and 8 are attached to guide rail bases 1 and 5 via guide rail sliders, respectively, the wing root guide rod 4 and the wing tip guide rod 7 are attached to the inclined grooves of the wing root cathode base 3 and the wing tip cathode base 8, respectively, forming a wedge mechanism, and the bottoms of the wing root guide rod 4 and the wing tip guide rod 7 are attached to the spindle of the machine tool via the spindle adapter block 6. The intake edge / exhaust edge tool cathode includes the intake edge / exhaust edge tool cathode 15 and the intake edge / exhaust edge tool cathode 16, and each tool cathode includes several parts such as the tool cathode body, cathode insulating block, upper guide shell with main liquid inlet, and lower guide shell with auxiliary liquid inlet. The upper and lower guide shells and cathode insulating block are directly attached to the tool cathode body and do not need to be frequently attached and detached during machining. The wing root intake / exhaust edge tool cathode 15 and the wing tip intake / exhaust edge tool cathode 16 are attached to the wing root cathode base 3 and the wing tip cathode base 8, respectively, forming a complete segmented synchronous electrolytic machining apparatus.During machining, the spindle of the machine tool simultaneously pushes the wing root guide rod 4 and the wing tip guide rod 7 to feed horizontally. The pair of wedge mechanisms formed by the wing root guide rod 4 and the wing tip guide rod 7 with the wing root cathode base 3 and the wing tip cathode base 8 respectively convert the horizontal feed of the guide rods into feed in the direction of the inclination angle of the respective guide rail bases of the wing root cathode base 3 and the wing tip cathode base 8. Furthermore, it drives the wing root intake edge / exhaust edge tool cathode 15 and the wing tip intake edge / exhaust edge tool cathode 16 to feed the intake edge / exhaust edge synchronously. During processing, the flow field uses opposing flow fields with liquid supplied from both sides, dividing the electrolyte into four paths. These paths flow into the processing gap from the main liquid inlet and auxiliary liquid inlet of the upper guide shell 10 on the blade root side and the upper guide shell 9 on the blade tip side, respectively. The electrolyte flows along the intake / exhaust edges of the blank of the blade 12 and freely flows out from the open outlets formed by the lower guide shell 13 on the blade root side, the lower guide shell 11 on the blade tip side, and the blade 14.

[0027] As shown in Figures 4 and 5, the method for determining the feeding direction of the intake edge / exhaust edge tool cathode and the division cross-section of the intake edge / exhaust edge of the blade is as follows: Step S1 involves cutting out the wingtip cross-sectional contour line 17 and the wing root cross-sectional contour line 20 from a three-dimensional model of the wing and projecting them onto the same plane, drawing several inscribed circles on each of the two cross-sectional contours, and fitting the centers of all the inscribed circles to the camber line. Step S2 involves drawing a tangent line to the camber line at the intersection of the camber line and the intake / exhaust edge, extending outward from the cross-sectional contour, and using the direction of the angle bisector of the tangent line to the camber line between the wingtip and wing root sections as the reference direction. Step S3 includes setting an airfoil cross section where the tangential direction of the camber line coincides with the reference direction as the dividing surface 18 of the intake edge / exhaust edge, setting the angle bisector direction of the reference direction and the direction tangential to the camber line of the tip cross section contour as the feed direction 1 of the tip-side tool cathode 16 of the intake edge / exhaust edge, and setting the angle bisector direction of the reference direction and the tangential direction of the camber line of the tip cross section contour as the feed direction 2 of the tip-side tool cathode 15 of the intake edge / exhaust edge.

[0028] As shown in Figures 1 and 6, when using the segmented synchronous electrolytic machining method for intake / exhaust edges of blades with a large twist angle according to the present invention, Step 1 involves attaching the segmented synchronous feed mechanism to the machine tool, connecting the spindle adapter block 6 to the spindle of the machine tool, and adjusting the position of the spindle of the machine tool to adjust the positions of the two segmented tool cathodes so that the two tool cathode surfaces form a complete and continuous cathode surface. Step 2 involves mounting the blank of the wing 12 to a jig, measuring, positioning, and aligning the tools, and maintaining an initial machining gap between the wingtip side tool cathode 16, the wing root side tool cathode 15, and the blank of the wing 12. Step 3 involves connecting the blank of the blade 12 to the positive terminal of the power supply, connecting the blade tip side tool cathode 16 and the blade root side tool cathode 15 to the negative terminal of the power supply, using a counter-flow field of liquid supply from both sides for machining, dividing the electrolyte into four paths, flowing into the machining gap from the main liquid inlet on the blade tip side, the main liquid inlet on the blade root side, and the auxiliary liquid inlet, respectively, flowing along the intake edge / exhaust edge, and freely flowing out from the lower guide shell 11 on the blade tip side, the lower guide shell 12 on the blade root side, and the open outlet formed by the blade, During machining, the spindle of the machine tool pushes the tip-side guide rod 7 and the root-side guide rod 4 and feeds them simultaneously in the horizontal direction. The wedge mechanism formed by the tip-side guide rod 7 and the tip-side cathode base 8 converts the horizontal feed of the tip-side guide rod 7 into a feed in the inclination angle direction of the tip-side guide rail base 5 of the tip-side cathode base 8, and further drives the tip-side tool cathode 16 to approach the intake edge / exhaust edge. The wedge mechanism formed by the root-side guide rod 4 and the root-side cathode base 3 converts the horizontal feed of the root-side guide rod 4 into a feed in the inclination angle direction of the root-side guide rail base 1 of the root-side cathode base 3, and further drives the root-side tool cathode 15 to approach the intake edge / exhaust edge. Through the synchronous motion and electrochemical dissolution of the tip-side tool cathode 16 and the root-side tool cathode 15, synchronous forming of the intake edge / exhaust edge is achieved in step 4. This includes step 5, which involves turning off the power supply, the electrolyte circulation system, and the machine tool. [Explanation of symbols]

[0029] 1. Guide rail base at the wing root. 2. Guide rail slider 3. Cathode base at the wing root 4. Guide rod at the wing root 5. Wingtip side guide rail base 6. Spindle adapter block 7. Wingtip guide rod 8. Wingtip side cathode base 9. Guide shell above the cathode on the wingtip side 10. Guide shell above the cathode on the wing root side 11. Guide shell under the wingtip cathode 12, wings 13. Guide shell at the lower cathode of the wing root. 14. Cathode isolation block 15. Tool cathode at the wing root. 16, Blade tip side tool cathode 17. Wingtip cross-sectional contour line 18. Segmented synchronous machining dividing surface 19. Cross-sectional contour of the divided surface 20. Wing root cross-sectional contour line

Claims

1. A segmentation synchronous electrolytic machining method for the intake / exhaust edges of an air wing with a large twist angle, For wing blades with a large twist angle, segmentation synchronous machining is performed, and the method for determining the segmented cross-section and the feed direction of the tool cathode after segmentation are determined by the following method: Step 1. Cut out the wingtip cross-sectional contour line (17) and the wing root cross-sectional contour line (20) from the three-dimensional model of the wing and project them onto the same plane. Step 2. Draw several inscribed circles on the projected contours of the wingtip section contour line (17) and the wing root section contour line (20), and fit them to the camber lines passing through the centers of the inscribed circles to form the wingtip section camber lines and the wing root section camber lines, respectively. Step 3. Draw a tangent line to the camber line at the intersection of the wingtip section camber line and the intake edge, extending outwards from the cross-sectional contour, and call this the wingtip section camber line intake edge tangent. Draw a tangent line to the camber line at the intersection of the wing root section camber line and the intake edge, extending outwards from the cross-sectional contour, and call this the wing root section camber line intake edge tangent. Draw a tangent line to the camber line at the intersection of the wingtip section camber line and the exhaust edge, extending outwards from the cross-sectional contour, and call this the wingtip section camber line exhaust edge tangent. Draw a tangent line to the camber line at the intersection of the wing root section camber line and the exhaust edge, extending outwards from the cross-sectional contour, and call this the wing root section camber line exhaust edge tangent. Step 4. The angle bisector direction of the tangent line between the camber line and intake edge at the wingtip section and the camber line and intake edge at the wing root section is defined as the reference direction, and the airfoil section where the camber line tangent direction coincides with the reference direction is defined as the dividing surface of the intake edge, the angle bisector direction of the tangent line between the reference direction and the camber line and intake edge at the wingtip section is defined as the feed direction of the tool cathode on the wingtip side of the intake edge, and the angle bisector direction of the tangent line between the reference direction and the camber line and intake edge at the wing root section is defined as the feed direction of the tool cathode on the wing root side of the intake edge. A method characterized by defining the angle bisector direction of the camber line tangent to the exhaust edge at the wingtip section and the camber line tangent to the exhaust edge at the wing root section as the reference direction, defining the airfoil section where the camber line tangent direction coincides with the reference direction as the dividing surface of the exhaust edge, defining the angle bisector direction of the camber line tangent to the exhaust edge at the wingtip section as the feed direction of the tool cathode on the wingtip side of the exhaust edge at the reference direction and defining the angle bisector direction of the camber line tangent to the exhaust edge at the wing root section as the feed direction of the tool cathode on the wing root side of the exhaust edge at the wing root side as the feed direction of the tool cathode on the wing root side of the exhaust edge at the wing root section as the reference direction.

2. A synchronous electrolytic segmentation method for the intake / exhaust edges of an airfoil with a large twist angle, as described in claim 1, characterized in that, after segmentation, the tip side of the intake edge and the root side of the intake edge are processed simultaneously, or the tip side of the exhaust edge and the root side of the exhaust edge are processed simultaneously.

3. An apparatus for realizing a segmented synchronous electrolytic machining method for the intake / exhaust edges of an air wing having a large twist angle as described in claim 2, comprising a segmented synchronous feed mechanism, an air wing root side tool cathode (15), and an air wing tip side tool cathode (16), wherein the segmented synchronous feed mechanism is composed of a spindle adapter block (6), an air wing root side wedge mechanism, and an air wing tip side wedge mechanism, The wing root wedge mechanism consists of a wing root guide rail base (1), a wing root cathode base (3), and a wing root guide rod (4). The wing root guide rail base (1) is fixedly mounted to the platform of the machine tool, the wing root cathode base (3) is attached to the wing root guide rail base (1) via a corresponding guide rail slider, and the wing root guide rod (4) is attached to an inclined groove in the wing root cathode base (3), forming a pair of wedge mechanisms. The end face of the wing root guide rod (4) is attached to the spindle of the machine tool via a spindle adapter block (6), and the wing root tool cathode (15) is attached to the corresponding wing root cathode base (3). The angle of the wing root wedge mechanism coincides with the feed direction of the wing root tool cathode at the intake edge or the feed direction of the wing root tool cathode at the exhaust edge. The wingtip wedge mechanism is comprised of a wingtip guide rail base (5), a wingtip cathode base (8), and a wingtip guide rod (7), wherein the wingtip guide rail base (5) is fixedly mounted to the platform of the machine tool, the wingtip cathode base (8) is attached to the wingtip guide rail base (5) via a corresponding guide rail slider, and the wingtip guide rod (7) is attached to an inclined groove of the wingtip cathode base (8), forming a pair of wedge mechanisms, the end face of the wingtip guide rod (7) is attached to the spindle of the machine tool via a spindle adapter block (6), the wingtip tool cathode (16) is attached to the corresponding wingtip cathode base (8), and the angle of the wingtip wedge mechanism is characterized in that it coincides with the feeding direction of the wingtip tool cathode of the intake edge or the feeding direction of the wingtip tool cathode of the exhaust edge.

4. A processing method for the intake / exhaust edge of an airfoil having a large twist angle as described in claim 3, using a segmentation synchronous electrolytic apparatus, Step 1 involves attaching the segmented synchronous feed mechanism to the machine tool, connecting the spindle adapter block (6) to the spindle of the machine tool, and adjusting the position of the spindle of the machine tool to adjust the positions of the two segmented tool cathodes so that the two tool cathode surfaces form a complete and continuous cathode surface. Step 2 involves attaching the blank of the wing (12) to a jig, measuring, positioning, and aligning the tools, and maintaining an initial machining gap between the wingtip side tool cathode (16), the wing root side tool cathode (15), and the blank of the wing (12). Step 3 involves connecting the blank of the blade (12) to the positive terminal of the power supply, connecting the blade tip tool cathode (16) and the blade root tool cathode (15) to the negative terminal of the power supply, using a counter-flow field of liquid supply from both sides for the machining flow field, dividing the electrolyte into four paths, flowing into the machining gap from the main liquid inlet on the blade tip side, the main liquid inlet on the blade root side, and the auxiliary liquid inlet, flowing along the intake edge / exhaust edge, and freely flowing out from the lower guide shell (11) on the blade tip side, the lower guide shell (12) on the blade root side, and the open outlet formed by the blade, During machining, the spindle of the machine tool pushes the wingtip guide rod (7) and the wing root guide rod (4) simultaneously in the horizontal direction, and the wedge mechanism formed by the wingtip guide rod (7) and the wingtip cathode base (8) converts the horizontal movement of the wingtip guide rod (7) into movement of the wingtip cathode base (8) in the direction of the inclination angle of the wingtip guide rail base (5), and further drives the wingtip tool cathode (16) to approach the intake edge / exhaust edge, and the wing root guide rod Step 4 involves the wedge mechanism formed by the guide rod (4) and the root-side cathode base (3) converting the horizontal feed of the root-side guide rod (4) into a feed of the root-side cathode base (3) in the inclination angle direction of the root-side guide rail base (1), and further driving the root-side tool cathode (15) to approach the intake edge / exhaust edge, thereby achieving synchronous molding of the intake edge / exhaust edge through the synchronous motion and electrochemical dissolution of the tip-side tool cathode (16) and the root-side tool cathode (15), A machining method characterized by including step 5 of turning off the power supply, the electrolyte circulation system, and the machine tool.

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