A magnetic support system for electrolytic machining of large-size thin-walled curved surface parts

Abstract

The application belongs to the field of fixture mechanism of electrolytic machining, in particular to a magnetic support system for electrolytic machining of large-size thin-walled curved surface parts, comprising: a numerical control coil magnetic field generating system arranged around the machining area for generating and adjusting the magnetic field; a discrete magnet support system arranged at the bottom of the workpiece and fixedly connected with the workpiece for providing support force for the workpiece and compensating the deformation of the workpiece; a mechanical positioning system located below the workpiece for placing the workpiece and positioning the workpiece; a surface shape test feedback system for real-time measurement of the surface shape of the workpiece by line laser for monitoring the deformation of the workpiece and providing control feedback for the adjustment of the magnetic field; the surface shape test feedback system is used for fitting the actual surface shape data of the workpiece in the machining area into the surface shape of the workpiece and comparing with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece. The application can compensate the deformation of the large-size thin-walled curved surface part caused by gravity and clamping force in real time and correct the surface shape in time.

Description

Technical Field

[0001] This invention belongs to the field of clamping mechanisms for electrolytic machining, specifically a magnetic support system for electrolytic machining of large-sized thin-walled curved parts. Background Technology

[0002] Large-sized thin-walled curved surface parts are widely used in core components of aerospace vehicles such as aircraft skins and rocket box bottoms. With the continuous development of the aerospace industry, the iterative upgrades in aircraft performance require further increases in the diameter-to-thickness ratio of these large-sized thin-walled curved surface parts. These parts are characterized by complex shapes and low rigidity, making them prone to deformation during machining, resulting in difficulty in ensuring machining accuracy and poor surface quality.

[0003] Electrolytic machining (EMC) is a method of machining workpieces using an electrolyte solution. During the process, no mechanical or thermal stress is generated on the parts, thus preventing deformation of weak or rigid components and improving machining accuracy and quality. EMC also offers many advantages, such as relatively low requirements for workpiece materials, making it suitable for machining various metals; precise control of the machining process within the electrolyte according to the workpiece's design requirements, enabling the machining of complex curved surfaces; and high machining efficiency, allowing for rapid machining of large, thin-walled curved parts through optimized process parameters. Therefore, EMC is highly suitable for machining large, thin-walled curved parts.

[0004] Currently, large-sized thin-walled curved parts are typically fixed using traditional mechanical clamping methods or multi-point flexible support methods. Traditional mechanical clamping is the most common clamping method, but it has disadvantages: 1) It generates significant clamping stress on the workpiece during the clamping process, causing clamping deformation; 2) It cannot compensate for the deformation of large-sized thin-walled curved parts due to their own weight. To address the deformation problem during the machining of large-sized thin-walled curved parts, researchers have developed a multi-point flexible support method, which has shown significant improvement. However, it also has drawbacks: 1) High cost: A complete multi-point flexible support system requires dozens or even hundreds of support units. Each support unit is equipped with an independent electrical control, pneumatic, hydraulic, and mechanical motion system. The main structure of the support unit also needs to possess physical properties such as lightweight, high temperature resistance, flame retardancy, and thermosetting properties, as well as protective and precision control adjustment functions, which greatly increases the design and manufacturing cost of the multi-point flexible support system; 2) Poor reliability: During electrolytic machining, a large amount of electrolyte is present in the machining area. The electrohydraulic system of the support unit is immersed in the electrolyte for a long time, which can easily lead to corrosion, leakage, and other problems, causing the entire system to fail. In severe cases, it can cause harm to the machine tool and operators.

[0005] Therefore, existing clamping methods cannot meet the processing requirements of high precision, low deformation, high reliability, and low cost in the electrolytic machining of large-sized thin-walled curved parts. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a magnetic support system for electrolytic machining of large-sized thin-walled curved parts. The system utilizes the force of a magnet in a non-uniform magnetic field to support the weakly rigid large-sized thin-walled curved parts. The magnitude and direction of the force can be adjusted by changing the strength and distribution of the magnetic field, thereby correcting the surface shape of the large-sized thin-walled curved parts.

[0007] The technical solution adopted by the present invention to achieve the above objectives is: a magnetic support system for electrolytic machining of large-size thin-walled curved parts, comprising: a CNC coil magnetic field generating system, a discrete magnet support system, a mechanical positioning system, and a surface shape testing feedback system;

[0008] The CNC coil magnetic field generating system is located around the machining area and on the system frame. The system frame contains conductive coils for generating and adjusting the magnetic field.

[0009] The discrete magnet support system is located at the bottom of the workpiece and is fixedly connected to the workpiece. It is used to provide support force for the workpiece and compensate for workpiece deformation.

[0010] The mechanical positioning system is located below the workpiece and is used to place and position the workpiece.

[0011] The surface shape testing feedback system is located above the workpiece and measures the surface shape of the workpiece in real time using a line laser to monitor the deformation of the workpiece and provide control feedback for magnetic field adjustment.

[0012] The surface shape testing feedback system is used to fit the actual surface shape data of the workpiece in the measurement processing area to the workpiece surface shape, and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece.

[0013] The numerically controlled coil magnetic field generating system includes: a three-dimensional coil, a power supply, a gaussmeter, and a magnetic field control unit;

[0014] Among them, the three-dimensional coil is set on the system frame, and the magnetic field it generates covers the CNC coil magnetic field generating system, the discrete magnet support system, and the mechanical positioning system, which are used to generate a spatial magnetic field in the processing area.

[0015] The power supply is connected to the three-dimensional coil to provide power to the three-dimensional coil;

[0016] A gaussmeter is placed on the worktable below the workpiece to measure the magnetic field generated by the coil for control purposes and to feed back to the magnetic field control unit.

[0017] The magnetic field control unit is used to calculate and control the magnetic field strength. The three-dimensional coil and the power supply form a current loop. A variable resistor is provided in the loop. By controlling the resistance value of the variable resistor, the magnetic field strength generated by each coil is controlled. The magnetic fields generated by the three-dimensional coil are superimposed to obtain an arbitrarily distributed spatial magnetic field.

[0018] The three-dimensional coil includes: an x-direction coil, a y-direction coil, and a z-direction coil;

[0019] The x-direction coil and y-direction coil are both located on the top and bottom surfaces of the system frame in the x and y directions, respectively; the z-direction coil is located on both sides of the system frame.

[0020] Each group of coils in the same direction has the same number of turns and is parallel to each other. At the same time, each group of coils is located on both sides of the processing area to generate a spatial magnetic field within the processing area.

[0021] Each of the x-direction coil, y-direction coil, and z-direction coil forms an independent current loop with the power supply.

[0022] The discrete magnet support system includes: a plurality of discrete magnet blocks disposed on the bottom surface of the workpiece, which are used to convert the magnetic force received in the magnetic field into a supporting force acting on the workpiece;

[0023] The discrete magnet blocks are arranged in a single row on the bottom surface of the workpiece, with adjacent discrete magnet blocks spaced at the same interval, and the shape of each discrete magnet block is adapted to the two edges of the bottom surface of the workpiece.

[0024] The mechanical positioning system includes: a worktable and a positioning rod disposed on the worktable;

[0025] The worktable is used to place the workpiece; there are multiple positioning rods, all of which are vertically arranged on the worktable, and the sidewalls of the positioning rods are attached to the edge of the workpiece and tangent to the workpiece.

[0026] The positioning rod is fitted with a positioning ring to constrain movement in three degrees of freedom: x-axis, y-axis, and z-axis.

[0027] The surface shape testing feedback system includes: a laser sensor, a guide rail, and a main control computer;

[0028] There are two guide rails, which are horizontally fixed between two longitudinal beams on the same plane of the system frame.

[0029] A slider is slidably disposed between two guide rails; a linear motion mechanism is disposed on the bottom surface of the slider, and the laser sensor is vertically disposed on the linear motion mechanism, with the field of view of the laser sensor facing vertically downward. During the horizontal displacement of the guide rails, the slider drives the laser sensor to perform linear scanning and lateral translation along the x-axis or y-axis. During the movement, the laser sensor scans downward and measures the actual surface shape data of the workpiece in the processing area based on the emitted laser and the reflected signal of the received laser.

[0030] The computer is used to receive the reflected signal sent by the laser sensor, fit it into the surface shape of the workpiece, and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece.

[0031] The laser sensor is a line laser sensor.

[0032] A method of using a magnetic support system for electrolytic machining of large-sized thin-walled curved parts includes the following steps:

[0033] 1) The workpiece is placed on the worktable and positioned by the positioning rod on the worktable;

[0034] 2) Turn on the power of the CNC coil magnetic field generating system. The x-direction coil, y-direction coil and z-direction coil are energized to generate magnetic fields. The magnetic field distribution and intensity generated by the coil are controlled by the magnetic field control unit. The magnetic fields generated by the x-direction coil, y-direction coil and z-direction coil can be superimposed to generate a spatial magnetic field with arbitrary distribution within the processing area. The generated spatial magnetic field is detected by a gaussmeter and fed back to the magnetic field control unit so that the computer can accurately control the magnetic field.

[0035] 3) The discrete magnet support system converts the magnetic force received in the spatial magnetic field of the processing area into a supporting force that acts on the workpiece to compensate for the deformation of the workpiece.

[0036] 4) The laser sensor detects the deformation of the workpiece. The guide rail drives the laser sensor to complete the full-surface scanning of the workpiece and feeds back the actual surface shape data of the workpiece in the measurement and processing area to the surface shape test feedback main control computer.

[0037] 5) The main control computer fits the workpiece surface shape based on the actual surface shape data of the workpiece in the measurement and processing area, and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece.

[0038] 6) The main control computer adjusts the variable resistance of the loop in the three-dimensional coil to control the current through the workpiece based on the workpiece deformation feedback from the line laser sensor, thereby adjusting the spatial magnetic field strength in the processing area to achieve closed-loop control.

[0039] Step 3) specifically includes:

[0040] (1) The potential energy of a discrete magnet block in a magnetic field is expressed as: U = -m·B;

[0041] Where m is the magnetic moment and B is the magnetic flux density;

[0042] (2) The force on the discrete magnet block in the magnetic field is:

[0043] Where U is the potential energy of the discrete magnet block in the magnetic field;

[0044] This allows us to obtain the supporting force experienced by the discrete magnet block in the magnetic field.

[0045] The main control computer fits the workpiece surface shape based on the actual surface shape data of the workpiece in the measurement and processing area, and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece, including the following steps:

[0046] (1) The slider on the guide rail drives the laser sensor to perform fixed-step scanning according to the planned path, and ensures that the entire surface of the workpiece is scanned;

[0047] (2) Record the height signal of the workpiece surface received by the laser sensor and the spatial coordinates of the laser sensor for each measurement;

[0048] (3) Use the workpiece height signal and sensor spatial coordinates to splice together the height matrix of the complete surface of the workpiece, and further use polynomial or other non-spherical characterization functions to fit and form the workpiece surface shape function;

[0049] (4) The workpiece surface shape function is subtracted from the workpiece theoretical surface shape function to obtain the workpiece deformation function, which is the amount of workpiece deformation.

[0050] The present invention has the following beneficial effects and advantages:

[0051] 1. This invention can avoid clamping stress during the process of holding and clamping the workpiece, and effectively reduce the clamping deformation of thin-walled curved parts;

[0052] 2. This invention can compensate for the deformation of large-sized thin-walled curved parts caused by gravity and clamping force in real time, and correct the surface shape in a timely manner;

[0053] 3. This invention has only a small amount of mechanical structure in the processing area, no electro-hydraulic system that is prone to failure, and the main components do not come into contact with the electrolyte, which can ensure the high reliability of the system. It also has a simple structure and low cost. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the magnetic support system for electrolytic machining of large-size thin-walled curved parts according to the present invention;

[0055] Figure 2This is a schematic diagram of the discrete magnet support system of the present invention;

[0056] Among them, 1 is the x-direction coil, 2 is the y-direction coil, 3 is the z-direction coil, 4 is the gaussmeter, 5 is the worktable, 6 is the workpiece, 7 is the positioning rod, 8 is the line laser sensor, 9 is the guide rail, 10 is the discrete magnet block, and 11 is the processing area. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0058] like Figure 1 The diagram shown is a structural schematic of the present invention. The present invention provides a magnetic support system for electrolytic machining of large-size thin-walled curved surface parts, characterized in that it includes: a CNC coil magnetic field generating system, a discrete magnet support system, a mechanical positioning system, and a surface shape testing feedback system.

[0059] The CNC coil magnetic field generating system is located around the machining area and on the system frame. The system frame contains conductive coils for generating and adjusting the magnetic field.

[0060] The discrete magnet support system is located at the bottom of the workpiece 6 and is fixedly connected to the workpiece 6. It is used to provide support force for the workpiece 6 and compensate for the deformation of the workpiece 6.

[0061] The mechanical positioning system is located below workpiece 6 and is used to place and position the workpiece.

[0062] The surface shape testing feedback system is located above workpiece 6. It measures the surface shape of the workpiece in real time using a line laser to monitor the deformation of workpiece 6 and provide control feedback for magnetic field adjustment.

[0063] The surface shape test feedback system is used to fit the surface shape of the workpiece 6 based on the actual surface shape data of the workpiece 6 in the measurement processing area 11, and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece 6.

[0064] In the structure of this invention, the numerically controlled coil magnetic field generating system includes: a three-dimensional coil, a power supply, a gaussmeter, and a magnetic field control unit;

[0065] Among them, the three-dimensional coil is set on the system frame, and the magnetic field formed is covered by the CNC coil magnetic field generating system, the discrete magnet support system, and the mechanical positioning system, which are used to generate a spatial magnetic field in the processing area 11.

[0066] The power supply is connected to the three-dimensional coil to provide power to the three-dimensional coil;

[0067] A gaussmeter 4 is placed on the worktable 5 below the workpiece 6 to measure the magnetic field generated by the coil for control and to feed it back to the magnetic field control unit.

[0068] The magnetic field control unit is used to calculate and control the magnetic field strength. The three-dimensional coil and the power supply form a current loop. A variable resistor is provided in the loop. By controlling the resistance value of the variable resistor, the magnetic field strength generated by each coil is controlled. The magnetic fields generated by the three-dimensional coil are superimposed to obtain an arbitrarily distributed spatial magnetic field.

[0069] The three-dimensional coil includes: coil 1 in the x-direction, coil 2 in the y-direction, and coil 3 in the z-direction;

[0070] The x-direction coil 1 and y-direction coil 2 are both located on the top and bottom surfaces of the system frame in the x and y directions, respectively; the z-direction coil 3 is located on both sides of the system frame.

[0071] Each group of coils in the same direction has the same number of turns and is parallel to each other. At the same time, each group of coils is located on both sides of the processing area 11 to generate a spatial magnetic field within the processing area 11.

[0072] Each of the x-direction coil 1, y-direction coil 2, and z-direction coil 3 forms an independent current loop with the power supply.

[0073] like Figure 2 The diagram shown is a schematic diagram of the discrete magnet support system of the present invention. In this embodiment, the discrete magnet support system includes: a plurality of discrete magnet blocks 10 disposed on the bottom surface of the workpiece 6, which are used to convert the magnetic force received in the magnetic field into a supporting force and apply it to the workpiece 6.

[0074] Discrete magnet blocks 10 are arranged in a single row on the bottom surface of workpiece 6, with adjacent discrete magnet blocks 10 having the same spacing, and the shape of each discrete magnet block 10 is adapted to the two edges of the bottom surface of workpiece 6.

[0075] like Figure 1 As shown, the mechanical positioning system includes: a worktable 5 and a positioning rod 7 disposed on the worktable 5;

[0076] The workbench 5 is used to place the workpiece 6; there are multiple positioning rods 7, all of which are vertically arranged on the workbench 5, and the sidewalls of the positioning rods are attached to the edge of the workpiece 6 and are tangent to the workpiece 6.

[0077] A positioning ring is fitted on the positioning rod 7 to constrain the movement in three degrees of freedom, including the x-direction, y-direction, and z-axis.

[0078] The surface shape testing feedback system includes: a laser sensor 8, a guide rail 9, and a main control computer;

[0079] In this embodiment, there are two guide rails 9, which are horizontally fixed between two longitudinal beams on the same plane of the system frame.

[0080] A slider is slidably disposed between the two guide rails 9; a linear motion mechanism is disposed on the bottom surface of the slider; the laser sensor 8 is a line laser sensor, which is vertically disposed on the linear motion mechanism, and the field of view of the laser sensor 8 is vertically downward; during the horizontal displacement of the guide rail 9, the slider drives the laser sensor 8 to perform linear scanning and lateral translation along the x-axis or y-axis; during the movement, the laser sensor 8 scans downward; and measures the actual surface shape data of the workpiece 6 in the processing area 11 based on the emitted line laser and the received line laser reflection signal.

[0081] The computer is used to receive the reflected signal sent by the laser sensor 8, fit it into the surface shape of the workpiece, and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece 6.

[0082] like Figure 1 As shown in the schematic diagram of the present invention, the method of using a magnetic support system for electrolytic machining of large-size thin-walled curved parts includes the following steps:

[0083] 1) The workpiece 6 is placed on the worktable 5 and positioned by the positioning rod 7 on the worktable 5;

[0084] 2) Turn on the power to the CNC coil magnetic field generating system. The x-direction coil 1, y-direction coil 2, and z-direction coil 3 are energized to generate a magnetic field. The magnetic field distribution and intensity generated by the coils are controlled by the magnetic field control unit. The magnetic fields generated by the x-direction coil 1, y-direction coil 2, and z-direction coil 3 can be superimposed to generate a spatial magnetic field with arbitrary distribution within the processing area 11. The generated spatial magnetic field is detected by the gaussmeter 4 and fed back to the magnetic field control unit so that the computer can accurately control the magnetic field.

[0085] 3) The discrete magnet support system converts the magnetic force received in the processing area 11 into a supporting force that acts on the workpiece 6 to compensate for the deformation of the workpiece 6.

[0086] Specifically, the discrete magnet support system converts the magnetic force received in the processing area 11 into a supporting force that acts on the workpiece 6 within the spatial magnetic field.

[0087] (1) The potential energy of the discrete magnet block (10) in the magnetic field is expressed as: U = -m·B;

[0088] Where m is the magnetic moment and B is the magnetic flux density;

[0089] (2) The force on the discrete magnet block (10) in the magnetic field is:

[0090] Where U is the potential energy of the discrete magnet block in the magnetic field;

[0091] In turn, the supporting force of the discrete magnet block (10) in the magnetic field is obtained.

[0092] 4) The laser sensor 8 detects the deformation of the workpiece 6. The guide rail 9 drives the laser sensor 8 to complete the full-surface scanning of the workpiece 6, and feeds back the actual surface shape data of the workpiece 6 in the measurement processing area 11 to the surface shape test feedback main control computer.

[0093] 5) The main control computer fits the workpiece surface shape based on the actual surface shape data of the workpiece 6 in the measurement and processing area 11, and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece 6.

[0094] The main control computer fits the workpiece surface shape based on the actual surface shape data of the workpiece (6) in the measurement and processing area (11), and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece (6), including the following steps:

[0095] (1) The slider on the guide rail (9) drives the laser sensor (8) to perform fixed-step scanning according to the planned path, and ensures that the entire surface of the workpiece is scanned;

[0096] (2) Record the height signal of the workpiece surface received by the laser sensor (8) and the spatial coordinates of the laser sensor (8) each time;

[0097] (3) Use the workpiece height signal and sensor spatial coordinates to splice together the height matrix of the complete surface of the workpiece, and further use polynomial or other non-spherical characterization functions to fit and form the workpiece surface shape function;

[0098] (4) The workpiece surface shape function is subtracted from the workpiece theoretical surface shape function to obtain the workpiece deformation function, which is the amount of workpiece deformation.

[0099] 6) The main control computer adjusts the variable resistance of the loop in the three-dimensional coil to control the current through the workpiece based on the workpiece deformation feedback from the line laser sensor 8, thereby adjusting the spatial magnetic field strength in the processing area 11 to achieve closed-loop control.

[0100] Example 1:

[0101] Workpiece 6 is placed on workbench 5, and is positioned by workbench 5 and positioning rod 7. Above workbench 5 is processing area 11. Three-dimensional coils are arranged around processing area 11, consisting of x-direction coil 1, y-direction coil 2, and z-direction coil 3. Each direction has two parallel coils with the same number of turns, placed on either side of processing area 11. Each coil can be controlled by a computer to control the current flowing through it, thereby controlling the distribution and intensity of the magnetic field. The superposition of the magnetic fields generated by x-direction coil 1, y-direction coil 2, and z-direction coil 3 can generate an arbitrarily distributed spatial magnetic field within processing area 11. The generated spatial magnetic field is detected and fed back by gaussmeter 4, facilitating precise computer control of the magnetic field. Figure 2 As shown, the discrete magnet support system consists of discrete magnet blocks 10, which are multiple magnet blocks bonded to the bottom of the workpiece 6. The discrete magnet blocks 10 experience a force of [missing information] in the spatial magnetic field. Where U is the potential energy of the magnet in the magnetic field, the potential energy can be expressed as: Where m is the magnetic moment and B is the magnetic induction intensity, the discrete magnet block 10 converts the magnetic force it receives into a supporting force that acts on the workpiece 6 to compensate for the deformation of the workpiece 6; the deformation of the workpiece 6 is detected by the line laser sensor 8, which is fixed on the guide rail 9 and driven by the guide rail 9 to complete the full-surface scanning of the workpiece 6; the computer further adjusts the current through the coil based on the workpiece deformation feedback from the line laser sensor 8, thereby adjusting the spatial magnetic field intensity in the processing area 11 to achieve closed-loop control.

[0102] The above description is merely a specific example of the present invention and does not constitute any limitation on the present invention. Obviously, those skilled in the art, after understanding the content and principles of the present invention, may make various modifications and changes in form and details without departing from the principles and structure of the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A magnetic support system for electrolytic machining of large-sized thin-walled curved surface parts, characterized in that, include: Numerical control coil magnetic field generation system, discrete magnet support system, mechanical positioning system, surface shape testing feedback system; The CNC coil magnetic field generating system is located around the machining area and on the system frame. The system frame contains conductive coils for generating and adjusting the magnetic field. The numerically controlled coil magnetic field generating system includes: a three-dimensional coil, a power supply, a gaussmeter (4), and a magnetic field control unit; Among them, the three-dimensional coil is set on the system frame, and the magnetic field formed is covered by the CNC coil magnetic field generating system, the discrete magnet support system, and the mechanical positioning system, which are used to generate a spatial magnetic field in the processing area (11); The power supply is connected to the three-dimensional coil to provide power to the three-dimensional coil; A gaussmeter (4) is placed on a worktable (5) below the workpiece (6) to measure the magnetic field generated by the coil as a control signal and feed it back to the magnetic field control unit. The magnetic field control unit is used to calculate and control the magnetic field strength. The three-dimensional coil and the power supply form a current loop. A variable resistor is provided in the loop. By controlling the resistance value of the variable resistor, the magnetic field strength generated by each coil can be controlled. The magnetic fields generated by the three-dimensional coil are superimposed to obtain an arbitrarily distributed spatial magnetic field. The three-dimensional coil includes: an x-direction coil (1), a y-direction coil (2), and a z-direction coil (3). The x-direction coil (1) is located in the x-direction of the top and bottom surfaces of the system frame, the y-direction coil (2) is located in the y-direction of the top and bottom surfaces of the system frame, and the z-direction coil (3) is located on both sides of the system frame. Each group of coils in the same direction has the same number of turns and is parallel to each other. At the same time, each group of coils is located on both sides of the processing area (11) to generate a spatial magnetic field in the processing area (11). Each of the x-direction coil (1), y-direction coil (2), and z-direction coil (3) forms an independent current loop with the power source; The discrete magnet support system is located at the bottom of the workpiece (6) and is fixedly connected to the workpiece (6) to provide support force for the workpiece (6) and compensate for the deformation of the workpiece (6); The discrete magnet support system includes: a plurality of discrete magnet blocks (10) disposed on the bottom surface of the workpiece (6), which are used to convert the magnetic force received in the magnetic field into a supporting force and act on the workpiece (6); The discrete magnet blocks (10) are arranged in a single row on the bottom surface of the workpiece (6), and the spacing between adjacent discrete magnet blocks (10) is the same. The shape of each discrete magnet block (10) is adapted to the two edges of the bottom surface of the workpiece (6). The mechanical positioning system is located below the workpiece (6) and is used to place the workpiece and position it. The surface shape testing feedback system is located above the workpiece (6). It measures the surface shape of the workpiece in real time using a line laser to monitor the deformation of the workpiece (6) and provide control feedback for magnetic field adjustment. The surface shape test feedback system is used to fit the surface shape of the workpiece (6) based on the actual surface shape data of the workpiece (6) in the measurement processing area (11), and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece (6). The surface shape testing feedback system includes: a laser sensor (8), a guide rail (9), and a main control computer; There are two guide rails (9), which are horizontally fixed between two longitudinal beams on the same plane of the system frame; A slider is slidably provided between the two guide rails (9); a linear motion mechanism is provided on the bottom surface of the slider, the laser sensor (8) is vertically provided on the linear motion mechanism, and the field of view of the laser sensor (8) is vertically downward. During the horizontal displacement of the guide rail (9), the slider drives the laser sensor (8) to perform linear scanning and transverse translation along the x-axis or y-axis. During the movement, the laser sensor (8) scans downward and measures the actual surface shape data of the workpiece (6) in the processing area (11) according to the reflected signals of the emitted laser and the received laser. The computer is used to receive the reflected signal sent by the laser sensor (8), fit it into the surface shape of the workpiece, and compare it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece (6).

2. The magnetic support system for electrolytic machining of large-size thin-walled curved parts according to claim 1, characterized in that, The mechanical positioning system includes: a worktable (5) and a positioning rod (7) disposed on the worktable (5); The workbench (5) is used to place the workpiece (6); there are multiple positioning rods (7), all of which are vertically arranged on the workbench (5), and the sidewalls of the positioning rods are attached to the edge of the workpiece (6) and are tangent to the workpiece (6); The positioning rod (7) is fitted with a positioning ring, which is used to constrain the movement in three degrees of freedom, including the x-direction, y-direction and z-axis direction.

3. The magnetic support system for electrolytic machining of large-size thin-walled curved parts according to claim 1, characterized in that, The laser sensor (8) is a line laser sensor.

4. The method of using the magnetic support system for electrolytic machining of large-size thin-walled curved parts according to claim 1, characterized in that, Includes the following steps: 1) The workpiece (6) is placed on the worktable (5) and the workpiece (6) is positioned by the positioning rod (7) on the worktable (5); 2) Turn on the power of the CNC coil magnetic field generating system. The x-direction coil (1), y-direction coil (2) and z-direction coil (3) are energized to generate a magnetic field. The magnetic field distribution and intensity generated by the coil are controlled by the magnetic field control unit. The magnetic fields generated by the x-direction coil (1), y-direction coil (2) and z-direction coil (3) are superimposed on the processing area (11) to generate an arbitrarily distributed spatial magnetic field. The generated spatial magnetic field is detected by a gaussmeter (4) and fed back to the magnetic field control unit so that the computer can accurately control the magnetic field. 3) The discrete magnet support system converts the magnetic force received in the spatial magnetic field of the processing area (11) into a supporting force and acts on the workpiece (6) to compensate for the deformation of the workpiece (6); 4) The laser sensor (8) detects the deformation of the workpiece (6), and the guide rail (9) drives the laser sensor (8) to complete the full-surface scanning of the workpiece (6), and feeds back the actual surface shape data of the workpiece (6) in the measurement processing area (11) to the surface shape test feedback main control computer. 5) The main control computer fits the workpiece surface shape according to the actual surface shape data of the workpiece (6) in the measurement and processing area (11), and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece (6); 6) The main control computer adjusts the variable resistance of the loop in the three-dimensional coil to control the current through based on the workpiece deformation feedback from the laser sensor (8), thereby adjusting the spatial magnetic field strength in the processing area (11) to achieve closed-loop control.

5. The method of using the magnetic support system for electrolytic machining of large-size thin-walled curved parts according to claim 4, characterized in that, Step 3) specifically refers to: (1) The potential energy of the discrete magnet block (10) in the magnetic field is expressed as: U=-m·B ; in, m Magnetic moment, B It represents the magnetic flux density; (2) The force on the discrete magnet block (10) in the magnetic field is: F =-∇ U ; in, U Let be the potential energy of the discrete magnet block in the magnetic field; Then the supporting force of the discrete magnet block (10) in the magnetic field is obtained.

6. The method of using the magnetic support system for electrolytic machining of large-size thin-walled curved parts according to claim 4, characterized in that, The main control computer fits the workpiece surface shape based on the actual surface shape data of the workpiece (6) in the measurement processing area (11), and compares it with the theoretical surface shape of the workpiece to obtain the deformation amount of the workpiece (6), including the following steps: (1) The slider on the guide rail (9) drives the laser sensor (8) to perform fixed-step scanning according to the planned path, and ensures that the entire surface of the workpiece is scanned; (2) Record the height signal of the workpiece surface received by the laser sensor (8) and the spatial coordinates of the laser sensor (8) each time; (3) The height matrix of the complete surface of the workpiece is formed by splicing the workpiece height signal and the sensor spatial coordinates, and then the workpiece surface shape function is formed by fitting with a polynomial or other aspherical characterization function. (4) The workpiece surface shape function is subtracted from the workpiece theoretical surface shape function to obtain the workpiece deformation function, which is the amount of workpiece deformation.

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