Modular electro-discharge-electrolytic milling tool and method

Abstract

The application relates to a modular electrolytic discharge-electrolytic milling machining tool and method, and belongs to the technical field of special machining. The application adjusts the strength and action area of the discharge action and electrolysis action in the electrolytic discharge composite milling machining by assembling electrolytic discharge machining modules and electrolytic machining modules with different thicknesses and end face inclination angles at the cathode end of the tool, so that the discharge action and electrolysis action are efficiently coordinated. In the modular electrolytic discharge-electrolytic milling machining, the workpiece is first subjected to rapid material removal by electrolytic discharge machining in the same process, and then the defects such as the recast layer existing on the surface of the workpiece are eliminated by electrolytic machining, so that efficient high-surface-quality machining is realized.

Description

Technical Field

[0001] This invention relates to a modular electrolytic de-electrolytic milling tool and method, belonging to the field of special machining technology. Background Technology

[0002] Electrochemical machining (ECM) is a machining technique that utilizes the principle of anodic electrochemical dissolution of metallic materials in an electrolyte solution to shape the workpiece. Electrochemical discharge occurs when hydrogen gas evolved on the cathode surface during electrolysis undergoes breakdown discharge under a high electric field. Electrical discharge machining (EDM) uses the high temperatures generated by the discharge to cause localized, momentary melting or vaporization of the workpiece material, thereby removing it. EDM of conductive materials combines both electrochemical dissolution and electrochemical discharge, making it a composite machining technology. This non-contact machining technique has significant application potential in machining traditionally difficult-to-cut materials such as titanium alloys and nickel-based superalloys.

[0003] Electro-hydraulic milling combines electro-hydraulic machining with CNC machine tools. Through CNC programming, the tool electrode completes the forming of various complex structures on the workpiece surface. It inherits the advantages of electro-hydraulic machining technology, such as not being limited by the mechanical properties of the workpiece material, and also has the flexibility and automation of CNC machining, thus having good machining flexibility.

[0004] In electrolytic-electrical hybrid machining, both electrolysis and discharge have their own advantages and disadvantages. For example, electrolysis offers high surface finish, but its material removal efficiency is lower than that of electrical discharge machining (EDM); while EDM offers high material removal efficiency, it struggles to achieve damage-free, high-integrity surface finishes, and the machined surface is prone to defects such as recast layers and heat-affected zones. In electrolytic-electrical hybrid machining, balancing the electrolysis and discharge effects is crucial. When the electrolysis is too strong and the discharge is insufficient, the electrolytic-electrical hybrid machining cannot fully utilize the high-efficiency processing advantage of discharge; conversely, when the discharge is too strong and the electrolysis is insufficient, the electrolysis cannot adequately remove defects such as recast layers formed on the workpiece surface due to discharge, resulting in poor surface finish. Therefore, only by achieving a balance between electrolysis and discharge can the advantages of both be fully utilized and their disadvantages compensated for in electrolytic-electrical hybrid machining.

[0005] Currently, electrolytic-discharge hybrid machining mainly adjusts the balance between electrolytic and discharging effects during processing by changing the working fluid or processing voltage. For example, a low-conductivity solution or high processing voltage can make the discharging effect dominant, while a high-conductivity solution or low processing voltage can make the electrolytic effect dominant. However, both changing the working fluid and processing voltage have limitations in processing. They not only increase the requirements for the electrolyte and power supply equipment, but also cannot achieve the control of electrolytic and discharging effects in different processing areas of the workpiece surface. Summary of the Invention

[0006] This invention proposes a modular electrolytic-electrolytic milling tool and method. Through a simple tool electrode structure, the intensity and area of ​​electrolytic and discharge effects in electrolytic-electrolytic composite milling are controlled. The electrolytic discharge effect during processing is used to quickly remove workpiece material, while the electrolytic effect during processing is used to eliminate defects such as recast layers formed on the workpiece surface due to discharge, thereby achieving high-efficiency milling with high surface quality.

[0007] A modular electrolytic discharge-electrolytic milling tool is characterized by comprising a tool cathode, an electrolytic machining module, an electrolytic discharge-electrolytic machining module, and an automatic sealing device. The electrolytic machining module and the electrolytic discharge-electrolytic machining module are mounted on the end of the tool cathode. The electrolytic discharge-electrolytic machining module is located in front of and connected to the electrolytic machining module. Both the electrolytic discharge-electrolytic machining module and the electrolytic machining module have inclined angles, with the inclined angle of the electrolytic discharge-electrolytic machining module's end face being greater than that of the electrolytic machining module's end face. Furthermore, the rear edge of the electrolytic discharge-electrolytic machining module's end face coincides with the front edge of the electrolytic machining module's end face. The automatic sealing device is located behind the electrolytic machining module. The tool cathode has an electrolyte flow channel located at the rear of the tool cathode and extending through the entire tool cathode, flowing out from the rear of the electrolytic machining module. After being blocked by the automatic sealing device, the electrolyte flows from back to front through the machining gap between the electrolytic machining module, the electrolytic discharge-electrolytic machining module, and the workpiece surface. The tool cathode is made of conductive metal, the electrolytic machining module is made of conductive metal, and the electrolytic discharge-electrolytic machining module is made of high-temperature resistant conductive metal.

[0008] The modular electrolytic discharge-electrolytic milling tool is characterized by the following: the electrolytic processing module and the electrolytic discharge-electrolytic processing module are detachable structures, and their thickness and / or end face tilt angle are adjustable. Different electrolytic discharge-electrolytic processing modules and electrolytic processing modules are selected and assembled according to the actual processing conditions. The greater the thickness and end face tilt angle of the electrolytic discharge-electrolytic processing module, the larger the area of ​​the tilted end face used for electrolytic discharge-electrolytic processing, resulting in higher material removal efficiency for the workpiece. Conversely, the greater the thickness of the electrolytic processing module, the larger the area of ​​the tilted end face used for electrolytic processing, the greater the amount of electricity used for electrolysis, and the more thoroughly defects such as the recast layer on the workpiece surface are removed, resulting in better surface processing quality. The selection of the end face tilt angle of the electrochemical machining module is related to the milling speed of the tool: with other parameters remaining unchanged, increasing the milling speed will reduce the machining gap between the electrochemical machining module and the workpiece, while decreasing the end face tilt angle of the electrochemical machining module can increase the machining gap between the electrochemical machining module and the workpiece. Therefore, under faster milling speed conditions, an electrochemical machining module with a smaller end face tilt angle is selected, while under slower milling speed conditions, an electrochemical machining module with a larger end face tilt angle is selected, thereby controlling the machining gap between the electrochemical machining module and the workpiece within a suitable range.

[0009] The method for using the modular electrolytic discharge-electrolytic milling tool is characterized by the following steps: selecting a suitable electrolytic machining module and an electrolytic discharge-electrolytic machining module according to actual machining requirements and installing them on the tool cathode; connecting the assembled modular electrolytic discharge-electrolytic milling tool to the CNC machine tool spindle via a fixture, with the electrolyte flow channel inside the tool cathode connected to the electrolyte pipe held by the machine tool spindle; connecting the tool cathode to the negative terminal of the machining power supply; clamping the workpiece to be machined on the machine tool work platform and connecting it to the positive terminal of the machining power supply; adjusting the relative position of the machining tool and the workpiece so that the machining tool is directly above the starting point of the workpiece machining; opening the electrolyte supply valve, allowing the electrolyte to be sprayed onto the workpiece surface through the electrolyte flow channel inside the tool cathode; simultaneously turning on the machining power supply and controlling the tool cathode to feed downwards for machining, and after reaching the specified depth of cut, controlling the tool to feed horizontally along a preset trajectory for milling; during the machining process, the electrolytic discharge-electrolytic machining module is located at the foremost position of the tool cathode in the milling direction, followed by the electrolytic machining module and the automatic sealing device in sequence; due to the large tilt angle of the end face of the electrolytic discharge-electrolytic machining module... With the electrolytic machining module's end face tilted at an angle, the gap between the electrolytic machining module's end face and the workpiece is greater than that between the electrolytic discharge machining module's end face and the workpiece. Under the same anode-cathode potential difference, the electrolytic discharge machining module and the workpiece have a higher electric field strength due to the smaller gap. Since the electric field strength threshold for discharge is higher than that for electrolysis, the intensity and area of ​​discharge and electrolysis can be controlled. The workpiece first undergoes rapid material removal via electrolytic discharge machining, and then surface recasting and other defects are removed by electrolysis, thus achieving efficient and high-quality surface processing. The automatic sealing device constrains the flow of electrolyte, ensuring that the electrolyte, after being ejected from the flow channel, flows entirely through the electrolytic machining module and the processing gap between the electrolytic discharge machining module and the workpiece surface, and significantly increases the electrolyte flow rate through the back pressure effect. The rapid flow of electrolyte can promptly break the plasma arc between the electrolytic discharge machining module and the workpiece, preventing continuous arcing from burning the tool and workpiece surfaces. The rapid flow of electrolyte can also promptly discharge processing products, avoiding short circuits caused by processing products clogging the processing gap.

[0010] The modular electrolytic discharge-electrolytic milling tool is characterized in that: the automatic sealing device includes a guide rod, a linear bearing, a bearing housing, a spring, a baffle slider, and a baffle; the upper end of the guide rod is installed in the bearing housing through the linear bearing, the baffle slider is installed at the lower end of the guide rod, and the baffle is installed below the front side of the baffle slider; the spring is located between the bearing housing and the baffle slider and is fitted onto the guide rod.

[0011] A modular electrolytic electro-milling machining tool, characterized by including a tool cathode and an automatic sealing device.

[0012] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention can control the discharge and electrolysis effects in electro-discharge combined milling. By combining electro-discharge machining modules and electrolysis machining modules with different thicknesses and end-face inclination angles, the intensity and area of ​​the discharge and electrolysis effects during machining can be controlled to achieve efficient synergy between the discharge and electrolysis effects. The electro-discharge machining module and electrolysis machining module on the tool cathode have the advantage of flexible replacement. When the tool cathode is severely worn due to discharge, only the corresponding machining module needs to be replaced. This invention can break the discharge channel by accelerating the flow of electrolyte, thereby achieving timely arc interruption. Therefore, this invention does not require a pulse power supply as in traditional discharge machining. The machining power supply can be a pulse power supply or a non-pulse power supply, reducing the requirements for power supply equipment. Attached Figure Description

[0013] Figure 1 A schematic diagram of a modular electrolytic de-electrolytic milling machining tool; Figure 2 A schematic diagram of modular electrolytic de-electrolytic milling machining; The labels are as follows: 1. Tool cathode, 2. Electrolytic machining module, 3. Electrolytic discharge electrolytic machining module, 4-1. Linear bearing, 4-2. Guide rod, 4-3. Bearing housing, 4-4. Spring, 4-5. Baffle slider, 4-6. Baffle, 5. Tool feed direction, 6. Electrolyte flow direction, 7. Workpiece, 8-1. Electrolytic discharge electrolytic machining area, 8-2. Electrolytic machining area. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings: like Figure 1As shown, the modular electro-electro-electro-milling tool proposed in this invention includes a tool cathode, an electro-milling module, an electro-electro-electro-milling module, and an automatic sealing device. By assembling electro-electro-electro-milling modules and electro-milling modules with different thicknesses and end-face inclination angles on the tool cathode, the intensity and application area of ​​the discharge and electrolysis effects during machining can be controlled. While leveraging the advantages of efficient material removal through discharge, the electrolysis effect is used to eliminate defects such as recast layers on the machined surface, thus achieving efficient synergy between discharge and electrolysis effects.

[0015] like Figure 2 As shown, because the tilt angle of the electrolytic discharge module's end face is greater than that of the electrolytic machining module's end face, the gap between the electrolytic machining module's end face and the workpiece is greater than that between the electrolytic discharge module's end face and the workpiece. Under the same anode-cathode potential difference, the electrolytic discharge module has a higher electric field strength due to the smaller gap between it and the workpiece. By utilizing the difference in electric field strength required for discharge and electrolysis to occur, the intensity and application area of ​​discharge and electrolysis can be controlled. First, the electrolytic discharge module rapidly removes material from the workpiece, and then the electrolytic machining module removes defects such as the recast layer on the workpiece surface, thereby achieving efficient and high-surface-quality machining.

[0016] The specific processing steps are as follows: Step 1: Select the appropriate electrolytic discharge machining module and electrolytic machining module according to the actual processing requirements and install them on the tool cathode.

[0017] Step 2: Connect the assembled modular electro-electro-milling tool to the CNC machine tool spindle via a fixture. Connect the electrolyte channel inside the tool cathode to the electrolyte pipe held by the machine tool spindle. Connect the tool cathode to the negative terminal of the machining power supply.

[0018] Step 3: Clamp the workpiece to be processed on the machine tool work platform and connect it to the positive terminal of the processing power supply.

[0019] Step 4: Adjust the relative position of the machining tool and the workpiece so that the machining tool is directly above the starting point of the workpiece and the baffle is in contact with the workpiece, and the spring inside the automatic sealing device is pressed.

[0020] Step 5: Open the electrolyte supply valve, and the electrolyte will be sprayed onto the workpiece surface through the electrolyte channel inside the tool cathode.

[0021] Step 5: While turning on the machining power, control the tool to feed downwards for machining. After reaching the specified depth of cut, control the tool to feed horizontally along the preset trajectory to perform milling.

[0022] Step Six: After completing the processing, turn off the power and electrolyte, and move the tool back to its initial position.

Claims

1. A modular electrolytic electro-milling machining tool, characterized in that: It consists of a tool cathode (1), an electrolytic machining module (2), an electrolytic discharge electrolytic machining module (3), and an automatic sealing device; the electrolytic machining module (2) and the electrolytic discharge electrolytic machining module (3) are installed at the end of the tool cathode (1); The aforementioned electrolytic electrochemical processing module (3) is located in front of and connected to the electrolytic processing module (2); Both the end faces of the electrolytic discharge machining module (3) and the electrolytic machining module (2) have an inclination angle. The inclination angle of the end face of the electrolytic discharge machining module (3) is greater than that of the end face of the electrolytic machining module (2). Furthermore, the rear edge of the end face of the electrolytic discharge machining module (3) coincides with the front edge of the end face of the electrolytic machining module (2). The aforementioned automatic sealing device is located on the rear side of the electrolytic processing module (2); The tool cathode (1) has an electrolyte flow channel inside. The electrolyte flow channel is located at the rear of the tool cathode and runs through the entire tool cathode (1). The electrolyte flows in from the rear of the electrolytic machining module (2), and after being blocked by the automatic sealing device, it flows from back to front through the machining gap between the electrolytic machining module (2), the electrolytic electrolytic machining module (3) and the workpiece (7). The cathode (1) of the above-mentioned tool is made of conductive metal, the electrolytic processing module (2) is made of conductive metal, and the electrolytic discharge processing module (3) is made of high-temperature resistant conductive metal. The electrolytic machining module (2) and the electrolytic discharge machining module (3) are detachable structures, and their thickness and / or end face tilt angle are adjustable. Different electrolytic discharge machining modules and electrolytic machining modules are selected and assembled according to the actual processing conditions. The greater the thickness and the greater the inclination angle of the end face of the electro-electro-electro-machining module (3), the larger the area of ​​the inclined end face of the electro-electro-electro-machining module (3) used for electro-electro-electro-machining, and the higher the material removal efficiency of the workpiece. The greater the thickness of the electrolytic machining module (2), the larger the area of ​​the inclined end face of the electrolytic machining module (2) used for electrolytic machining, the greater the amount of electricity used for electrolytic action, the more thoroughly the defects of the recast layer on the surface of the workpiece are removed, and the better the surface machining quality is obtained. The selection of the end face tilt angle of the electrolytic machining module (2) is related to the milling speed of the tool: when other parameters remain unchanged, increasing the milling speed will reduce the machining gap between the electrolytic machining module (2) and the workpiece, while reducing the end face tilt angle of the electrolytic machining module (2) can increase the machining gap between the electrolytic machining module (2) and the workpiece. Therefore, under the condition of faster milling speed, an electrolytic machining module (2) with a smaller end face tilt angle is selected, while under the condition of slower milling speed, an electrolytic machining module (2) with a larger end face tilt angle is selected, thereby controlling the machining gap between the electrolytic machining module (2) and the workpiece to be within a suitable range.

2. The modular electrolytic electro-electrolytic milling tool according to claim 1, characterized in that: The aforementioned automatic sealing device includes a guide rod (4-2), a linear bearing (4-1), a bearing housing (4-3), a spring (4-4), a baffle slider (4-5), and a baffle (4-6). The upper end of the guide rod (4-2) is installed inside the bearing housing (4-3) via the linear bearing (4-1), the baffle slider (4-5) is installed at the lower end of the guide rod (4-2), and the baffle (4-6) is installed below the front side of the baffle slider (4-5). The spring (4-4) is located between the bearing housing (4-3) and the baffle slider (4-5) and is fitted onto the guide rod (4-2).

3. The method of using the modular electrolytic discharge-electrolytic milling machining tool as described in claim 1, Its characteristics include the following processes: Select the appropriate electrolytic machining module (2) and electrolytic de-electrolytic machining module (3) according to the actual processing requirements and install them on the tool cathode (1); The assembled modular electrolytic discharge-electrolytic milling tool is connected to the spindle of the CNC machine tool through a fixture. The electrolyte flow channel inside the tool cathode (1) is connected to the electrolyte pipe held by the machine tool spindle. The tool cathode (1) is connected to the negative terminal of the machining power supply. The workpiece (7) to be processed is clamped on the machine tool working platform and connected to the positive terminal of the processing power supply; Adjust the relative position of the machining tool and the workpiece (7) so that the machining tool is directly above the starting point of the workpiece machining; Open the electrolyte supply valve, and the electrolyte is sprayed onto the surface of the workpiece (7) through the electrolyte flow channel inside the tool cathode (1); While turning on the machining power, control the tool cathode to feed downwards for machining. After reaching the specified depth of cut, control the tool to feed horizontally along the preset trajectory to perform milling. During the processing, the electrolytic discharge machining module (3) is located at the foremost end of the tool cathode in the milling direction, followed by the electrolytic machining module (2) and the automatic sealing device. Since the tilt angle of the end face of the electrolytic discharge machining module (3) is greater than that of the end face of the electrolytic machining module (2), the gap between the end face of the electrolytic machining module (2) and the workpiece (7) is greater than that between the end face of the electrolytic discharge machining module (3) and the workpiece (7). Under the same anode-cathode potential difference, the electrolytic discharge machining module (3) and the workpiece (7) have a higher electric field strength due to the smaller gap. Since the electric field strength threshold for the discharge effect is higher than that for the electrolytic effect, the intensity and area of ​​the discharge and electrolytic effects can be controlled. The workpiece (7) is first rapidly removed by electrolytic discharge machining, and then the surface recast layer defects are removed by electrolytic machining, thereby achieving high-efficiency and high-surface-quality machining. The automatic sealing device constrains the flow of electrolyte, so that the electrolyte flows through the machining gap between the electrolytic machining module (2), the electrolytic discharge machining module (3) and the surface of the workpiece (7) after being ejected from the flow channel, and the electrolyte flow rate is greatly increased by the back pressure effect. The rapid flow of electrolyte can break the plasma arc between the electrolytic discharge machining module (3) and the workpiece (7) in time, preventing the continuous arc from burning the tool and the surface of the workpiece (7). The rapid flow of electrolyte can also discharge the machining products in time, avoiding the machining products from blocking the machining gap and causing a short circuit.

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