An involute internal spline self-lubricating tooth surface electrolytic machining device and method

Abstract

This invention provides an electrolytic machining apparatus for self-lubricating involute internal splines, comprising a gear-making cathode assembly, a tooth-surface microgroove machining cathode assembly, a cathode connector, and a workpiece blank fixing structure. One end of the gear-making cathode assembly / tooth-surface microgroove machining cathode assembly is connected to the cathode connector, and the other end of the cathode connector is connected to the negative terminal of a power supply. The workpiece blank is installed within the workpiece blank fixing structure. Electrolyte flows through the gap between the workpiece blank and the gear-making cathode assembly / tooth-surface microgroove machining cathode assembly, and the gear-making cathode assembly / tooth-surface microgroove machining cathode assembly can move along the axis of the workpiece blank. This invention also provides a method for electrolytic machining of self-lubricating involute internal splines. This invention uses a single set of tooling for both gear making and tooth-surface microgroove machining. After gear making is completed, only the tooth-surface microgroove cathode assembly needs to be replaced, improving the positioning accuracy and replacement efficiency of the involute internal spline, and improving the frictional performance of the involute internal spline.

Description

Technical Field

[0001] This invention belongs to the field of electrolytic machining technology, specifically relating to an electrolytic machining device and method for self-lubricating tooth surfaces of involute internal splines. Background Technology

[0002] Involute internal splines rely on the meshing of teeth to transmit torque and load. Due to cyclic contact stress and frictional resistance, the tooth surface is prone to failure modes such as tooth breakage, pitting, wear, and scuffing, thereby reducing important performance characteristics such as system stability and reliability. In recent years, research on frictional contact has shifted from macroscopic to microscopic, using microstructures of specific shapes (surface textures) on the surfaces of relatively moving mechanical components to improve the frictional performance between moving components, mainly to reduce friction, adhesion, and wear. The introduction of surface textures provides a new approach to improving the frictional performance between mechanical components. Therefore, to solve the problem of increased frictional resistance affecting the transmission performance of involute internal splines during transmission, self-lubricating tooth surfaces can solve lubrication problems under certain working conditions. The key step in machining self-lubricating tooth surfaces for involute internal splines is to complete the machining of the involute internal spline itself, followed by machining microgrooves on the tooth surface.

[0003] In existing technologies, involute internal splines are generally machined using gear shaping. However, after heat treatment, the splines are prone to deformation, resulting in taper between the bar spacing and flared openings at the orifices. Currently, this taper cannot be repaired, and parts are frequently scrapped due to exceeding tolerances. Furthermore, when machining on high-strength steel, problems often arise such as the gear shaping tool being unable to penetrate, and the machined groove width being flared and the groove bottom having taper. Wire EDM is the only option, but it introduces a remelted layer, posing a potential quality risk. Secondly, considering that the surface to be machined is an involute tooth surface, conventional methods struggle to machine the required microgrooves on this complex surface. Electrolytic machining technology offers unique advantages. This process removes excess material based on the principle of electrochemical anodic solvent removal, and there is no contact between the workpiece and the tool cathode during machining. Therefore, electrolytic machining is a more ideal method for self-lubricating tooth surface machining. Based on the above, this invention provides an electrolytic machining apparatus and method for self-lubricating tooth surfaces of involute internal splines, to improve the machining accuracy and frictional performance of involute internal splines. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that the increased frictional resistance during transmission of involute internal splines affects the performance of the transmission system. This invention provides a combined electrolytic machining device and method for self-lubricating tooth surfaces of involute internal splines, which solves the problems of heat treatment deformation and tooth surface wear of involute internal splines, and can improve the machining accuracy and frictional performance of involute internal splines.

[0005] To achieve the above technical objectives, the present invention adopts the following technical solution:

[0006] (I) This invention provides an electrolytic machining device for self-lubricating involute internal spline tooth surfaces, comprising a tooth-making cathode assembly, a tooth surface microgroove machining cathode assembly, a cathode connector, and a workpiece blank fixing structure; one end of the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly is detachably connected to the cathode connector, and the other end of the cathode connector is connected to the negative terminal of the power supply; a workpiece blank is detachably installed in the workpiece blank fixing structure, and the workpiece blank is connected to the positive terminal of the power supply; a machining gap is provided between the workpiece blank and the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly, and an electrolyte flows through the machining gap, and the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly can move along the axis of the workpiece blank.

[0007] Furthermore, the workpiece blank has a hollow structure, and the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly is distributed in the cavity of the workpiece blank and can move along the axis of the workpiece blank.

[0008] Furthermore, the workpiece blank fixing structure includes a base and a bushing; the base has a mounting groove adapted to the workpiece blank at its center, the workpiece blank is placed in the mounting groove, and the base is connected to the positive terminal of the power supply; the bushing has a fixing groove adapted to the workpiece blank at its lower part, and the bushing is installed above the workpiece blank through the fixing groove; a gap is left between the lower surface of the bushing and the upper surface of the base.

[0009] Furthermore, the device is also provided with an electrolyte guiding cavity; the electrolyte guiding cavity is a hollow structure and is fixedly installed above the bushing; the electrolyte guiding cavity is provided with an electrolyte rectification area and an electrolyte output channel, the electrolyte rectification area is connected to the processing gap of the workpiece blank and the tooth machining cathode assembly / tooth surface microgroove machining cathode assembly, and the electrolyte output channel is connected to the electrolyte rectification area.

[0010] Furthermore, the cathode connector includes a cathode chuck and a cathode connecting rod; the cathode chuck is connected to the negative terminal of the power supply; the top end of the cathode connecting rod is fixedly connected to the cathode chuck, and the bottom end is fixedly connected to the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly; an electrolyte input channel is provided inside the cathode chuck, and an electrolyte transmission channel is provided inside the cathode connecting rod; the electrolyte input channel communicates with the electrolyte transmission channel, and the electrolyte transmission channel communicates with the machining gap between the workpiece blank and the tooth-making cathode assembly / tooth surface microgroove machining cathode assembly.

[0011] Furthermore, the device is also provided with an insulating connecting rod, the insulating connecting rod having a cavity inside that is adapted to the cathode connecting rod, the insulating connecting rod being tightly fitted to the outer surface of the cathode connecting rod; a sealing groove is provided on the upper surface of the cathode connecting rod, and a first sealing ring is provided in the sealing groove.

[0012] Furthermore, the outer wall of the insulating connecting rod is provided with a sealing groove, which is distributed along the outer circumference of the insulating connecting rod, and a second sealing ring is provided in the sealing groove.

[0013] Furthermore, the tooth surface microgroove machining cathode assembly includes a central part and several cathode teeth. The cathode teeth are detachably mounted on the outer surface of the central part. Several microstructure bosses are provided on the tooth surface of the cathode teeth. The non-tooth surface part of the cathode teeth is provided with a cathode tooth insulating sleeve. The number of cathode teeth is the same as the number of involute spline teeth, and the cathode height is equal to the involute spline mating length.

[0014] Furthermore, an upper guide member is provided between the cathode tooth and the upper edge of the center member, and a lower guide member is provided between the cathode tooth and the lower edge of the center member.

[0015] Furthermore, both the upper and lower flow guides are made of plastic, which can prevent the workpiece's machining accuracy and surface quality from being reduced due to stray corrosion during processing. In addition, the upper and lower flow guides can improve the stability of the flow field during processing.

[0016] Furthermore, the tooth-making cathode assembly includes a central component and a plurality of processing teeth, which are distributed on the outer surface of the central component; the processing teeth have a variable cross-section structure, that is, the cross-sectional shape of the processing teeth remains unchanged, and the cross-sectional area gradually decreases along the direction toward the edge of the central component; the processing teeth are provided with processing blades, and the ends of the processing blades are provided with polishing blades; the edge of the central component is provided with an insulating cover.

[0017] Furthermore, the machining teeth have an involute tooth shape.

[0018] Furthermore, the device is also provided with guide sections; the number of guide sections is the same as the number of machining teeth, and the guide sections are installed on the outer surface of the center part; the structure of the guide sections is the same as the structure of the machining teeth, and the guide sections and machining teeth are distributed in a mirror image with the polishing blade as the axis.

[0019] Furthermore, the groove design factors for the self-lubricating tooth surface of the involute internal spline include four elements: groove depth H, groove area A, groove width L, and groove type. The groove depth H of the self-lubricating tooth surface of the involute internal spline is determined by the thickness of the involute internal spline tooth. The groove area A of the self-lubricating tooth surface of the involute internal spline is determined by the surface area of ​​the involute internal spline tooth. The width L of the involute internal spline groove is determined by the groove depth. The groove type of the self-lubricating tooth surface of the involute internal spline is determined by the friction coefficient f and the temperature rise ΔT at the interface.

[0020] (II) The present invention also provides a processing method for an electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines, based on the apparatus described above, comprising the following steps:

[0021] Align and fix the cathode connector to the machine tool spindle horizontally. After precisely positioning the workpiece blank fixing structure and the cathode connector, fix them on the machine tool's horizontal operating table. Fix the gear-making cathode assembly to the cathode connector. Embed the workpiece blank into the groove inside the workpiece blank fixing structure. Start the machine tool, and the gear-making cathode assembly feeds relative to the workpiece blank to perform tooth profile machining. After the tooth profile machining is completed, disassemble the gear-making cathode assembly. Fix the tooth surface microgroove machining cathode assembly to the cathode connector. Through electrolysis, perform tooth surface microgroove machining on the tooth surface of the workpiece blank.

[0022] Furthermore, the step of embedding the workpiece blank into the groove provided in the workpiece blank fixing structure specifically includes: embedding the workpiece blank into the cylindrical groove provided in the base, then placing the bushing above the workpiece blank, axially positioning the upper surface of the base and the lower surface of the bushing, and using hexagon socket screws for detachable fixing connection; wherein, a certain distance is left between the lower surface of the bushing and the upper surface of the base to prevent the workpiece from being over-positioned.

[0023] Beneficial effects

[0024] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0025] 1. This invention uses a three-dimensional forming cathode for tooth machining, characterized by a variable cross-section machining blade and a polishing blade; during the machining process, the variable cross-section machining blade quickly removes excess material from the workpiece, allowing the tooth shape to be formed quickly, and finally the polishing blade polishes the tooth surface, improving the machining accuracy and surface quality of the tooth surface.

[0026] 2. This invention uses electrolytic machining technology to process microgrooves on the complex curved surface of the involute internal spline. By reducing friction, adhesion and wear, it improves the friction performance of the moving components and avoids failure modes such as tooth surface breakage, pitting and wear of the involute internal spline.

[0027] 3. The present invention uses a set of tooling for the gear making and tooth surface microgroove processing device. After the gear making is completed, only the tooth surface microgroove cathode assembly needs to be replaced, which improves the positioning accuracy of the involute spline and the replacement efficiency.

[0028] 4. This invention employs electrolytic machining technology for machining the self-lubricating tooth surface of involute internal splines. This method removes material in the form of ions, is not limited by the properties of the workpiece material, can process various difficult-to-cut metal materials, and has no mechanical cutting force on the workpiece surface. Therefore, no residual stress or deformation will be generated on the workpiece surface.

[0029] 5. This invention adopts full-tooth synchronous processing for tooth making and tooth surface micro-groove processing. The number of cathode teeth is the same as the number of workpiece teeth, and the cathode teeth correspond to the workpiece tooth grooves. During the processing, the tool cathode and the workpiece anode never come into contact, leaving a certain processing gap, and the tool cathode is not damaged. Attached Figure Description

[0030] Figure 1 This is a simplified structural diagram of the electrolytic machining device for microgrooving the involute internal spline tooth surface according to the present invention.

[0031] Figure 2 This is a cross-sectional view of the electrolytic machining apparatus for microgrooving the involute internal spline tooth surface according to the present invention.

[0032] Figure 3 This is a simplified structural diagram of the toothed microgroove cathode assembly of the present invention;

[0033] Figure 4 This is a simplified structural diagram of the cathode assembly for electrolytic machining of teeth according to the present invention;

[0034] Figure 5 This is a simplified diagram of a single cathode structure for electrolytic machining of microgrooves on tooth surfaces according to the present invention.

[0035] Figure 6 A three-dimensional model of the self-lubricating tooth surface of an involute internal spline;

[0036] Figure 7 This is a cross-sectional view of the flow cavity caused by the electrolyte.

[0037] Figure 8 This is a perspective view of the cathode assembly for electrolytic machining of teeth according to the present invention;

[0038] The labels in the attached diagram are:

[0039] 1. Electrolyte inlet channel; 2. Cathode connecting rod; 3. Insulating connecting rod; 4. Electrolyte guide cavity; 5. Bushing; 6. Base; 7. Cathode chuck; 8. Cathode assembly with microgrooved tooth surface; 8-1. Cathode tooth; 8-2. Cathode tooth insulating sleeve; 8-3. Upper guide component; 8-4. Lower guide component; 9. Workpiece blank; 10. Insulating ring; 11. Cathode assembly with toothed surface; 11-1. Guide section; 11-2. Machining blade; 11-3. Polishing blade; 11-4. Insulating cover; 12. First sealing ring; 13. Second sealing ring; 14. Electrolyte outlet channel; 15. Electrolyte rectification area. Detailed Implementation

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Example 1

[0042] Reference Figures 1-2 The present invention provides an electrolytic machining device for self-lubricating tooth surface of involute internal spline, comprising a tooth machining cathode assembly 11, a tooth surface microgroove machining cathode assembly 8, a cathode connector, and a workpiece blank fixing structure.

[0043] Specifically, the tooth-making cathode assembly 11 / tooth surface microgroove machining cathode assembly 8 is detachably connected to one end of the cathode connector, and the other end of the cathode connector is connected to the negative terminal of the power supply; a workpiece blank 9 is detachably installed in the workpiece blank fixing structure, and the workpiece blank 9 is connected to the positive terminal of the power supply; a machining gap is provided between the workpiece blank 9 and the tooth-making cathode assembly 11 / tooth surface microgroove machining cathode assembly 8, and electrolyte flows in the machining gap.

[0044] In this embodiment, the workpiece blank 9 has a hollow structure, and the tooth-making cathode assembly 11 / tooth surface microgroove machining cathode assembly 8 is distributed in the cavity of the workpiece blank 9 and can move along the axis of the workpiece blank 9.

[0045] In application, the tooth-making cathode assembly 11 is first connected to the cathode connector, and the tooth-making cathode assembly 11 is fed relative to the workpiece blank 9 to achieve tooth profile machining within the workpiece blank 9. After the tooth profile machining is completed, the tooth-making cathode assembly 11 is disassembled, and the tooth surface microgroove machining cathode assembly 8 is connected to the cathode connector. The tooth surface microgroove machining cathode assembly 8 is distributed in the hollow cavity of the workpiece blank 9, and a certain gap is left between the tooth surface microgroove machining cathode assembly 8 and the workpiece blank 9. The tooth surface microgroove machining cathode assembly 8 and the workpiece blank 9 remain relatively stationary. Through electrolysis, the machining of the tooth surface microgrooves on the workpiece blank 9 is achieved.

[0046] Example 2

[0047] The main structure of this embodiment is the same as that of embodiment 1. The difference is that the workpiece blank fixing structure is limited in this embodiment.

[0048] Specifically, refer to Figures 1-2 The workpiece blank fixing structure includes a base 6 and a bushing 5; the base 6 has a mounting groove adapted to the workpiece blank 9 at its center, the workpiece blank 9 is placed in the mounting groove, and the base 6 is connected to the positive terminal of the power supply; the bushing 5 has a fixing groove adapted to the workpiece blank 9 at its lower part, and the bushing 5 is installed above the workpiece blank 9 through the fixing groove; a certain gap is left between the lower surface of the bushing 5 and the upper surface of the base 6 to prevent the workpiece from being over-positioned.

[0049] In application, the workpiece blank 9 is embedded into the fixing groove in the center of the base 6. Then, the bushing 5 is placed on top of the workpiece blank 9, and the upper surface of the base 6 and the lower surface of the bushing 5 are axially positioned and detachably fixed using hexagon socket screws. During clamping, a certain distance is maintained between the lower surface of the bushing 5 and the upper surface of the base 6 to prevent the workpiece from being over-positioned.

[0050] Example 3

[0051] The main structure of this embodiment is the same as that of embodiment 2. The difference is that this embodiment also provides an electrolyte guiding cavity 4.

[0052] Specifically, refer to Figures 1-2 and Figure 7 The electrolyte guiding cavity 4 is a hollow structure and is fixedly installed above the bushing 5. The electrolyte guiding cavity 4 is provided with an electrolyte rectification area 15 and an electrolyte output channel 14. The electrolyte rectification area 15 is connected to the processing gap between the workpiece blank 9 and the tooth machining cathode assembly 11 / tooth surface microgroove machining cathode assembly 8. The electrolyte output channel 14 is connected to the electrolyte rectification area 15.

[0053] In this embodiment, the electrolyte guide cavity 4 is made of plastic to reduce the overall weight of the tooling.

[0054] In application, the electrolyte that completes the electrochemical reaction in the gap between the workpiece blank 9 and the tooth machining cathode assembly 11 / tooth surface microgroove machining cathode assembly 8 first flows into the electrolyte rectification area 15, then enters the electrolyte output channel 14, and finally flows out of the device through the electrolyte output channel 14.

[0055] Example 4

[0056] The main structure of this embodiment is the same as that of embodiment 3. The difference is that the structure of the cathode connector is limited in this embodiment.

[0057] Specifically, refer to Figures 1-2 The cathode connector includes a cathode chuck 7 and a cathode connecting rod 2. The cathode chuck 7 is connected to the negative terminal of the power supply. The top end of the cathode connecting rod 2 is fixedly connected to the cathode chuck 7, and the bottom end is fixedly connected to the tooth-making cathode assembly 11 / tooth surface microgroove machining cathode assembly 8. An electrolyte input channel 1 is provided inside the cathode chuck 7, and an electrolyte transmission channel is provided inside the cathode connecting rod 2. The electrolyte input channel 1 communicates with the electrolyte transmission channel, and the electrolyte transmission channel communicates with the machining gap between the workpiece blank 9 and the tooth-making cathode assembly 11 / tooth surface microgroove machining cathode assembly 8. A sealing groove is provided on the upper surface of the cathode connecting rod 2, and a first sealing ring 12 is provided inside the sealing groove.

[0058] In this embodiment, an insulating connecting rod 3 is also provided. The insulating connecting rod 3 has a cavity inside that is adapted to the cathode connecting rod 2. The insulating connecting rod 3 is tightly fitted to the outer surface of the cathode connecting rod 2, and the insulating connecting rod 3 can prevent the outer surface of the cathode connecting rod 2 from being affected by stray corrosion during processing. The outer wall of the insulating connecting rod 3 is provided with a sealing groove, which is distributed along the outer circumference of the insulating connecting rod 3. A second sealing ring 13 is embedded in the sealing groove to prevent electrolyte from splashing outward from the gap during processing, thereby affecting the stability of the processing.

[0059] In application, external electrolyte flows in through the electrolyte inlet channel 1 of the cathode chuck 7, and then flows through the electrolyte transmission channel into the machining gap between the workpiece blank 9 and the tooth machining cathode assembly 11 / tooth surface microgroove machining cathode assembly 8. This fills the gap between the workpiece blank 9 and the tooth machining cathode assembly 11 / tooth surface microgroove machining cathode assembly 8 with electrolyte and participates in the electrochemical reaction, ensuring the smooth completion of electrochemical machining. After undergoing the electrochemical reaction in the machining area, the electrolyte flows out from the electrolyte outlet channel 14 of the electrolyte guide cavity 4.

[0060] Example 5

[0061] The main structure of this embodiment is the same as that of embodiment 4. The difference is that the structure of the cathode assembly 8 with microgroove tooth surface processing is limited in this embodiment.

[0062] Specifically, refer to Figure 3 and Figure 5 The toothed microgroove cathode assembly 8 includes a central component and several cathode teeth 8-1. The cathode teeth 8-1 are detachably mounted on the outer surface of the central component. Several microstructure bosses are provided on the tooth surface of the cathode teeth 8-1. Cathode tooth insulating sleeves 8-2 are provided on the non-tooth surface of the cathode teeth 8-1. The number of cathode teeth 8-1 is the same as the number of involute spline teeth, and the cathode height is equal to the involute spline mating length.

[0063] In this embodiment, an upper guide member 8-3 is provided between the cathode tooth 8-1 and the upper edge of the central member, and a lower guide member 8-4 is provided between the cathode tooth 8-1 and the lower edge of the central member. The upper guide member 8-3 and the lower guide member 8-4 can be configured as inclined structures to facilitate the flow of electrolyte.

[0064] In this embodiment, both the upper guide member 8-3 and the lower guide member 8-4 are made of plastic, which can prevent the workpiece's processing accuracy and surface quality from being reduced due to stray corrosion during processing. Furthermore, the upper guide member 8-3 and the lower guide member 8-4 can improve the stability of the flow field during processing.

[0065] Example 6

[0066] The main structure of this embodiment is the same as that of embodiment 5. The difference is that the structure of the tooth-making cathode assembly 11 is limited in this embodiment.

[0067] Specifically, refer to Figure 4 and Figure 8 The tooth-processing cathode assembly 11 includes a central component and processing teeth, which are integrally formed. The number of processing teeth is the same as the number of teeth on an involute spline. The axis of the processing teeth is parallel to the axis of the central component, and multiple processing teeth are evenly distributed circumferentially on the outer surface of the central component.

[0068] In this embodiment, the machining teeth are involute tooth structures with a constant cross-sectional shape, but the cross-sectional area gradually decreases towards the edge of the central part, i.e., the machining teeth are variable cross-section structures. The machining teeth are provided with machining blades 11-2 (the two outer surfaces of the machining teeth form machining blades 11-2). The machining blades 11-2 mainly perform rough machining on the workpiece blank 9, quickly removing large amounts of material and forming the tooth shape. The ends of the machining blades 11-2 are provided with polishing blades 11-3. After the tooth shape is formed, it is polished by the polishing blades 11-3, which also alleviate the flow field divergence problem near the formed cross-section while polishing. An insulating cover 11-4 is provided on the edge of the central part. The insulating cover 11-4 is interference-fitted with the machining blades 11-2, providing convenient connection and effective insulation for non-working surfaces.

[0069] In this embodiment, the device also includes a flow guide section 11-1; the number of flow guide sections 11-1 is the same as the number of machining teeth, and the flow guide sections 11-1 are installed on the outer surface of the center part; the structure of the flow guide section 11-1 is the same as the structure of the machining teeth, and the flow guide section 11-1 and the machining teeth are distributed in a mirror image with the polishing blade 11-2 as the axis. The flow guide section 11-1 can guide the flow during processing, improving problems such as unstable flow field that may be caused by complex workpiece structure and narrow channels, and improving the stability of the processing process. At the same time, the flow guide section 11-1 is made of insulating material and can be insulated.

[0070] Example 7

[0071] This embodiment provides a machining method for an electrolytic machining apparatus for self-lubricating involute internal spline tooth surfaces, based on the electrolytic machining apparatus for self-lubricating involute internal spline tooth surfaces described in Embodiment 6, and specifically includes the following steps:

[0072] Step 1: Start the precision electrolytic processing equipment, then start the heating system. Once the electrolyte temperature reaches 30°C, start the constant temperature system.

[0073] Step 2: After aligning the cathode chuck 7 with the machine tool spindle, use multiple hex socket screws to detachably and securely connect the cathode chuck 7 to the machine tool. Place the base 6 on the machine tool's horizontal operating table, and after precisely positioning it with the cathode chuck 7 through pin holes, use hex socket screws to fix the base 6 to the machine tool's horizontal operating table.

[0074] Step 4: Embed the insulating ring 10 into the bottom of the workpiece blank 9, and embed the workpiece blank 9 into the fixing groove set in the center of the base 6, ensuring that the outer surface of the workpiece blank 9 is in close contact with the inner surface of the fixing groove of the base 6, and that the lower surface of the workpiece blank 9 is in close contact with the bottom surface of the fixing groove of the base 6.

[0075] Step 5: Place the bushing 5 on top of the workpiece blank 9. Axially position the upper surface of the base 6 and the lower surface of the bushing 5, and use hex socket head cap screws to detachably fix them together, ensuring that the inner surface of the fixing groove of the bushing 5 is tightly fitted to the workpiece blank 9. During the clamping process, a certain distance is maintained between the lower surface of the bushing 5 and the upper surface of the base 6 to prevent the workpiece from being over-positioned axially.

[0076] Step 6: After each small part in the tooth-making cathode assembly 11 is angularly positioned through the pin holes, it is fixedly connected using hex socket screws; after the tooth-making cathode assembly 11 is installed, the insulating connecting rod 3 is tightly attached to the outer surface of the cathode connecting rod 2, and the tooth-making cathode assembly 11 is connected to the cathode connecting rod 2.

[0077] Step 7: After aligning the lower surface of the cathode chuck 7 using a dial indicator, insert the first sealing ring 12 into the sealing groove on the upper surface of the cathode connecting rod 2, and detachably fix the cathode connecting rod 2 to the cathode chuck 7 using hexagonal screws; then align the outer cylindrical surface of the cathode connecting rod 2 using a dial indicator. If a large verticality installation error is found, shims can be inserted into the two overlapping surfaces of the cathode chuck 7 and the cathode connecting rod 2 to reduce the installation error.

[0078] Step 8: Install the electrolyte guide cavity 4 on the upper end of the bushing 5, and insert the dried electrolyte inlet pipe into the electrolyte inlet channel 1 and the electrolyte outlet channel 14 respectively.

[0079] Step 9: Insert the second sealing ring 13 into the sealing groove provided in the insulating connecting rod 3 to prevent electrolyte from splashing outward from the gap during the processing, thereby affecting the stability of the processing;

[0080] Step 10: Connect the cathode chuck 7 to the negative terminal of the machine tool and connect the base 6 to the positive terminal of the machine tool power supply; check whether the equipment power supply and electrolyte filtration system and other components are normal.

[0081] Step 11: Set the electrolytic machining parameters and machining mode, and record the data; the gear-making cathode assembly 11 continues to feed along the axial direction of the workpiece blank 9 with the machine tool spindle. After completing the involute internal spline gear-making, the power is cut off, the machine tool spindle is raised a certain distance, the workpiece with completed gear-making is taken out, and it is rinsed with clean water.

[0082] Step 12: Measure the workpiece after tooth machining using a coordinate measuring machine, analyze the normal phase error between each point and the theoretical profile, and optimize the cathode and parameters until the machined tooth profile meets the design requirements.

[0083] Step 13: Disassemble the tooth machining cathode assembly 11 and install the tooth surface microgroove machining cathode assembly 8 with the cathode connecting rod 2. Through electrolysis, perform tooth surface microgroove machining on the tooth surface of the workpiece blank 9. In the tooth surface microstructure machining, the tool cathode does not generate feed motion, but only discharges.

[0084] Step 14: After processing, the processed sample is measured using a coordinate measuring machine, and the normal phase error between each point and the theoretical surface is analyzed. Through cathode optimization and parameter optimization, the processing requirements are met.

[0085] This invention provides a combined electrolytic machining device and method for self-lubricating involute internal splines. The electrolytic machining of involute internal splines achieves simultaneous machining of all teeth through a forming cathode and a planned cathode movement. The simultaneous forming process uses a three-dimensional forming cathode with the same number of cathode teeth as the workpiece teeth, and the cathode teeth correspond to the workpiece tooth grooves. The cathode movement trajectory is along the axial direction of the workpiece, achieving one-time forming of the involute internal spline. This results in high machining efficiency and a simple cathode movement trajectory, thus completing the machining of the involute internal spline tooth shape. Secondly, for the machining of microgrooves on the tooth surface, a cathode tooth with a microstructure boss is inserted into the central inner groove and then fixedly connected with an internal hexagonal screw. This completes the installation of the cathode assembly for microgrooving. During microgrooving, the tool cathode does not generate feed motion; it only performs electrical discharge machining. When machining microgrooves, both tooth forming and microgrooving share a single tooling set; only the cathode assembly needs to be replaced, improving the positioning accuracy and replacement efficiency of the involute internal spline.

[0086] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines, characterized in that, Includes a tooth-making cathode assembly (11), a tooth surface microgroove cathode assembly (8), a cathode connector, and a workpiece blank fixing structure; The cathode assembly (11) for tooth processing / the cathode assembly (8) for tooth surface microgroove processing is detachably connected to one end of the cathode connector, and the other end of the cathode connector is connected to the negative terminal of the power supply; a workpiece blank (9) is detachably installed in the workpiece blank fixing structure, and the workpiece blank (9) is connected to the positive terminal of the power supply. A machining gap is provided between the workpiece blank (9) and the tooth-making cathode assembly (11) / tooth surface microgroove machining cathode assembly (8), and electrolyte flows in the machining gap. The tooth-making cathode assembly (11) / tooth surface microgroove machining cathode assembly (8) can move along the axis of the workpiece blank (9). In application, the tooth-making cathode assembly (11) is first connected to the cathode connector, and the tooth-making cathode assembly (11) is fed relative to the workpiece blank (9) to realize the tooth shape processing in the workpiece blank (9); after the tooth shape processing is completed, the tooth-making cathode assembly (11) is disassembled, and the tooth surface micro-groove processing cathode assembly (8) is connected to the cathode connector. The tooth surface micro-groove processing cathode assembly (8) and the workpiece blank (9) remain relatively stationary. Through electrolysis, the micro-groove processing of the workpiece blank (9) is realized.

2. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 1, characterized in that, The workpiece blank fixing structure includes a base (6) and a bushing (5); The base (6) has a mounting groove at its center that is adapted to the workpiece blank (9). The workpiece blank (9) is placed in the mounting groove, and the base (6) is connected to the positive terminal of the power supply. The lower part of the bushing (5) is provided with a fixing groove that is adapted to the workpiece blank (9), and the bushing (5) is installed above the workpiece blank (9) through the fixing groove; There is a gap between the lower surface of the bushing (5) and the upper surface of the base (6).

3. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 2, characterized in that, An electrolyte flow channel (4) is also provided. The electrolyte guide cavity (4) is fixedly installed above the bushing (5); The electrolyte guiding cavity (4) is provided with an electrolyte rectification area (15) and an electrolyte output channel (14). The electrolyte rectification area (15) is connected to the workpiece blank (9) and the machining gap of the tooth machining cathode assembly (11) / tooth surface microgroove machining cathode assembly (8). The electrolyte output channel (14) is connected to the electrolyte rectification area (15).

4. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 1, characterized in that, The cathode connector includes a cathode clamp (7) and a cathode connecting rod (2). The top end of the cathode connecting rod (2) is fixedly connected to the cathode chuck (7), and the bottom end is fixedly connected to the tooth-making cathode assembly (11) / tooth surface micro-groove machining cathode assembly (8); An electrolyte input channel (1) is provided inside the cathode chuck (7), and an electrolyte transmission channel is provided inside the cathode connecting rod (2); the electrolyte input channel (1) is connected to the electrolyte transmission channel, and the electrolyte transmission channel is connected to the processing gap between the workpiece blank (9) and the tooth machining cathode assembly (11) / tooth surface microgroove machining cathode assembly (8).

5. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 4, characterized in that, An insulating connecting rod (3) is also provided. The insulating connecting rod (3) has a cavity inside that is adapted to the cathode connecting rod (2). The insulating connecting rod (3) is tightly attached to the outer surface of the cathode connecting rod (2). A sealing groove is provided on the upper surface of the cathode connecting rod (2), and a first sealing ring (12) is provided in the sealing groove.

6. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 5, characterized in that, The outer wall of the insulating connecting rod (3) is provided with a sealing groove, which is distributed along the outer circumference of the insulating connecting rod (3), and a second sealing ring (13) is provided in the sealing groove.

7. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 1, characterized in that, The toothed microgroove cathode assembly (8) includes a central part and several cathode teeth (8-1). The cathode teeth (8-1) are detachably mounted on the outer surface of the central part. Several microstructure bosses are provided on the tooth surface of the cathode teeth (8-1). The non-tooth surface part of the cathode teeth (8-1) is provided with cathode tooth insulating sleeves (8-2). An upper guide member (8-3) is provided between the cathode tooth (8-1) and the upper edge of the center member, and a lower guide member (8-4) is provided between the cathode tooth (8-1) and the lower edge of the center member.

8. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 1, characterized in that, The tooth-making cathode assembly (11) includes a central component and a plurality of processing teeth, the processing teeth being distributed on the outer surface of the central component; The cross-sectional area of ​​the machining teeth gradually decreases along the direction toward the edge of the central part. The machining teeth are provided with machining blades (11-2), and the ends of the machining blades (11-2) are provided with polishing blades (11-3). The edge of the central part is provided with an insulating cap (11-4).

9. The electrolytic machining apparatus for self-lubricating tooth surfaces of involute internal splines according to claim 8, characterized in that, A diversion section (11-1) is also provided. The number of the guide sections (11-1) is the same as the number of machining teeth, and the guide sections (11-1) are installed on the outer surface of the center part; The structure of the guide section (11-1) is the same as that of the machining teeth. The guide section (11-1) and the machining teeth are mirror images of each other with the polishing blade (11-2) as the axis.

10. A method of processing the apparatus for electrolytic machining of self-lubricating tooth surface of involute internal spline according to claim 1, characterized in that, Includes the following steps: Align and fix the cathode connector to the machine tool spindle horizontally. After accurately positioning the workpiece blank fixing structure and the cathode connector, fix it on the machine tool horizontal operating table. The cathode assembly (11) for tooth making is fixedly connected to the cathode connector, and the workpiece blank (9) is embedded in the groove provided in the workpiece blank fixing structure. Start the machine tool and feed the cathode assembly (11) relative to the workpiece blank to perform tooth profile machining. After the tooth profile machining is completed, the tooth machining cathode assembly (11) is disassembled, and the tooth surface microgroove machining cathode assembly (8) is fixedly connected to the cathode connector. Through electrolysis, tooth surface microgroove machining is performed on the tooth surface of the workpiece blank (9).

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