Closed-component Electrochemical Machining Device

Abstract

The present invention discloses a closed-component electrochemical machining device and method, belonging to the field of electrochemical machining. The fixture is divided into a blade pressure surface cathode fixture and a blade suction surface cathode fixture. Each fixture is provided with a main liquid supply flow channel inlet, two auxiliary liquid supply flow channels, and two liquid sealing supply / air flow channels. The blade suction surface cathode fixture, the blade pressure surface cathode fixture, the closed component, and the electrolyte / gas ejected from the liquid sealing supply / air flow channel form a closed flow field mode in which the electrolyte in each flow channel is independently controlled. The present invention improves the uniformity and stability of the flow field in the machining area, and realizes the simultaneous machining of the internal and external flow channels and the blade profile of closed components such as rectifiers and stator vane rings; the integrated fixture is convenient for clamping and improves the electrochemical machining efficiency.

Description

Technical Field

[0001] The present invention relates to a closed-component electrochemical machining device and method, belonging to the field of electrochemical machining. Background Art

[0002] Closed-structure parts such as rectifiers and stator vane rings are new structural parts used in aeroengines. The closed-structure parts are composed of an inner ring, an outer ring, and blades. The blade structure has the characteristics of thin thickness, complex profile, and large twist degree. The narrow air flow channel between the blades makes mechanical machining difficult. The materials are mostly difficult-to-machine materials such as titanium alloys and superalloys, and the mechanical cutting performance is poor.

[0003] Electrochemical machining removes materials based on the principle of anodic dissolution of metals in an electrolyte. During machining, a pre-shaped cathode is used to form the workpiece. Electrochemical machining has many advantages such as high machining efficiency, no loss of the tool cathode, good machining surface quality, and wide machining range. It has been widely used in industries such as aerospace and ordnance, and has become the mainstream manufacturing method for complex-shaped workpieces made of difficult-to-machine materials in domestic and foreign aeroengines.

[0004] Among the numerous influencing factors in electrochemical machining, the rationality of the flow field design directly affects the machining accuracy and stability of electrochemical machining. A good electrolyte flow field can quickly carry away the electrochemical machining products, bubbles, and heat generated during machining from the machining area. Regarding the flow field mode of electrochemical machining, Nanjing University of Aeronautics and Astronautics proposed a three-dimensional composite flow field mode (see the patent "Integral blisk profile electrochemical machining device and method based on three-dimensional composite flow field", application number 201300453340.8, applicant Nanjing University of Aeronautics and Astronautics, inventors Liu Jia, Wan Longkai, Xu Zhengyang, Zhu Dong). In this flow field mode, liquid is supplied in a composite manner from the leading edge to the trailing edge and from the blade root to the blade tip, effectively solving the problem of uneven electrolyte flow distribution in the side-flow type flow field. Nanjing University of Aeronautics and Astronautics also proposed a flow field mode of supplying liquid to the entire profile of the blade (see the patent "Integral blisk electrochemical machining device and method of supplying liquid to the entire profile of the blade", application number 202010730223.9, applicant Nanjing University of Aeronautics and Astronautics, inventors Zhu Dong, Guo Jianwei, Zhu Di). In this flow field mode, electrolyte is supplied to the suction side, pressure side, leading edge, and trailing edge of the blade respectively, improving the flow field uniformity in the machining area. Shenyang Liming Aero-Engine (Group) Co., Ltd. adopted an open electrolyte flow mode, with the main liquid flowing into the blade from the blade tip and two auxiliary liquids flowing into the blade from the blade roots at the leading edge and trailing edge respectively (see the patent "An integral blisk blade profile micro electrochemical machining electrode and machining method", application number 201210269950.5, applicant Shenyang Liming Aero-Engine (Group) Co., Ltd., inventors Zhu Hainan, Yu Bing, etc.). The above several flow field modes are all proposed for the integral blisk with an open structure and are not applicable to closed structure integral components such as rectifiers and stator vane rings. For new structure parts such as rectifiers and stator vane rings with a closed structure, there is currently no practical and available flow field, and it is necessary to design a flow field mode suitable for the all-round electrochemical machining of closed structure parts. Summary of the Invention

[0005] The present invention proposes a tool and fixture integrated, all-round liquid supply electrochemical machining device and method for closed components, which meets the flow field requirements for simultaneous machining of the blade profile and the internal and external flow channels of closed components, ensures the stability of the electrolyte flow field, prevents electrolyte leakage from the machining area to a certain extent, and the integrated fixture design improves the machining efficiency, realizing the stable all-round machining of closed components.

[0006] An electrochemical fine machining device for closed components with a tool and fixture integrated and all-round liquid supply, wherein the closed component is composed of an inner ring, blades, and an outer ring; it is characterized in that:

[0007] The area between the suction side of the blade to be machined and the pressure side of the adjacent blade is called the suction-side cathode channel. The suction-side cathode is located in the suction-side cathode channel. The suction-side cathode includes a suction-side cathode machining surface and a suction-side cathode insulation surface. The area between the suction-side cathode and the inner ring is called the suction-side inner flow passage machining area, and beside the suction-side inner flow passage machining area is the non-machining area of the suction-side inner flow passage. The area between the suction-side cathode and the outer ring is called the suction-side outer flow passage machining area, and beside the suction-side outer flow passage machining area is the non-machining area of the suction-side outer flow passage;

[0008] The area between the pressure side of the blade to be machined and the suction side of the adjacent blade is called the pressure-side cathode channel. The pressure-side cathode is located in the pressure-side cathode channel. The pressure-side cathode includes a pressure-side cathode machining surface and a pressure-side cathode insulation surface. The area between the pressure-side cathode and the inner ring is called the pressure-side inner flow passage machining area, and beside the pressure-side inner flow passage machining area is the non-machining area of the pressure-side inner flow passage. The area between the pressure-side cathode and the outer ring is called the pressure-side outer flow passage machining area, and beside the pressure-side outer flow passage machining area is the non-machining area of the pressure-side outer flow passage;

[0009] The device includes a suction-side cathode fixture and a pressure-side cathode fixture;

[0010] The suction-side cathode fixture is located above the suction-side cathode channel of the blade to be machined and is connected to the suction-side cathode below; the pressure-side cathode fixture is located above the pressure-side cathode channel and is connected to the pressure-side cathode below;

[0011] The device includes three electrolyte flow channels, namely: the main liquid supply channel for supplying liquid to the blade machining area, the auxiliary liquid supply channel for supplying liquid to the inner and outer flow passage machining areas, and the liquid sealing / air flow channel for sealing the non-machining areas of the inner and outer flow passages;

[0012] Among them, the main liquid supply channel includes a suction-side liquid inlet channel, a pressure-side liquid inlet channel, and a blade machining area flow channel; the suction-side liquid inlet channel and the pressure-side liquid inlet channel are respectively located in the middle parts of the suction-side cathode fixture and the pressure-side cathode fixture; the blade machining area flow channel is the area formed between the suction-side cathode machining surface, the pressure-side cathode machining surface and the blade to be machined of the closed member; the main liquid supply channel for supplying liquid to the blade machining area and the auxiliary liquid supply channel for supplying liquid to the inner and outer flow passage machining areas have an overall liquid supply mode in the shape of "I";

[0013] Among them, the auxiliary liquid supply channel includes a first auxiliary liquid supply channel, a second auxiliary liquid supply channel, a third auxiliary liquid supply channel, and a fourth auxiliary liquid supply channel; the first auxiliary liquid supply channel is located in the suction-side cathode fixture and supplies liquid to the suction-side inner flow passage machining area; the second auxiliary liquid supply channel is located in the suction-side cathode fixture and supplies liquid to the suction-side outer flow passage machining area; the third auxiliary liquid supply channel is located in the pressure-side cathode fixture and supplies liquid to the pressure-side inner flow passage machining area; the fourth auxiliary liquid supply channel is located in the pressure-side cathode fixture and supplies liquid to the pressure-side outer flow passage machining area;

[0014] The liquid sealing supply / air flow channels include a first liquid sealing supply / air flow channel, a second liquid sealing supply / air flow channel, a third liquid sealing supply / air flow channel, and a fourth liquid sealing supply / air flow channel. The first liquid sealing supply / air flow channel is located in the blade suction side cathode fixture body, and supplies liquid to the non-machining area of the inner flow channel of the blade suction side to achieve liquid sealing of the machining area of the inner flow channel of the blade suction side. The second liquid sealing supply / air flow channel is located in the blade suction side cathode fixture body, and supplies liquid to the non-machining area of the outer flow channel of the blade suction side to achieve liquid sealing of the machining area of the outer flow channel of the blade suction side. The third liquid sealing supply / air flow channel is located in the blade pressure side cathode fixture body, and supplies liquid to the non-machining area of the inner flow channel of the blade pressure side to achieve liquid sealing of the machining area of the inner flow channel of the blade pressure side. The fourth liquid sealing supply / air flow channel is located in the blade pressure side cathode fixture body, and supplies liquid to the non-machining area of the outer flow channel of the blade pressure side to achieve liquid sealing of the machining area of the outer flow channel of the blade pressure side.

[0015] The method of the closed member electrochemical machining device with integrated tool and tooling and all-round liquid supply according to the present invention is characterized in that:

[0016] The electrolyte flow directions of the main liquid supply channel and the four auxiliary liquid supply channels are all from the blade inlet edge to the blade outlet edge or from the blade outlet edge to the blade inlet edge.

[0017] Before machining starts, the blade suction side cathode and the blade pressure side cathode are respectively inserted into the blade suction side cathode channel and the blade pressure side cathode channel driven by the blade suction side cathode fixture body and the blade pressure side cathode fixture body, and enter the machining position.

[0018] The liquid inlet pressures of the two liquid inlets of the blade suction side liquid inlet channel and the blade pressure side liquid inlet channel in the main liquid supply channel are the same. The pressures of the four auxiliary liquid supply channels are the same, but higher than the liquid inlet pressures of the blade suction side liquid inlet channel and the blade pressure side liquid inlet channel, to ensure uniform electrolyte in the blade machining area. The pressures of the four liquid sealing supply / air flow channels are the same, but higher than the pressures of the auxiliary liquid supply channels, to ensure sufficient electrolyte in the machining areas of the inner and outer flow channels and no external leakage.

[0019] When machining starts, the blade suction side cathode and the blade pressure side cathode are respectively driven by the blade suction side cathode fixture body and the blade pressure side cathode fixture body to relatively feed, to achieve all-round machining of the blade profile and the inner and outer flow channels of the closed member.

[0020] After machining is completed, the cathode retracts to a safe distance, the closed member retracts to a safe distance, after rotating a certain angle, the cathode returns to the machining position, and the machining of the next blade is carried out, and finally the forming machining of all blades of the closed member is completed.

[0021] The beneficial effects of the present invention are as follows:

[0022] A liquid flow mode with all-round liquid supply is proposed, which realizes the simultaneous machining of the blade profiles and the inner and outer flow channels of closed structure parts such as rectifiers and stator vane rings, and improves the machining efficiency.

[0023] There are three types of flow channels: the main liquid supply channel, the auxiliary liquid supply channel, and the sealing liquid / gas supply channel. The liquid inlet pressure of the auxiliary liquid supply channel is higher than that of the main liquid supply channel, ensuring sufficient electrolyte in the blade profile machining area of the closed component; the liquid inlet pressure of the sealing liquid / gas supply channel is higher than that of the auxiliary liquid supply channel, ensuring sufficient electrolyte in the machining areas of the inner and outer flow channels of the closed component, improving the sealing of the flow field, and enhancing machining stability.

[0024] The tool cathode and the tooling fixture are designed as an integrated structure, which is conducive to automation. The cathode body of the blade concave surface and the cathode body of the blade convex surface feed and retract simultaneously, reducing the tooling clamping process and shortening the manufacturing cycle.

[0025] It has strong adaptability and is suitable for machining different types of closed components. The flow field structure form of the present invention can be used to machine different models of closed components. According to the different blade profiles and sizes of the machined workpieces, the parameters of each part can be adjusted to achieve stable machining in all aspects. Brief Description of the Drawings

[0026] Figure 1 Overall Assembly Schematic Diagram of the Back

[0027] Figure 2 Overall Assembly Schematic Diagram of the Front

[0028] Figure 3 Schematic Diagram of the Omnidirectional Liquid Supply Mode

[0029] Figure 4 Schematic Diagram of the Closed Component

[0030] Names of the Reference Numerals in the Figures: 1. Closed Component, 2. Third Sealing Liquid / Gas Supply Channel, 3. Third Auxiliary Liquid Supply Channel, 4. Fourth Auxiliary Liquid Supply Channel, 5. Fourth Sealing Liquid / Gas Supply Channel, 6. Liquid Inlet Channel of the Blade Convex Surface, 7. Specific Cathode Clamp of the Blade Convex Surface, 8. Specific Cathode Clamp of the Blade Concave Surface, 9. Liquid Inlet Channel of the Blade Concave Surface, 10. Second Sealing Liquid / Gas Supply Channel, 11. Second Auxiliary Liquid Supply Channel, 12. First Auxiliary Liquid Supply Channel, 13. First Sealing Liquid / Gas Supply Channel, 14. Cathode Channel of the Blade Concave Surface, 15. Non-Machining Area of the Outer Flow Channel of the Blade Concave Surface, 16. Insulating Surface of the Cathode of the Blade Concave Surface, 17. Machining Area of the Outer Flow Channel of the Blade Concave Surface, 18. Machining Area of the Outer Flow Channel of the Blade Convex Surface, 19. Non-Machining Area of the Outer Flow Channel of the Blade Convex Surface, 20. Insulating Surface of the Cathode of the Blade Convex Surface, 21. Cathode of the Blade Convex Surface, 22. Cathode Channel of the Blade Convex Surface, 23. Non-Machining Area of the Inner Flow Channel of the Blade Convex Surface, 24. Machining Area of the Inner Flow Channel of the Blade Convex Surface, 25. Flow Channel in the Blade Machining Area, 26. Machining Area of the Inner Flow Channel of the Blade Concave Surface, 27. Non-Machining Area of the Inner Flow Channel of the Blade Concave Surface, 28. Cathode of the Blade Concave Surface, 29. Machining Surface of the Cathode of the Blade Convex Surface, 30. Machining Surface of the Cathode of the Blade Concave Surface, 31. Outer Flow Channel Surface of the Closed Component, 32. Exhaust Edge of the Blade, 33. Intake Edge of the Blade, 34. Inner Flow Channel Surface of the Closed Component, 35. Liquid Outlet. Specific Implementation Method

[0031] The following is a detailed introduction to the specific implementation process of the present invention in conjunction with the accompanying drawings:

[0032] The process of electrolytically machining a workpiece using the "closed-component electrolytic machining device and method" of the present invention includes the following steps:

[0033] Step 1: Install the integral closed component 1, the specific blade concave cathode clamp 8, and the specific blade convex cathode clamp 7. The specific blade concave cathode clamp 8 and the specific blade convex cathode clamp 7 are respectively installed on the numerically controlled motion axes moving linearly in opposite directions and are connected to the negative pole of the power supply. The closed component 1 is installed on the rotating platform, and the fixture plate is connected to the positive pole of the power supply. The blade concave cathode 28 and the blade convex cathode 21 are respectively inserted into the blade concave cathode channel 14 and the blade convex cathode channel 22.

[0034] Step 2: Supply the electrolyte. Adopting the all-round liquid supply electrolyte flow mode, the prepared electrolyte is supplied to the blade machining area flow channel 25, the blade concave internal flow channel machining area 26, the blade concave external flow channel machining area 17, the blade convex internal flow channel machining area 24, and the blade convex external flow channel machining area 18 at a certain pressure, temperature, and concentration through the main liquid supply flow channel and the auxiliary liquid supply flow channel. Then, the electrolyte or gas with the same parameters is used to seal the machining area through the liquid / gas sealing flow channel. The inlet pressure of the auxiliary liquid supply flow channel is greater than the inlet pressures of the blade concave liquid inlet channel and the blade convex liquid inlet channel, and the inlet pressure of the liquid / gas sealing flow channel is greater than the inlet pressure of the auxiliary liquid supply flow channel.

[0035] Step 3: Connect the electrolytic machining power supply. The specific blade concave cathode clamp 8 and the specific blade convex cathode clamp 7 are driven by the numerically controlled motion axes moving linearly in opposite directions to relatively feed, realizing the all-round machining of the blades and the internal and external flow channel surfaces of the closed component. After machining is completed, the cathode retracts to a safe distance, the closed component retracts to a safe distance, the closed component rotates by a certain angle, the blade concave cathode 28 and the blade convex cathode 21 return to the machining position, and the machining of the next blade is carried out, finally completing the machining of all the blades and air flow channels of the closed component.

[0036] Step 4: After machining is completed, disconnect the electrolytic machining power supply, turn off the pump in the electrolyte circulation system loop, and return each machining axis of the machine tool to the initial position.

Claims

1. A closed - type component electro - finishing device, wherein the closed - type component is composed of an inner ring, blades, and an outer ring; characterized in that: The area between the blade suction side of the blade to be processed and the pressure side of the adjacent blade is called the suction - side cathode channel (14). The suction - side cathode (28) is located in the suction - side cathode channel (14). The suction - side cathode (28) includes a suction - side cathode machining surface (30) and a suction - side cathode insulation surface (16). The area between the suction - side cathode (28) and the inner ring is called the inner flow - path machining area of the suction - side (26). Next to the inner flow - path machining area of the suction - side (26) is the non - machining area of the inner flow - path of the suction - side (27). The area between the suction - side cathode (28) and the outer ring is called the outer flow - path machining area of the suction - side (17). Next to the outer flow - path machining area of the suction - side (17) is the non - machining area of the outer flow - path of the suction - side (15); The area between the pressure side of the blade to be processed and the suction side of the adjacent blade is called the pressure - side cathode channel (22). The pressure - side cathode (21) is located in the pressure - side cathode channel (22). The pressure - side cathode (21) includes a pressure - side cathode machining surface (29) and a pressure - side cathode insulation surface (20). The area between the pressure - side cathode (21) and the inner ring is called the inner flow - path machining area of the pressure - side (24). Next to the inner flow - path machining area of the pressure - side (24) is the non - machining area of the inner flow - path of the pressure - side (23). The area between the pressure - side cathode (21) and the outer ring is called the outer flow - path machining area of the pressure - side (18). Next to the outer flow - path machining area of the pressure - side (18) is the non - machining area of the outer flow - path of the pressure - side (19); The device includes a suction - side cathode fixture (8) and a pressure - side cathode fixture (7); The suction - side cathode fixture (8) is located above the suction - side cathode channel (14) of the blade to be processed and is connected to the suction - side cathode (28) below; the pressure - side cathode fixture (7) is located above the pressure - side cathode channel (22) and is connected to the pressure - side cathode (21) below; The device includes three kinds of electrolyte flow channels, namely: the main liquid - supply flow channel for supplying liquid to the blade machining area, the auxiliary liquid - supply flow channel for supplying liquid to the inner and outer flow - path machining areas, and the liquid - sealing / air - flow channel for sealing the non - machining areas of the inner and outer flow - paths; Among them, the main liquid - supply flow channel includes a suction - side liquid - inlet channel (9), a pressure - side liquid - inlet channel (6), and a blade machining - area flow channel (25). Among them, the suction - side liquid - inlet channel (9) and the pressure - side liquid - inlet channel (6) are respectively located in the middle parts of the suction - side cathode fixture (8) and the pressure - side cathode fixture (7). The blade machining - area flow channel (25) is the area formed between the suction - side cathode machining surface (30), the pressure - side cathode machining surface (29), and the blade to be processed of the closed - type component. The main liquid - supply flow channel for supplying liquid to the blade machining area and the auxiliary liquid - supply flow channel for supplying liquid to the inner and outer flow - path machining areas have an overall liquid - supply mode in the shape of "I"; The auxiliary liquid supply channels include a first auxiliary liquid supply channel (12), a second auxiliary liquid supply channel (11), a third auxiliary liquid supply channel (3), and a fourth auxiliary liquid supply channel (4); the first auxiliary liquid supply channel (12) is located in the blade suction side cathode fixture (8) to supply liquid to the inner flow channel processing area (26) of the blade suction side; the second auxiliary liquid supply channel (11) is located in the blade suction side cathode fixture (8) to supply liquid to the outer flow channel processing area (17) of the blade suction side; the third auxiliary liquid supply channel (3) is located in the blade pressure side cathode fixture (7) to supply liquid to the inner flow channel processing area (24) of the blade pressure side; the fourth auxiliary liquid supply channel (4) is located in the blade pressure side cathode fixture (7) to supply liquid to the outer flow channel processing area (18) of the blade pressure side; The sealing liquid supply / air channels include a first sealing liquid supply / air channel (13), a second sealing liquid supply / air channel (10), a third sealing liquid supply / air channel (2), and a fourth sealing liquid supply / air channel (5); the first sealing liquid supply / air channel (13) is located in the blade suction side cathode fixture (8) to supply liquid to the non-processing area (27) of the inner flow channel of the blade suction side to seal the inner flow channel processing area (26) of the blade suction side; the second sealing liquid supply / air channel (10) is located in the blade suction side cathode fixture (8) to supply liquid to the non-processing area (15) of the outer flow channel of the blade suction side to seal the outer flow channel processing area (17) of the blade suction side; the third sealing liquid supply / air channel (2) is located in the blade pressure side cathode fixture (7) to supply liquid to the non-processing area (23) of the inner flow channel of the blade pressure side to seal the inner flow channel processing area (24) of the blade pressure side; the fourth sealing liquid supply / air channel (5) is located in the blade pressure side cathode fixture (7) to supply liquid to the non-processing area (19) of the outer flow channel of the blade pressure side to seal the outer flow channel processing area (18) of the blade pressure side.

2. A method for using the closed member electrochemical machining device according to claim 1, characterized in that: The electrolyte flow directions of the main liquid supply channel and the four auxiliary liquid supply channels are all from the blade inlet edge to the blade outlet edge or from the blade outlet edge to the blade inlet edge; Before the machining starts, the blade suction side cathode (28) and the blade pressure side cathode (21) are respectively inserted into the blade suction side cathode channel (14) and the blade pressure side cathode channel (22) driven by the blade suction side cathode fixture (8) and the blade pressure side cathode fixture (7) and enter the machining position; The liquid inlet pressures of the two liquid inlet ports of the blade suction side liquid inlet channel (9) and the blade pressure side liquid inlet channel (6) in the main liquid supply channel are the same; the pressures of the four auxiliary liquid supply channels are the same, but higher than the liquid inlet pressures of the blade suction side liquid inlet channel (9) and the blade pressure side liquid inlet channel (6) to ensure uniform electrolyte in the blade machining area; the pressures of the four sealing liquid supply / air channels are the same, but higher than the pressures of the auxiliary liquid supply channels to ensure sufficient electrolyte in the inner and outer flow channel processing areas and no external leakage; When the machining starts, the blade suction side cathode (28) and the blade pressure side cathode (21) are respectively driven by the blade suction side cathode fixture (8) and the blade pressure side cathode fixture (7) to relatively feed, realizing all-round machining of the blade profile and the inner and outer flow channels of the closed member; After the machining is completed, the cathode retracts to a safe distance, the closed member (1) retracts to a safe distance, and after rotating a certain angle, the cathode returns to the machining position to machine the next blade, and finally complete the forming machining of all blades of the closed member (1).

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