Ultrasonic vibration internal liquid electrochemical discharge-grinding processing device and tool changing method

Abstract

The present invention relates to the field of micro-machining technology, and in particular, provides an ultrasonic vibration internal liquid electrochemical discharge grinding processing device and a tool changing method. The method includes a processing device including an old tool holder, a new tool holder, an electric spindle, a spindle clamp, an auxiliary electrode, a processing workpiece, an electrolyte tank, a Hall current sensor, an automatic tool changing device; an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool changing operating system, and a position control system; wherein the tool holder includes a primary coil, a secondary coil, an ultrasonic transducer, a rotary liquid joint, and a tool electrode. The processing device integrates the three technologies of ultrasonic vibration, mechanical grinding, and external rotation and internal liquid through the ultrasonic transducer, the tool electrode, and the external liquid supply device. While ensuring processing efficiency, it improves the continuity and stability of processing, improves processing quality, and achieves high-quality, high-efficiency, and low-cost processing of processing materials.

Description

Technical Field

[0001] The present invention relates to the technical field of micro-machining, in particular to an ultrasonic vibration internal liquid electrochemical discharge-grinding processing device and a tool changing method, which are used for processing hard and brittle materials. Background Art

[0002] Hard and brittle materials possess characteristics such as high hardness, high wear resistance, and brittleness, enabling them to withstand harsh environments and high pressures, and exhibit excellent performance under high temperature and corrosive conditions. They play an important role in optics, electronics, fiber-optic communications, aerospace, and medical applications. However, due to their unique physical and chemical properties, they are prone to various defects such as surface microcracks and subsurface damage during processing, making processing difficult and resulting in low yield rates.

[0003] On the other hand, with the rapid development of electronic technology and the semiconductor industry, third-generation semiconductor materials such as silicon carbide are widely used in power electronics, high-frequency electronics, and optoelectronics. These materials have excellent electrical conductivity, high-temperature stability, and high power density, but their hardness and brittleness make them difficult to process.

[0004] Currently, the main processing methods for the above materials include ultrasonic machining, abrasive water jet machining, and laser machining. The cost of ultrasonic machining prefabricated forming tools is high, and the mechanical force during the machining process will also cause a large number of cracks in the material and tool wear. In addition, its machining accuracy is limited by the amplitude, making it difficult to achieve high-precision micro-hole machining. Abrasive water jet machining has low machining accuracy, easily forms gradients in thickness and depth, and has a short nozzle life, high noise level, and high equipment cost. In the process of deep small hole machining, ultrafast laser machining is not yet mature in terms of principles and processes. As the machining depth increases, polarization affects the beam transmission, resulting in a significant taper in the hole. The machining hole depth is difficult to control, and a recast layer is easily formed on the side wall. It is relatively sparse and has hollow gaps, which greatly affects its surface quality.

[0005] Plasma etching and chemical etching are other processing methods. However, plasma etching requires complex equipment, consumes a lot of energy, is costly, and causes severe pollution. Furthermore, the processing line width is large and the verticality is low, making it unsuitable for micromachining. Chemical etching requires applying a corrosion resistant layer to the non-processed area, and the processing is difficult to control due to poor isotropy, resulting in low etching efficiency and linearity. Summary of the Invention

[0006] In view of this, the present invention provides an ultrasonic vibration internal liquid electrochemical discharge-grinding processing device and a tool changing method, which are used to overcome the problems of low processing accuracy, poor surface quality, low processing efficiency, etc. in the process of processing hard and brittle materials, and realize high-quality, high-efficiency and low-cost processing of the processed materials.

[0007] In a first aspect, the present invention provides an ultrasonic vibration internal liquid electrochemical discharge-grinding processing device, characterized in that the device includes: an old tool holder, a new tool holder, an electric spindle, a spindle fixture, an auxiliary electrode, a workpiece to be processed, an electrolyte tank, a Hall current sensor, an automatic tool changer; an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool change operating system, and a position control system; wherein the tool holder includes a primary coil, a secondary coil, an ultrasonic transducer, a rotary liquid-passing joint, and a tool electrode;

[0008] The electric spindle is fixed on the machine tool by a spindle clamp, and the tool holder is fixed to the electric spindle by a rivet and a flat key. The tool holder is connected to the external fluid supply device through a rotary fluid joint. The external fluid supply device provides high-voltage electrolyte according to the fluid supply speed and transports the electrolyte to the front end of the tool electrode through the rotary fluid joint; the workpiece to be processed is horizontally fixed in the electrolyte tank by the workpiece clamp; the anode of the high-frequency pulse power supply is connected to the auxiliary electrode through a Hall current sensor, and the negative pole of the high-frequency pulse power supply is connected to the tool electrode; the ultrasonic generator is connected to the primary coil wire in the tool holder through a frequency converter and amplitude converter, the primary coil is contact-connected to the secondary coil, and the secondary coil is electrically connected to the ultrasonic transducer; the programmable frequency converter is used to control the speed of the electric spindle; the data acquisition device is used to automatically transmit and store the current signal of the Hall sensor; the high-frequency pulse power supply obtains the current detected by the Hall current sensor, the control end generates the feed amount according to the current feedback from the high-frequency pulse power supply, and the position control system controls the machine tool according to the feed amount to perform real-time positioning; the tool changing operating system controls the automatic tool changing device to change the tool holder according to the positioning of the position control system.

[0009] Optionally, the ultrasonic transducer includes piezoelectric ceramics and a variable amplitude rod; the ultrasonic generator sets the vibration frequency and vibration amplitude through the frequency converter, the ultrasonic generator emits a high-frequency electrical signal, which is transmitted to the ultrasonic transducer after electromagnetic induction between the primary coil and the secondary coil to charge the ultrasonic transducer, and the piezoelectric ceramics convert the electrical energy into mechanical vibration, and transmit the ultrasonic vibration energy to the tool electrode through the amplitude amplification effect of the variable amplitude rod.

[0010] Optionally, the machine tool is a 5-axis linkage machine tool, which includes a Z-axis motor, an X-axis motor, a Y-axis motor, a C-axis workbench and a B-axis tool.

[0011] Optionally, the tool electrode is an abrasive-plated tube electrode, and the front end of the tool electrode is plated with a diamond abrasive coating; the interior of the tool electrode is hollow, and the tool electrode adopts a double-hole structure.

[0012] Optionally, the vibration frequency of the ultrasonic generator is set to 25000Hz-30000Hz, and the vibration amplitude is 0um-10um; the external liquid supply device uses a micro-flow injection pump, the liquid supply speed range is 0mL / h-20mL / h, and the liquid supply pressure is 10MPa.

[0013] Optionally, the diamond abrasive grains are embedded in the surface of the tool electrode, and the protruding height G thereof is 2 / 3 of the overall height H of the diamond abrasive grains. The calculation formula for the protruding height G of the diamond abrasive grains is:

[0014] G=h+δ 气膜 +δ 电解液层 ,

[0015] Where h is the depth of the softening area of ​​the workpiece material, δ 气膜 is the film thickness, δ 电解液层 is the thickness of the electrolyte layer.

[0016] Optionally, the automatic tool changing device includes a disc-type tool magazine and a rotary tool holder; the disc-type tool magazine includes a motor, a tool, a clamping device and a tool magazine seat hole for releasing the tool; the rotary tool holder is provided with a rotary tool holder seat, including an old tool holder seat hole, a new tool holder seat hole, a linear motor and a center rotary motor; the center rotary motor is located at the rotation center, and the old tool holder seat hole and the new tool holder seat hole are respectively located at both ends of the center rotary motor.

[0017] In a second aspect, the present invention provides a tool changing method for ultrasonic vibration internal liquid electrochemical discharge-grinding processing, the method being implemented based on the first aspect or any one of the devices described in the first aspect, the method comprising the following steps:

[0018] Step S1: The position control system controls the machine tool to move to the positioning position according to the feed amount sent by the control end, wherein the machine tool movement includes the movement of the Z-axis motor, the X-axis motor, and the Y-axis motor, the rotation of the C-axis worktable, and the swing of the B-axis tool;

[0019] Step S2: The tool changing operating system controls the disc tool magazine and the rotary tool holder to move to the tool changing position through the motor according to the positioning position in step S1;

[0020] Step S3: After moving to the tool changing position in step S2, the disc-type tool magazine releases the new tool handle and places it into the new tool holder seat hole;

[0021] Step S4: After the new tool holder is placed in the new tool holder seat hole in step S3, the tool changing operating system is driven by the linear motor to move the old tool holder seat hole to the position of the old tool holder on the electric spindle. The electric spindle is driven by the Z-axis motor to move up and down to place the old tool holder in the old tool holder seat hole.

[0022] Step S5: After the old tool holder is placed in step S4, the central rotary motor drives the rotary tool holder to rotate, and the spatial positions of the old tool holder seat hole and the new tool holder seat hole are interchanged;

[0023] Step S6: After the spatial position exchange is completed in step S5, the electric spindle is driven by the Z-axis motor to move up and down, and the new tool holder is fixed in the electric spindle.

[0024] In a third aspect, the present invention provides a computer-readable storage medium, which includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the ultrasonic vibration internal liquid electrochemical discharge-grinding tool changing method in the second aspect.

[0025] In a fourth aspect, the present invention provides an electronic device comprising: one or more processors; a memory; and one or more computer programs, wherein the one or more computer programs are stored in the memory, and the one or more computer programs include instructions that, when executed by the device, cause the device to execute the ultrasonic vibration internal liquid electrochemical discharge-grinding tool changing method in the second aspect.

[0026] In the technical solution provided by the present invention, the processing device includes an old tool holder, a new tool holder, an electric spindle, a spindle clamp, an auxiliary electrode, a processing workpiece, an electrolyte tank, a Hall current sensor, an automatic tool changing device; an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool changing operating system, and a position control system; wherein the tool holder includes a primary coil, a secondary coil, an ultrasonic transducer, a rotary liquid joint, and a tool electrode. In the process of processing hard and brittle materials, the processing device integrates three technologies of ultrasonic vibration, mechanical grinding, and external rotation and internal liquid flow through the ultrasonic transducer, the tool electrode, and the external liquid supply device. By introducing ultrasonic vibration along the Z-axis, the thickness of the air film around the tool electrode is made more uniform, thereby improving the stability of electrochemical discharge machining; by precisely matching the size of the abrasive grains plated on the tool electrode with the depth of the discharge heat softening layer, the positive and precise coupling of the grinding action and the discharge heat action is achieved, thereby improving the processing quality; the electrolyte is continuously supplied to the tool electrode through the external liquid supply device, and the processing products in the discharge gap are promptly taken away, thereby improving the continuity of the processing. The present invention improves the continuity and stability of processing while ensuring processing efficiency, improves processing quality, and realizes high-quality, high-efficiency, and low-cost processing of processing materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 A simplified structural diagram of the overall processing device provided by an embodiment of the present invention;

[0029] Figure 2 A structural diagram of a knife handle provided by an embodiment of the present invention;

[0030] Figure 3 A diagram showing a double-hole structure of a tool electrode provided in an embodiment of the present invention;

[0031] Figure 4 A diagram showing the size matching of the abrasive layer of the tool electrode provided by an embodiment of the present invention;

[0032] Figure 5 A structural diagram of an ultrasonic transducer provided in an embodiment of the present invention;

[0033] Figure 6 A flowchart of a tool changing method for machining provided by an embodiment of the present invention;

[0034] Figure 7 A schematic diagram of an electronic device provided by an embodiment of the present invention.

[0035] In the figure: 1-old tool holder, 11-primary coil, 12-secondary coil, 13-ultrasonic transducer, 131-piezoelectric ceramic, 132-amplifier, 14-rotary liquid joint, 15-tool electrode, 151-diamond abrasive coating, 152-double-hole structure, 2-new tool holder, 31-disc tool magazine, 311-tool magazine seat hole, 32-rotary tool holder, 321-old tool holder seat hole, 322-new tool holder seat hole, 4-electric spindle, 41-spindle fixture, 5-auxiliary electrode, 6-processing workpiece, 7-electrolyte tank, 8-Hall current sensor, 9-Z-axis motor, 10-X-axis motor, 11-Y-axis motor, 12-C-axis worktable, 13-B-axis tool. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0037] It should be understood that the embodiments described are only a portion of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0038] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "an", "the" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0039] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0040] The word "if," as used herein, may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to the determination" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)," depending on the context.

[0041] Figure 1 A simplified structural diagram of the overall processing device provided by an embodiment of the present invention is shown in FIG. Figure 1 As shown, the device includes: an old tool holder 1, a new tool holder 2, an electric spindle 4, a spindle fixture 41, an auxiliary electrode 5, a workpiece 6, an electrolyte tank 7, a Hall current sensor 8, an automatic tool changer; an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool change operating system, and a position control system;

[0042] The electric spindle 4 is fixed on the machine tool by the spindle clamp 41, and the tool holder is fixed on the electric spindle 4 by rivets and flat keys. The tool holder is connected to the external liquid supply device through a rotary liquid joint 14. The external liquid supply device provides high-voltage electrolyte according to the liquid supply speed, and transports the electrolyte to the front end of the tool electrode 15 through the rotary liquid joint 14; the workpiece 6 is horizontally fixed in the electrolyte tank 7 by the workpiece clamp; the anode of the high-frequency pulse power supply is connected to the auxiliary electrode 5 through the Hall current sensor 8, and the negative pole of the high-frequency pulse power supply is connected to the tool electrode 15; the programmable frequency converter is used to control the speed of the electric spindle 4; the data acquisition device is used to automatically transmit and store the current signal of the Hall sensor 8; the high-frequency pulse power supply obtains the current detected by the Hall current sensor 8, and the control end generates the feed amount according to the current feedback from the high-frequency pulse power supply. The position control system controls the machine tool according to the feed amount to perform real-time positioning; the tool changing operating system controls the automatic tool changing device to change the tool holder according to the positioning of the position control system.

[0043] In the embodiment of the present invention, the control terminal includes but is not limited to a mobile phone, a tablet computer, a portable PC, a desktop computer, etc.

[0044] In the embodiment of the present invention, the machine tool is a 5-axis linkage machine tool, which includes a Z-axis motor 9 , an X-axis motor 10 , a Y-axis motor 11 , a C-axis worktable 12 and a B-axis tool 13 .

[0045] In the embodiment of the present invention, the material of the auxiliary electrode 5 is graphite; the material of the workpiece 6 is boron carbide; and the electrolyte is a sodium nitrate solution.

[0046] In this embodiment of the present invention, to ensure effective machining, the machining status must be monitored in real time. Hall effect current sensor 8 is used to receive the current signal during machining, observe the current waveform, compare the effects of various machining parameters on the machining process, and adjust parameters such as feed rate to achieve effective coordination between electrochemical discharge machining and mechanical grinding.

[0047] In the embodiment of the present invention, the voltage range of the high-frequency pulse power supply is 0V-120V, the frequency range is 10Hz-200000Hz, and the duty cycle range is 10%-90%. The rotation speed of the electric spindle 4 is 26000r / min.

[0048] In the embodiment of the present invention, the external liquid supply device is a micro-flow syringe pump, the liquid supply speed range is 0 mL / h-20 mL / h, and the liquid supply pressure is 10 MPa.

[0049] A micro-flow syringe pump was used as an external liquid supply device, while a syringe was used to temporarily store the electrolyte. The operating mode, output flow rate, and propulsion rate were set via the syringe pump control panel, further enhancing electrolyte supply. The experiment employed an external-to-internal liquid flow method. A rotary liquid flow connector 14 was designed and fabricated based on the machine tool. This connector allows for a fixed connection between the liquid inlet and the liquid supply pump, while the liquid outlet rotates synchronously with the electric spindle 4. Furthermore, a fixture was used to hold the tool electrode 15, enabling a rotating liquid spraying function.

[0050] In the embodiment of the present invention, Figure 1 As shown, the automatic tool changing device includes a disc-type tool magazine 31 and a rotary tool holder 32; the disc-type tool magazine 31 includes a motor, a tool, a clamping and a tool magazine seat hole 311 for releasing the tool; the rotary tool holder 32 is provided with a rotary tool holder seat, including an old tool holder seat hole 321, a new tool holder seat hole 322, a linear motor and a center rotary motor; the center rotary motor is located at the rotation center, and the old tool holder seat hole 321 and the new tool holder seat hole 322 are respectively located at both ends of the center rotary motor.

[0051] Figure 2 The structure diagram of the knife handle provided by the embodiment of the present invention is as follows: Figure 2 As shown, the tool handle includes a primary coil 11 , a secondary coil 12 , an ultrasonic transducer 13 , a rotary fluid-passing joint 14 , and a tool electrode 15 .

[0052] The ultrasonic generator is connected to the primary coil 11 in the tool handle through a frequency converter and an amplitude converter. The primary coil 11 is contact-connected to the secondary coil 12 , and the secondary coil 12 is electrically connected to the ultrasonic transducer 13 .

[0053] In the embodiment of the present invention, the rotary liquid-through joint 14 is located between the ultrasonic transducer 13 and the tool electrode 15 and is fixed by a threaded connection.

[0054] In the embodiment of the present invention, the tool electrode 15 is an abrasive-plated tube electrode made of brass, and a diamond abrasive coating 151 is plated on the front end of the tool electrode 15 .

[0055] Figure 3 The double hole structure diagram of the tool electrode provided in the embodiment of the present invention is as follows: Figure 3 As shown, the tool electrode 15 is hollow inside and adopts a double-hole structure 152 .

[0056] In this embodiment of the present invention, the tool electrode 15 employs a dual-hole structure 152, optimizing the external-to-internal flow technique. This increases the number of discharge locations and makes them more uniform. The dual-hole centers are different and continuously change during the rotation of the tool electrode 15, completely eliminating islanding and achieving complete material removal within the machining gap. This prevents clogging of the tool electrode 15, improves machining continuity, reduces secondary discharge at the sides due to clogging, reduces the taper of the machined hole, and improves machining quality.

[0057] Figure 4 The abrasive layer size matching diagram of the tool electrode provided in the embodiment of the present invention is as follows: Figure 4 As shown, the diamond abrasive grains are embedded in the surface of the tool electrode 15, and the protruding height G thereof is 2 / 3 of the overall height H of the diamond abrasive grains. The formula for calculating the protruding height G of the diamond abrasive grains is:

[0058] G=h+δ 气膜 +δ 电解液层 ,

[0059] Where h is the depth of the softening area of ​​the workpiece material, δ 气膜 is the film thickness, δ 电解液层 is the thickness of the electrolyte layer.

[0060] In the embodiment of the present invention, the particle size of the diamond abrasive grains used is 600#.

[0061] Figure 5 The structure diagram of the ultrasonic transducer provided in the embodiment of the present invention is as follows: Figure 5 As shown, the ultrasonic transducer 13 includes a piezoelectric ceramic 131 and a horn 132. The ultrasonic generator sets the vibration frequency and vibration amplitude through a frequency converter. The ultrasonic generator emits a high-frequency electrical signal, which is transmitted to the ultrasonic transducer 13 after electromagnetic induction between the primary coil 11 and the secondary coil 12, thereby charging the ultrasonic transducer 13. The piezoelectric ceramic 131 converts the electrical energy into mechanical vibration and transmits the ultrasonic vibration energy to the tool electrode 15 through the amplitude amplification effect of the horn 132.

[0062] In the embodiment of the present invention, the piezoelectric ceramics 131 are provided in four pieces, and a conductive sheet is provided between each piece of the piezoelectric ceramics 131 .

[0063] In the embodiment of the present invention, the vibration frequency of the ultrasonic generator is set to 25000 Hz-30000 Hz, and the vibration amplitude is 0 um-10 um.

[0064] In this embodiment of the present invention, ultrasonic vibration technology uses an ultrasonic generator and ultrasonic transducer to induce ultrasonic vibrations along the Z-axis, making the gas film thickness around the tool electrode 15 more uniform, thereby improving the stability of electrochemical discharge machining. During operation, the introduction of ultrasonic vibration technology utilizes ultrasonic cavitation to refine and even the hydrogen film, resulting in lower and more uniform single discharge energy, thereby improving machining quality and stability.

[0065] In this embodiment of the present invention, the tool electrode 15 is connected to the negative electrode of a high-frequency pulse power supply. Electrolysis occurs under the action of a DC voltage with the auxiliary electrode 5, which is connected to the positive electrode of the high-frequency pulse power supply. This generates hydrogen bubbles around the tool electrode 15. As these bubbles continuously form and aggregate, they form a bubble film surrounding the tool electrode surface. This insulates the tool electrode 15 from the electrolyte and creates a high potential difference between the tool electrode 15 surface and the electrolyte. When this potential difference is sufficient to penetrate the bubble film, a spark discharge occurs. The instantaneous high temperature and shock wave generated by the spark discharge melts and vaporizes the workpiece at the discharge point, ejecting it from the machining gap and achieving material removal. This is the electrochemical discharge machining process.

[0066] After electrochemical discharge machining, defects such as thermal cracks appear on the machined surface due to the energy removed by high-temperature etching. Mechanical grinding technology is introduced to achieve positive and precise coupling of grinding action and discharge thermal action by precisely matching the size of the abrasive grains plated on the tool electrode with the depth of the discharge thermal softening layer. The thermal softening layer formed by electrochemical discharge is precisely scraped off by diamond abrasive grains, thereby improving the machining quality of electrochemical discharge and achieving more precise control of the machining dimensions.

[0067] By introducing the external-to-internal fluid flow technology, an external fluid supply device continuously supplies high-voltage electrolyte to the machining gap via the tool electrode 15, which can promptly remove the discharge and grinding products in the discharge gap, prevent clogging of the machining gap, and promote the circulation of electrolyte in the electrolyte tank and the machining gap. On the other hand, due to the large aspect ratio of the machined small hole, as the machining depth increases, it is difficult for the electrolyte in the electrolyte tank 7 to flow into the machining gap, affecting the continuation of electrochemical discharge machining. By using the external-to-internal fluid flow technology, the electrolyte can directly reach the machining gap, which can ensure the continuation of discharge machining, improve the continuity of electrochemical discharge machining, and is suitable for the machining of small holes with a larger aspect ratio, thereby improving machining efficiency.

[0068] Figure 6 The flowchart of the tool changing method provided by the embodiment of the present invention is as follows: Figure 6 As shown, the method includes the following steps:

[0069] Step S1, the position control system controls the machine tool to move to the positioning position according to the feed amount sent by the control end, wherein the machine tool movement includes the movement of the Z-axis motor 9, the X-axis motor 10 and the Y-axis motor 11, the rotation of the C-axis worktable 12, and the swing of the B-axis tool 13.

[0070] In an embodiment of the present invention, at the beginning of processing, the outer diameter of the hole is likely to become larger due to side discharge, which in turn causes overcutting. Therefore, it is impossible to process a large hole on the workpiece at one time in the initial stage of processing; when the processing time reaches the preset time (for example, the preset time is 1 hour), the tool holder that clamps the tube electrode with a large outer diameter and a small hole diameter will be switched to process the workpiece. At this time, the control end will send the feed amount to the position control system, so that the position control system can control the machine tool to move to the positioning position according to the feed amount.

[0071] In an embodiment of the present invention, during the machining process, the high-frequency pulse power supply obtains the current detected by the Hall current sensor 8. When the detected current is less than a preset value (for example, the preset value is 1 mA), it indicates that the tool electrode 15 is severely worn and needs to be replaced with a tool holder for clamping a tube electrode of the same diameter. The control end generates a feed amount based on the current feedback from the high-frequency pulse power supply. At this time, the control end will send the feed amount to the position control system, and the position control system will control the machine tool to move to the positioning position based on the feed amount.

[0072] Step S2, tool change operation system controls the disc-type tool magazine 31 and the rotary tool holder 32 to move to the tool change position through the motor according to the positioning position in step S1.

[0073] Step S3 , after moving to the tool changing position in step S2 , the disc-type tool magazine 31 releases the new tool handle 2 and places it into the new tool holder seat hole 322 .

[0074] Step S4, after the new tool holder 2 is placed in the new tool holder seat hole 322 in step S3, the tool changing operating system is driven by the linear motor to move the old tool holder seat hole 321 to the position of the old tool holder 1 on the electric spindle 4, and the electric spindle 4 is driven up and down by the Z-axis motor 9 to place the old tool holder 1 into the old tool holder seat hole 321.

[0075] Step S5: After the old tool holder 1 is placed in step S4, the central rotary motor drives the rotary tool holder 32 to rotate, and the spatial positions of the old tool holder seat hole 321 and the new tool holder seat hole 322 are exchanged.

[0076] Step S6 , after the spatial position exchange is completed in step S5 , the electric spindle 4 is driven by the Z-axis motor 9 to move up and down, and the new tool holder 2 is fixed in the electric spindle 4 .

[0077] In the embodiment of the present invention, the tool changing method realizes an automated tool changing process, improves the processing capability, expands the processing range, and reduces errors caused by multiple installations.

[0078] In the technical solution of the operator compilation device provided by the present invention, the processing device includes an old tool holder, a new tool holder, an electric spindle, a spindle fixture, an auxiliary electrode, a processing workpiece, an electrolyte tank, a Hall current sensor, an automatic tool changing device; an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool changing operating system, and a position control system; wherein the tool holder includes a primary coil, a secondary coil, an ultrasonic transducer, a rotary liquid-passing joint, and a tool electrode. In the process of processing hard and brittle materials, the processing device uses ultrasonic The transducer, tool electrode, and external fluid supply device integrate three technologies: ultrasonic vibration, mechanical grinding, and external-to-internal fluid flow. By introducing ultrasonic vibration along the Z-axis, the thickness of the air film around the tool electrode becomes more uniform, improving the stability of electrochemical discharge machining. By precisely matching the size of the abrasive grains plated on the tool electrode with the depth of the discharge heat-softened layer, a positive and precise coupling of the grinding action and the discharge heat effect is achieved, improving machining quality. The external fluid supply device continuously supplies electrolyte to the tool electrode, promptly removing machining products from the discharge gap and improving machining continuity. While ensuring machining efficiency, this invention improves machining continuity and stability, enhances machining quality, and achieves high-quality, high-efficiency, and low-cost machining of the material being machined.

[0079] Figure 7 A schematic diagram of an electronic device provided by an embodiment of the present invention is shown in FIG. Figure 7 As shown, the electronic device 14 includes: a processor 141, a memory 142, and a computer program 143 stored in the memory 142 and executable on the processor 141. When the computer program 143 is executed by the processor 141, the ultrasonic vibration internal liquid electrochemical discharge-grinding tool changing method in the embodiment is implemented. To avoid repetition, they are not described here one by one.

[0080] The electronic device 14 includes, but is not limited to, a processor 141 and a memory 142. Those skilled in the art will understand that Figure 7 It is only an example of the electronic device 14 and does not constitute a limitation of the electronic device 14. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0081] The processor 141 may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0082] Memory 142 can be an internal storage unit of electronic device 14, such as a hard drive or memory of electronic device 14. Memory 142 can also be an external storage device of electronic device 14, such as a plug-in hard drive, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. equipped on electronic device 14. Furthermore, memory 142 can include both an internal storage unit of electronic device 14 and an external storage device. Memory 142 is used to store computer programs and other programs and data required by network devices. Memory 142 can also be used to temporarily store data that has been output or is about to be output.

[0083] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An ultrasonic vibration internal liquid electrochemical discharge-grinding processing device, characterized in that: The device comprises: an old tool holder (1), a new tool holder (2), an electric spindle (4), a spindle fixture (41), an auxiliary electrode (5), a workpiece (6), an electrolyte tank (7), a Hall current sensor (8), an automatic tool changer, an ultrasonic generator, a frequency converter, a high-frequency pulse power supply, a data acquisition device, an external liquid supply device, a programmable frequency converter, a tool change operating system, and a position control system; wherein the tool holder comprises a primary coil (11), a secondary coil (12), an ultrasonic transducer (13), a rotary liquid-through joint (14), and a tool electrode (15); The electric spindle (4) is fixed on the machine tool by a spindle fixture (41), the tool holder is fixed on the electric spindle (4) by a rivet and a flat key, the tool holder is connected to the external liquid supply device through a rotary liquid joint (14), the external liquid supply device provides high-voltage electrolyte according to the liquid supply speed, and transports the electrolyte to the front end of the tool electrode (15) through the rotary liquid joint (14); the workpiece (6) is fixed horizontally in the electrolyte tank (7) by the workpiece fixture; the anode of the high-frequency pulse power supply is connected to the auxiliary electrode (5) through the Hall current sensor (8), and the negative electrode of the high-frequency pulse power supply is connected to the tool electrode (15); the ultrasonic generator is connected to the tool electrode (15) through the frequency converter and the tool The primary coil (11) in the handle is connected by a wire, the primary coil (11) is contact-connected to the secondary coil (12), and the secondary coil (12) is electrically connected to the ultrasonic transducer (13); the programmable frequency converter is used to control the rotation speed of the electric spindle (4); the data collector is used to automatically transmit and store the current signal of the Hall current sensor (8); the high-frequency pulse power supply obtains the current detected by the Hall current sensor (8), the control end generates the feed amount according to the current feedback from the high-frequency pulse power supply, and the position control system controls the machine tool according to the feed amount to perform real-time positioning; the tool changing operating system controls the automatic tool changing device according to the positioning of the position control system to change the tool handle; The tool electrode (15) is an abrasive-coated tube electrode, and the front end of the tool electrode (15) is coated with a diamond abrasive coating (151); the interior of the tool electrode (15) is hollow, and the tool electrode (15) adopts a double-hole structure (152); The diamond abrasive grains are embedded in the surface of the tool electrode (15), and the protruding height G thereof is 2 / 3 of the overall height H of the diamond abrasive grains. The formula for calculating the protruding height G of the diamond abrasive grains is: G=h+d 气膜 +d 电解液层 , Where h is the depth of the softening area of ​​the workpiece material, δ 气膜 is the film thickness, δ 电解液层 is the thickness of the electrolyte layer.

2. The device according to claim 1, characterized in that The ultrasonic transducer (13) includes a piezoelectric ceramic (131) and a variable amplitude rod (132); the ultrasonic generator sets the vibration frequency and vibration amplitude through the frequency converter, and the ultrasonic generator emits a high-frequency electrical signal, which is transmitted to the ultrasonic transducer (13) after electromagnetic induction between the primary coil (11) and the secondary coil (12), thereby charging the ultrasonic transducer (13). The piezoelectric ceramic (131) converts the electrical energy into mechanical vibration, and transmits the ultrasonic vibration energy to the tool electrode (15) through the amplitude amplification effect of the variable amplitude rod (132).

3. The device according to claim 1, characterized in that The machine tool is a 5-axis linkage machine tool, which includes a Z-axis motor (9), an X-axis motor (10), a Y-axis motor, a C-axis workbench and a B-axis tool.

4. The device according to claim 2, characterized in that The vibration frequency of the ultrasonic generator is set to 25000Hz-30000Hz, and the vibration amplitude is 0 um-10um; the external liquid supply device uses a micro-flow injection pump, the liquid supply speed range is 0mL / h-20mL / h, and the liquid supply pressure is 10MPa.

5. The device according to claim 1, characterized in that The automatic tool changing device comprises a disc-type tool magazine (31) and a rotary tool holder (32); the disc-type tool magazine (31) comprises a motor, a tool, a clamping and a tool magazine seat hole (311) for releasing the tool; the rotary tool holder (32) is provided with a rotary tool holder seat, comprising an old tool holder seat hole (321), a new tool holder seat hole (322), a linear motor and a central rotary motor; the central rotary motor is located at the rotary center, and the old tool holder seat hole (321) and the new tool holder seat hole (322) are respectively located at two ends of the central rotary motor.

6. A tool changing method for ultrasonic vibration internal liquid electrochemical discharge-grinding processing, characterized in that: The method is implemented based on the device according to any one of claims 1 to 5, and the method comprises the following steps: Step S1, the position control system controls the machine tool to move to the positioning position according to the feed amount sent by the control end, wherein the machine tool moves the Z-axis motor (9), the X-axis motor (10) and the Y-axis motor, and the C-axis worktable rotates and the B-axis tool swings; Step S2, the tool changing operating system controls the disc-type tool magazine (31) and the rotary tool holder (32) to move to the tool changing position through the motor according to the positioning position in step S1; Step S3: After moving to the tool changing position in step S2, the disc-type tool magazine (31) releases the new tool handle (2) and places it into the new tool holder seat hole (322); Step S4: After the new tool holder (2) is placed into the new tool holder seat hole (322) in step S3, the tool changing operating system is driven by the linear motor to move the old tool holder seat hole (321) to the position of the old tool holder (1) on the electric spindle (4). The electric spindle (4) is driven by the Z-axis motor (9) to move up and down, and the old tool holder (1) is placed into the old tool holder seat hole (321); Step S5: After the old tool holder (1) is placed in step S4, the central rotary motor drives the rotary tool holder (32) to rotate, and the spatial positions of the old tool holder seat hole (321) and the new tool holder seat hole (322) are exchanged; Step S6: After the spatial position exchange is completed in step S5, the electric spindle (4) is driven by the Z-axis motor (9) to move up and down, and the new tool holder (2) is fixed in the electric spindle (4).

7. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the ultrasonic vibration internal liquid electrochemical discharge-grinding tool changing method according to claim 6.

8. An electronic device, characterized in that: include: one or more processors; Memory; and one or more computer programs, wherein the one or more computer programs are stored in the memory, and the one or more computer programs include instructions, which, when executed by the device, enable the device to perform the ultrasonic vibration internal liquid electrochemical discharge-grinding tool changing method described in claim 6.

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