Combined type drilling electrochemical machining electrode and electrode array

Abstract

According to the combined type drilling electrolytic machining electrode and the electrode array provided by the invention, uniform distribution and effective washing of electrolyte in a machining area are realized by limiting parameters of a water outlet hole of an electrode tip and an insulating sleeve, optimizing the structural size of an electrode main body and a flow guide interface and combining layered machining and a dynamic parameter adjustment strategy; the accumulation phenomenon of electrolytic products is obviously reduced, and the machining precision and the surface quality are improved; the electrode array is matched with the independent control module and the multi-channel distributor, synchronous and efficient multi-hole machining is achieved, and the multi-hole synchronous machining device is suitable for high-precision batch production scenes and has the advantages of being reasonable in structure, flexible to control and wide in applicability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrochemical machining, in particular to a combined drilling electrolytic machining electrode and electrode array. BACKGROUND

[0002] Electrolytic machining is a technology for realizing metal material forming by using the principle of electrochemical anode dissolution, which has the advantages of no tool wear, no material hardness limitation, no residual stress, etc., and is widely used in the machining of aero-engine blades, micro-holes, deep holes and complex cavities.

[0003] Traditional electrolytic machining electrodes mostly adopt a monolithic structure, and the electrolyte enters the machining area through the internal or external flow channel of the electrode. However, when machining deep holes or complex holes, as the electrode penetrates deeper, the electrolyte flow path increases, the flow rate and flow velocity decrease, resulting in accumulation of electrolytic products in the machining area, uneven distribution of electric field, and further causing problems such as decreased machining accuracy, increased hole wall roughness, and even short-circuit burning. There are existing technologies that use a hollow electrode combined with a lateral drainage groove, such as the cathode structure with a spiral drainage groove and a side insulation layer proposed in Chinese patent CN103273152A. Although this design improves the uniformity of the flow field to some extent, the drainage groove is prone to clogging, and the insulation layer is prone to falling off under high speed for a long time. Moreover, the internal flow channel structure of the electrode and the machining parameters are not systematically optimized, making it difficult to meet the needs of high-precision and high-efficiency batch machining. In addition, the existing electrode array lacks independent control and dynamic adjustment mechanism when machining multiple holes simultaneously, resulting in poor machining consistency and difficult to control workpiece deformation.

[0004] Therefore, how to optimize the key component parameters and the machining process while retaining the combined structure of the electrode to achieve uniform electrolyte supply and stable and controllable machining process has become a technical problem to be solved in the field. SUMMARY

[0005] The purpose of the present application is to provide a combined drilling electrolytic machining electrode and electrode array to solve the problems existing in the prior art.

[0006] To achieve the above purpose, the present application provides the following solutions: The present application provides a combined drilling electrolytic machining electrode, comprising: The electrode body is a hollow tubular structure, with an outer diameter of 3-10 mm, an inner diameter of 1.5-5 mm, and a length-diameter ratio not greater than 10:1; The electrode head is detachably connected to the bottom of the electrode body, and the surface thereof is provided with a plurality of water outlets, the diameter of the water outlet is 0.1-0.5 mm, the hole spacing is 1-3 mm, and the water outlets are distributed in a spiral or matrix shape; An insulating sleeve is wrapped on the lower outer wall of the electrode body, and the thickness of the insulating sleeve is 0.5-2mm; A reference seat is arranged on the middle part of the electrode body and is drivingly connected to the electrode body through a rotating motor; A conductive part is rotatably sleeved on the upper lateral wall of the electrode body and is in conduction with the electrode body; A water guide joint is connected with the top of the electrode body and is screwed with an electrolyte pipe.

[0007] Preferably, the material of the electrode body and the electrode head is stainless steel.

[0008] Preferably, the material of the insulating sleeve is polytetrafluoroethylene or ceramic.

[0009] Preferably, the material of the conductive part is pure copper, and the contact resistance is less than 0.01Ω.

[0010] The application also provides an electrode array, which comprises a linear base on which a plurality of the combined drilling electrolytic machining electrodes are arranged.

[0011] Preferably, the linear base is integrated with a multi-way electrolyte distributor and an independent control module.

[0012] The application also provides an electrolytic drilling machining method using the combined drilling electrolytic machining electrode, which comprises the following steps: S1. The combined drilling electrolytic machining electrode is installed on a machine tool lifting main shaft, and the perpendicularity is calibrated, and the error is less than or equal to 0.02mm / m; S2. The stroke of the combined drilling electrolytic machining electrode is set to 0.1-0.5mm / step, the rotation period is 5-10 seconds of rotation and 0.5-1 second of pause, the electrolyte flow is 5-20L / min, the flow rate is 2-6m / s, the pressure is 0.5-3MPa, the current density is 10-50A / cm 2 , the voltage is 5-20V, the pulse frequency is 100-1000Hz, and the duty cycle is 50-80%; S3. The electrolyte circulation system of the machine tool is started, and the preheating temperature is 20-40℃, and the alignment is performed, and the error is less than or equal to 0.05mm; S4. The electrolyte is passed first, and then the power is passed, and the delay time is 0.1-0.5 seconds; S5. The combined drilling electrolytic machining electrode is lowered by the lifting main shaft, the electrode head sprays electrolyte, and the electrode body rotates to perform layered machining, and the combined drilling electrolytic machining electrode is raised by 0.1-0.2mm after each 0.5-1mm depth of machining, and the process is continued for 2-5 seconds; S6. After the machining is completed, the power is turned off first, then the liquid is stopped, and the machining area is flushed after a delay of 0.5-1 seconds.

[0013] Preferably, in step S5, the electrolyte pressure is increased by 0.1 MPa for each 10 mm increase in machining depth.

[0014] The present application has the following beneficial technical effects relative to the prior art: The combined drilling electrolytic machining electrode and electrode array provided by the present application realize uniform distribution and effective flushing of the electrolyte in the machining area by limiting the water outlet hole parameters of the electrode head, the insulating sleeve, optimizing the structure size of the electrode body and the flow guide interface, and combining the layered machining and dynamic parameter adjustment strategy, significantly reducing the accumulation of electrolytic products, and improving the machining precision and surface quality; the electrode array cooperates with the independent control module and the multi-way distributor to realize synchronous and efficient machining of multiple holes, which is suitable for high-precision batch production scenarios, and has the characteristics of reasonable structure, flexible control and wide applicability. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 The combined drilling electrolytic machining electrode structure provided by the present application is shown in the figure; Figure 2 The electrode array structure provided by the present application is shown in the figure; Figure 3 Another electrode array structure provided by the present application is shown in the figure; In the figure: 1: electrode body, 2: electrode head, 3: insulating sleeve, 4: reference seat, 5: conductive part, 6: water guide connector, 7: rotary motor, 8: linear base. DETAILED DESCRIPTION

[0017] In the present application, the terms "connection" and "coupling" include direct and indirect connections (couplings) unless otherwise specified. In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0018] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0019] 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 only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The purpose of this invention is to provide a combined drilling electrolytic machining electrode and electrode array to solve the problems existing in the prior art.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1: like Figure 1 As shown, the present invention provides a combined drilling electrolytic machining electrode, comprising an electrode body 1, an electrode head 2, an insulating sleeve 3, a reference base 4, a conductive component 5, a water-conducting connector 6, and a rotary motor 7.

[0023] Specifically, the electrode body 1 is a hollow tubular structure made of electrolytically corrosion-resistant stainless steel. Its outer diameter is preferably 5 mm, its inner diameter is preferably 2.5 mm, and its length-to-diameter ratio is controlled at 8:1 to ensure low electrolyte flow resistance and sufficient structural rigidity. The internal through-holes of the electrode body 1 are mirror-polished with a surface roughness Ra≤0.4μm to reduce flow resistance.

[0024] Furthermore, the electrode head 2 is detachably installed at the bottom end of the electrode body 1 via a threaded connection or quick-release buckle. Any method that enables quick connection falls within the scope of this invention. It can be designed as a spherical, conical, or planar structure depending on the shape of the machining hole. The surface of the electrode head 2 is provided with spirally distributed water outlet holes with a diameter of 0.2 mm and a spacing of 2 mm. This arrangement ensures a uniform flow field of electrolyte within the machining area. Of course, the shape of the water outlet holes can also be varied according to the depth and shape of the machined hole.

[0025] Furthermore, the insulating sleeve 3 is made of polytetrafluoroethylene (PTFE) with a thickness of 1 mm, and is fixed to the lower part of the electrode body 1 by thermoforming. This segmented structure effectively prevents stray current corrosion on the sidewalls and allows the electrolyte to flow moderately within the gaps, avoiding the formation of dead zones.

[0026] Furthermore, the reference base 4 is made of high-strength aluminum alloy and is fixed to the machine tool lifting spindle by bolts. The rotary motor 7 is installed on the reference base 4, thereby driving the electrode body 1 to rotate.

[0027] Furthermore, the conductive component 5 is made of pure copper and maintains a dynamic electrical connection with the electrode body 1 through a spring contact structure, with a measured contact resistance of 0.008Ω.

[0028] Furthermore, the water guide connector 6 is threaded to the upper end of the electrode body 1 and is equipped with a double-lip fluororubber sealing ring, which can withstand a working pressure of 3MPa without leakage.

[0029] Example 2: For applications requiring batch processing of multiple holes, such as Figures 2-3 As shown, the present invention also provides an electrode array embodiment. The array consists of a linear base 8 and a plurality of the above-described electrode modules. The linear base 8 is made of 304 stainless steel and its surface is anodized.

[0030] As an improvement, the linear base 8 integrates a multi-channel electrolyte distributor, with the flow deviation of each branch controlled within ±5%. It is also equipped with an independent control module based on PLC, which can independently program the rotation speed and feed rate of each electrode.

[0031] The electrodes are arranged in a rectangular array on the base, and the spacing can be adjusted within the range of 5-20mm. By changing the size and shape of the reference base, the electrodes can be aligned one by one with the deep hole to be processed.

[0032] Example 3: This embodiment provides an electrolytic drilling method, which is implemented according to the following steps: First, the electrode is installed and calibrated. The electrode is fixed to the machine tool spindle using reference base 4, and the perpendicularity is checked with a dial indicator to ensure the error is ≤0.02mm / m. Next, machining parameters are set in the CNC system. The electrode feed rate is set to 0.3mm / step, using an intermittent motion mode of 8 seconds rotation followed by 0.8 seconds pause. The electrolyte (15% NaNO3 solution) flow rate is controlled at 12L / min, the initial system pressure is set to 1.2MPa, and a pulse power supply mode is used with a current density of 30A / cm². 2 Voltage 12V, pulse frequency 500Hz, duty cycle 60%.

[0033] Before processing, the electrolyte circulation system is activated, and the electrolyte temperature is stabilized at 25±2℃ via a heat exchanger. A vision alignment system ensures that the positioning error between the electrode and the workpiece is ≤0.03mm. At the start of processing, the electrolyte supply is turned on, and after a 0.3-second delay, the power is switched on. The lifting spindle lowers the electrode at a speed of 0.1mm / s. During processing, a layered strategy is implemented: after each 0.8mm depth processed, the electrode automatically rises 0.15mm, holding for 3 seconds to allow for the discharge of electrolytic products. For every 10mm increase in processing depth, the control system automatically increases the electrolyte pressure by 0.1MPa, up to a maximum of 3MPa. After processing, the power is switched off, and after a 0.8-second delay, the electrolyte supply is stopped. Finally, the processed area is rinsed with deionized water for 15 seconds.

[0034] In Example 1, this method was used to machine a 1mm diameter deep hole in a 304 stainless steel plate, with a hole depth of 10mm. The measured hole diameter tolerance was ±0.015mm, the hole wall surface roughness Ra was 0.8μm, and there was no taper error. Compared with the traditional integral electrode machining results, the machining efficiency was increased by 40%, and the electrode life was extended by more than 3 times.

[0035] In Example 2, this method utilizes an electrode array to simultaneously process nine holes with a diameter of 2mm, with a spacing of 10mm between each hole. After processing, the positional error of each hole was ≤0.05mm, the depth consistency error was ≤0.02mm, and no thermal deformation was observed in the workpiece. This demonstrates that the present invention effectively solves the technical challenges of uneven electrolyte distribution and difficult product discharge in deep hole machining through structural parameter optimization and precise control of the machining process.

[0036] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0037] It should be noted that the components mentioned in the above embodiments are all general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0038] This invention has illustrated its principles and implementation methods using specific examples. The descriptions of these embodiments are merely illustrative of the method and its core ideas; furthermore, those skilled in the art will recognize that modifications may be made to the specific implementation methods and application scope based on the principles of this invention. Therefore, the content of this specification should not be construed as limiting the invention.

Claims

1. A combined drilling electrolytic machining electrode, characterized in that, include: Electrode body (1), the electrode body (1) is a hollow tubular structure with an outer diameter of 3-10 mm, an inner diameter of 1.5-5 mm, and a length-to-diameter ratio of no more than 10:1; Electrode head (2), the electrode head (2) is detachably connected to the bottom of the electrode body (1), and its surface is provided with multiple water outlet holes, the diameter of the water outlet holes is 0.1-0.5mm, the hole spacing is 1-3mm, and they are distributed in a spiral or matrix shape; An insulating sleeve (3) is wrapped around the lower outer side wall of the electrode body (1) and has a thickness of 0.5-2 mm. Reference base (4), the reference base (4) is disposed in the middle of the electrode body (1) and is connected to the electrode body (1) by a rotary motor (7); Conductive element (5), the conductive element (5) is rotatably sleeved on the upper side wall of the electrode body (1) and is in communication with the electrode body (1); Water guide connector (6) is connected to the top of the electrode body (1) and screwed into the electrolyte pipe.

2. The combined drilling electrolytic machining electrode according to claim 1, characterized in that, The electrode body (1) and the electrode head (2) are made of stainless steel.

3. The combined drilling electrolytic machining electrode according to claim 1, characterized in that, The insulating sleeve (3) is made of polytetrafluoroethylene or ceramic.

4. The combined drilling electrolytic machining electrode according to claim 1, characterized in that, The conductive component (5) is made of pure copper and has a contact resistance of less than 0.01Ω.

5. An electrode array, characterized in that, It includes a linear base (8), on which a plurality of combined drilling electrolytic machining electrodes as described in any one of claims 1-4 are arrayed and mounted.

6. The electrode array according to claim 5, characterized in that, The linear base (8) integrates a multi-channel electrolyte distributor and an independent control module.

7. An electrolytic drilling method using the combined electrolytic drilling electrode as described in any one of claims 1-4, characterized in that, Includes the following steps: S1. Install the combined drilling electrolytic machining electrode on the machine tool lifting spindle and perform verticality calibration, with an error ≤0.02mm / m; S2. Set the stroke of the combined drilling electrolytic machining electrode to 0.1-0.5 mm / step, the rotation cycle to 5-10 seconds followed by a 0.5-1 second pause, the electrolyte flow rate to 5-20 L / min, the flow velocity to 2-6 m / s, the pressure to 0.5-3 MPa, and the current density to 10-50 A / cm². 2 The voltage is 5-20V, the pulse frequency is 100-1000Hz, and the duty cycle is 50-80%. S3. Start the machine tool's electrolyte circulation system, preheat to 20-40℃, and perform alignment, with an error ≤0.05mm; S4. Apply the electrolyte first, then apply the current, with a delay time of 0.1-0.5 seconds; S5. The lifting spindle drives the combined drilling electrolytic machining electrode to descend, the electrode head (2) sprays electrolyte, and at the same time the electrode body (1) rotates to perform layered processing. After each processing depth of 0.5-1mm, the combined drilling electrolytic machining electrode rises back by 0.1-0.2mm, lasting for 2-5 seconds. S6. After processing is completed, first turn off the power and then stop the liquid, with a delay of 0.5-1 second, and then rinse the processed area.

8. The electrolytic drilling method according to claim 7, characterized in that, In step S5, the electrolyte pressure increases by 0.1 MPa for every 10 mm increase in processing depth.

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