High-energy electrical discharge milling machining gradient ring gas flushing and chip removal device and method

Abstract

The application discloses a high-energy electric spark milling machining gradient ring gas flushing chip removal device and method, and belongs to the technical field of electric spark machining. The device comprises a hollow electrode, the electrode is connected with the main shaft system of an electric spark machine tool through a clamp, and a ring flushing nozzle mechanism is arranged on the electrode. The ring flushing nozzle mechanism comprises a gas flushing nozzle, a circumferential driving assembly and an axial driving assembly. A ring-shaped air chamber is arranged in the gas flushing nozzle. A plurality of partition plates are uniformly arranged in the ring-shaped air chamber in the circumferential direction. The ring-shaped air chamber is divided into a plurality of air cavities by the partition plates. Each air cavity corresponds to an air inlet. An air outlet for spraying gas to the machining gap between the electrode and a workpiece is arranged at the bottom end of the air cavity. The spraying angles of the air outlets in the air cavities are different. While flushing liquid medium in the electric spark milling, the machining position is covered by multi-directional and flexible adjustable air flow. While realizing high-energy discharge and etching, the problem of accumulation of molten etching products in the machining gap is effectively solved, and efficient chip removal is realized.

Description

Technical Field

[0001] This invention belongs to the field of electrical discharge machining technology, specifically relating to a gradient ring punch gas chip removal device and method for high-energy electrical discharge milling. Background Technology

[0002] With the increasing demands for processing efficiency and precision in industry, high-energy pulse power supplies are being used more and more widely in electrical discharge machining (EDM). High-energy pulse power supplies can significantly improve material removal rates by increasing the energy of a single discharge, meeting the needs of large-scale, high-efficiency processing. However, in high-energy pulse machining, the volume of molten material generated in a single discharge increases significantly, making it much more difficult to remove the molten material. If the molten material cannot be removed from the machining gap in a timely and complete manner, it will not only cause frequent short circuits in the discharge channel, disrupting machining stability, but also cause the molten material to re-adhere to the workpiece surface or tool electrode, forming a large amount of recast material residue. Ultimately, this leads to decreased machining accuracy, deteriorated surface roughness, and even accelerated tool electrode wear, severely restricting the full realization of the advantages of high-energy pulse EDM technology.

[0003] In traditional electrical discharge machining (EDM), liquids (such as mineral oil and deionized water) are often used as the working medium. Their main functions are to compress the discharge channel, cool the machining area, insulate the discharge gap, and assist in chip removal. However, for high-energy pulse machining scenarios, liquid working media have significant limitations: Firstly, the rapid cooling rate of the liquid causes the molten material generated in the machining gap to cool and solidify quickly, forming solid debris. This solid debris has a much lower fluidity than the molten state and is difficult to remove by the flushing action of the liquid, easily clogging the machining gap. Secondly, some liquid working media (such as mineral oil) pose environmental pollution risks and are prone to producing fumes and carbon deposits at high temperatures, further affecting the machining environment and quality.

[0004] To address the aforementioned shortcomings of liquid working media, the use of gas as the working medium in electrical discharge machining (EDM) is being explored. Gas working media (such as compressed air and inert gases) offer advantages such as high fluidity and controllable cooling rates. This prevents molten material from solidifying due to rapid cooling and allows the airflow to directly remove it from the machining gap. Furthermore, gaseous working media are environmentally friendly and produce no oil fume pollution, making them theoretically more suitable for the chip removal requirements of high-energy pulse EDM.

[0005] However, due to the low density of the gas, when using only gas as the working medium, its compression effect on the discharge channel is weak, resulting in low discharge explosion energy, reduced material removal, and decreased processing efficiency. Its poor cooling performance also easily leads to overheating damage to the electrode and workpiece. Furthermore, existing gas working medium supply devices mostly adopt a single-direction, fixed-angle airflow structure, which suffers from poor adaptability between the airflow direction and the processing gap. They cannot adjust the jet angle of the airflow outlet or the distance between the airflow outlet and the processing gap according to the processing scenario (such as workpiece structure, processing depth, and electrode size), making it difficult to achieve multi-directional, flexible, and adjustable airflow coverage. This results in localized airflow "dead zones" within the processing gap, failing to effectively act on the molten material to be removed, ultimately failing to fully utilize the chip removal advantages of the gas working medium. Summary of the Invention

[0006] To address the problems of excessively rapid cooling in pure liquid media leading to chip removal difficulties, weak discharge channel compression in pure gas media, and the inability of the gas working medium supply device to adjust the jet angle of the airflow outlet and the distance between the airflow outlet and the machining gap, making it difficult to achieve multi-directional and flexible adjustable airflow coverage, this invention provides a gradient ring-jet gas chip removal device for high-energy electrical discharge milling.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A gradient ring-punch gas chip removal device for high-energy electrical discharge milling includes a hollow electrode for realizing high-energy electrical discharge milling. The hollow channel of the electrode is a liquid spraying channel. The electrode is connected to the spindle system of the electrical discharge milling machine tool through a fixture.

[0009] The electrode is equipped with a ring-jet nozzle mechanism;

[0010] The ring-shaped nozzle mechanism includes an air-purifying nozzle coaxially sleeved outside the electrode, a circumferential drive assembly for driving the air-purifying nozzle to rotate around the central axis of the electrode, and an axial drive assembly for driving the air-purifying nozzle to move along the electrode axis.

[0011] The air nozzle has an annular air chamber inside. Several baffles are evenly arranged in the annular air chamber along the circumference. The baffles divide the annular air chamber into several air cavities distributed along the circumference. Each air cavity corresponds to an air inlet on the outer wall of the air nozzle. The bottom of the air cavity is provided with an air outlet for spraying gas into the processing gap between the electrode and the workpiece.

[0012] The angle between the airflow direction along the outlet in each air chamber and the central axis of the annular air chamber is the jet angle of the outlet, and the jet angle of the outlet is different in each air chamber.

[0013] Preferably, the two sides of the air outlet along the radial direction of the annular air chamber are both conical surfaces and are arranged in parallel, with the small end of the conical surface facing the workpiece;

[0014] In all the air outlets, the central axis of each conical surface is collinear with the central axis of the annular air chamber;

[0015] The angle between the generatrix of the conical surface in the air outlet and the central axis of the annular air chamber is the injection angle.

[0016] Preferably, the spray angle of the air outlet is in the range of 30° to 60°.

[0017] Preferably, when looking up at the air nozzle, starting from the outlet with the smallest spray angle, the spray angle of each outlet increases sequentially in a clockwise or counterclockwise direction along the circumference of the annular air chamber.

[0018] Preferably, the outer arc of the bottom edge of the radially outer cone surface of all air outlets is on the same circle, and the radius of the inner arc of the bottom edge of the radially inner cone surface of all air outlets is not the same.

[0019] When looking up at the air nozzle, starting from the outlet with the smallest spray angle, the radius of the inner arc of each outlet decreases sequentially in a clockwise or counterclockwise direction along the circumference of the annular air chamber.

[0020] Preferably, the axial drive assembly includes a bracket mounted on the spindle system, a movable plate slidably fitted on the bracket along the axial direction of the electrode, a lead screw threaded onto the movable plate, both ends of the lead screw rotatingly fitted with the bracket, and one end of the lead screw being adapted and connected to an axial drive motor.

[0021] The upper part of the air nozzle rotates in conjunction with the moving plate.

[0022] Preferably, the movable plate is provided with a bearing, and the outer wall of the top end of the air nozzle is fixedly connected to the inner ring of the bearing.

[0023] Preferably, the support is provided with a slide rail extending along the axial direction of the electrode, and the movable plate is provided with a slide groove that slides in cooperation with the slide rail.

[0024] Preferably, the circumferential drive assembly includes a rotary motor mounted on the movable plate, wherein the output shaft of the rotary motor is coaxially and fixedly connected to the main pulley;

[0025] The top of the air nozzle is coaxially fixed with a pulley sleeved on the outside of the electrode;

[0026] The main pulley and the driven pulley are connected by a belt for transmission.

[0027] This invention also provides a method for high-energy electrical discharge milling with gradient ring punch gas chip removal.

[0028] A gradient ring-punch gas chip removal method for high-energy electrical discharge milling is implemented based on a gradient ring-punch gas chip removal device for high-energy electrical discharge milling. The chip removal method is as follows:

[0029] Step 1: Determine the number of milling layers based on the required milling depth and the thickness of each layer. Based on the distance between the end face to be milled and the upper end face of the workpiece during each layer of milling. Determine the range of airflow angles , These are the sequence numbers for each milling layer. The airflow angle is the angle between the airflow direction and the central axis of the annular air chamber.

[0030] Step 2, determine all spray angles are located at The internal air outlet serves as the first Air outlet assembly available for layer milling;

[0031] Step 3, determine the first The working air outlet for layer milling is as follows:

[0032] when When milling in the first layer, select one of the available air outlets in the group of available air outlets as the corresponding working air outlet;

[0033] when When milling, select one of the available air outlets from the available air outlet groups in each layer as the corresponding working air outlet, and the injection angle of the working air outlet during each layer of milling must meet the following conditions: ;

[0034] Step 4, determine the first During layer milling, the distance between the bottom end face of the air nozzle and the end face to be milled is... , making the first In layer milling, the outlet airflow can flush the machining gap between the electrode and the end face to be milled. , The radius of the radial outer edge of the bottom of the working air outlet;

[0035] Step 5: Perform layer-by-layer milling;

[0036] Conduct the first Before layer milling, move the air nozzle axially to a distance between the bottom end face and the end face to be milled. , will the The working air outlet of the layer milling is rotated to the front end of the electrode movement direction;

[0037] Electrode operation in the first stage During layer milling, liquid is continuously sprayed through the hollow through-holes of the electrodes. In layer milling, the working air outlet is always located at the front end of the electrode movement direction, and the machining gap is continuously flushed backward with air to remove chips.

[0038] The beneficial effects of this invention are:

[0039] (1) This invention sprays liquid through the hollow channel of the electrode and sprays air through the air nozzle. The liquid spray inside the electrode can compress the discharge channel and cool the electrode and the workpiece, while the air nozzle achieves efficient and environmentally friendly chip removal. Therefore, this invention sprays liquid medium inside the EDM milling process and covers the machining position with multi-directional and flexible airflow, achieving high-energy discharge erosion while effectively solving the problem of molten material accumulation in the machining gap, thus achieving efficient chip removal.

[0040] (2) In the present invention, the air nozzle has different spray angles at the air outlets in each air chamber, thereby adjusting the spray angle of the air outlet; the axial drive assembly in the present invention can adjust the distance between the air outlet and the workpiece, thereby adjusting the position of the machining gap between the electrode and the workpiece reached by the air jet from each air outlet; the circumferential drive assembly in the present invention can drive the air nozzle to rotate around the central axis of the electrode, thereby adjusting the orientation of each air outlet; the overall mechanism of the air nozzle, the axial drive assembly, and the circumferential drive assembly realizes multi-directional and flexible airflow coverage of the machining position during EDM, reduces the airflow "dead angle" in the local area of ​​the machining gap, effectively solves the problem of molten material accumulation in the machining gap, and achieves efficient chip removal. Attached Figure Description

[0041] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0042] Figure 1 This is a three-dimensional schematic diagram of the structure of the high-energy electrical discharge milling gradient ring punch gas chip removal device of the present invention;

[0043] Figure 2 This is a schematic diagram of the interaction between the air nozzle and the electrode in this invention;

[0044] Figure 3 This is a three-dimensional schematic diagram of the structure of the air nozzle in this invention;

[0045] Figure 4 This is a schematic bottom view of the structure of the air nozzle in this invention;

[0046] Figure 5 yes Figure 4Sectional view along axis AA;

[0047] Figure 6 This is a schematic diagram showing the distribution of each air outlet in this invention;

[0048] Figure 7 This is a schematic diagram of the operation of the present invention;

[0049] Figure 8 This is a diagram showing the change in the orientation of the working air outlet when the electrode moves in this invention.

[0050] in:

[0051] 1. Electrode; 2. Fixture; 3. Spindle system; 4. Air nozzle; 41. Central through hole; 42. Baffle; 43. Air chamber; 44. Air inlet; 45. Air outlet; 451. Conical surface; 452. Outer arc; 453. Inner arc; 46. First air outlet; 47. Second air outlet; 48. Third air outlet; 49. Fourth air outlet; 5. Workpiece; 6. Support; 61. Moving plate; 62. Lead screw; 63. Axial drive motor; 64. Bearing; 65. Slide rail; 7. Rotary motor; 71. Main pulley; 72. Driven pulley; 73. Belt. Detailed Implementation

[0052] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0053] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0054] In this invention, terms such as "upper," "lower," "bottom," and "top" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are merely relational terms determined for the convenience of describing the structural relationship of the various components or elements of this invention, and do not specifically refer to any component or element in this invention, and should not be construed as limiting this invention.

[0055] In this invention, terms such as "connected" and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0056] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0057] Example 1:

[0058] like Figures 1-5 As shown, a gradient ring-punch gas chip removal device for high-energy electrical discharge milling includes a hollow electrode 1 for realizing high-energy electrical discharge milling. The hollow channel of the electrode 1 is a liquid spraying channel. The electrode 1 is connected to the spindle system 3 of the electrical discharge milling machine tool through a fixture 2. The electrode 1, fixture 2, and spindle system 3 are all existing technologies.

[0059] The electrode 1 is equipped with a ring-jet nozzle mechanism;

[0060] The ring-shaped nozzle mechanism includes an air-purifying nozzle 4 coaxially sleeved outside the electrode 1, a circumferential drive assembly for driving the air-purifying nozzle 4 to rotate around the central axis of the electrode 1, and an axial drive assembly for driving the air-purifying nozzle 4 to move along the axial direction of the electrode 1; wherein the air-purifying nozzle 4 has a central through hole 41 for the electrode 1 to pass through in the middle.

[0061] The air nozzle 4 has an annular air chamber inside, and several partitions 42 are evenly arranged in the annular air chamber along the circumference. The partitions 42 divide the annular air chamber into several air cavities 43 distributed in the circumference. Each air cavity 43 corresponds to an air inlet 44 provided on the outer wall of the air nozzle 4. The bottom end of the air cavity 43 is provided with an air outlet 45 for spraying gas into the processing gap between the electrode 1 and the workpiece 5. The number of partitions 42 is 2 to 6.

[0062] The angle between the airflow direction along the outlet 45 in each air chamber 43 and the central axis of the annular air chamber is the jet angle of the outlet 45. The jet angle of the outlet 45 is different in each air chamber 43.

[0063] Preferably, the two sides of the air outlet 45 along the radial direction of the annular air chamber are both conical surfaces 451 and are arranged in parallel, with the small end of the conical surface 451 facing the workpiece 5.

[0064] In all the air outlets 45, the central axis of each conical surface 451 is collinear with the central axis of the annular air chamber;

[0065] The angle between the generatrix of the conical surface 451 in the air outlet 45 and the central axis of the annular air chamber is the injection angle.

[0066] Preferably, the spray angle of the air outlet 45 is in the range of 30° to 60°.

[0067] Preferably, when looking up at the air nozzle 4, starting from the air outlet 45 with the smallest spray angle, the spray angle of each air outlet 45 increases sequentially in a clockwise or counterclockwise direction along the circumference of the annular air chamber.

[0068] like Figure 6 As shown, it includes four air outlets 45, namely the first air outlet 46, the second air outlet 47, the third air outlet 48, and the fourth air outlet 49. The first air outlet 46 has the smallest spray angle. Starting from the first air outlet 46, the spray angles of the first air outlet 46, the second air outlet 47, the third air outlet 48, and the fourth air outlet 49 increase sequentially in a counterclockwise direction along the circumference of the annular air chamber.

[0069] Preferably, the outer arc 452 of the bottom edge of the radially outer cone 451 of all the air outlets 45 is located on the same circle, and the radius of the inner arc 453 of the bottom edge of the radially inner cone 451 of all the air outlets 45 is not the same, that is, the distance of the inner arc 453 of the bottom edge of the radially inner cone 451 of all the air outlets 45 from the central axis of the electrode 1 is not the same.

[0070] When looking up at the air nozzle 4, starting from the air outlet 45 with the smallest spray angle, the radius of the inner arc 453 in each air outlet 45 decreases sequentially in a clockwise or counterclockwise direction along the circumference of the annular air chamber.

[0071] like Figure 6 As shown, the first air outlet 46 has the smallest injection angle. Starting from the first air outlet 46, the radius of the inner arc 453 of the first air outlet 46, the second air outlet 47, the third air outlet 48, and the fourth air outlet 49 decreases sequentially in a counterclockwise direction along the circumference of the annular air chamber.

[0072] In this application, the air inlet 44 is connected to an external air supply system via an air pipe. The gas supply process is as follows: the external working gas medium (such as compressed air or nitrogen) is pressurized by the external air supply system and then delivered to the air inlet 44 of each air chamber 43 through the air pipe. After entering each independent air chamber 43, it is buffered and stabilized by the air chamber 43 and guided by the air outlet 45 to be sprayed at a corresponding spray angle into the machining gap between the electrode 1 and the workpiece 5. As the number of milling layers increases, the groove depth of the milled part also increases. As the groove depth increases, the spray angle of the selected air outlet 45 needs to be reduced.

[0073] Preferably, the axial drive assembly includes a bracket 6 mounted on the spindle system 3, a movable plate 61 slidably fitted on the bracket 6 along the axial direction of the electrode 1, a lead screw 62 threadedly fitted on the movable plate 61, the two ends of the lead screw 62 rotatingly fitted with the bracket 6, and one end of the lead screw 62 being adapted and connected to the axial drive motor 63.

[0074] The upper part of the air nozzle 4 is rotatably engaged with the movable plate 61.

[0075] Preferably, a bearing 64 is provided on the movable plate 61, and the outer wall of the top end of the air nozzle 4 is fixedly connected to the inner ring of the bearing 64, thereby realizing the rotational engagement between the air nozzle 4 and the movable plate 61.

[0076] Preferably, the support 6 is provided with a slide rail 65 extending along the axial direction of the electrode 1, and the moving plate 61 is provided with a slide groove that slides in cooperation with the slide rail 65.

[0077] In this application, the axial drive assembly can adjust the distance between the air outlet 45 and the workpiece 5, thereby adjusting the position of the machining gap between the electrode 1 and the workpiece 5 reached by the air jets from each air outlet 45.

[0078] Preferably, the circumferential drive assembly includes a rotary motor 7 mounted on the movable plate 61, and the output shaft of the rotary motor 7 is coaxially and fixedly connected to the main pulley 71.

[0079] The top of the air nozzle 4 is coaxially fixedly fitted with a pulley 72 that is sleeved on the outside of the electrode 1;

[0080] The main pulley 71 and the driven pulley 72 are connected by a belt 73.

[0081] In this application, the circumferential drive assembly can drive the air nozzle 4 to rotate around the central axis of the electrode 1, thereby adjusting the orientation of each air outlet 45.

[0082] Example 2:

[0083] A gradient ring-jet gas chip removal method for high-energy electrical discharge milling is implemented based on the gradient ring-jet gas chip removal device for high-energy electrical discharge milling in Example 1. The chip removal method is as follows:

[0084] Step 1: Determine the number of milling layers based on the required milling depth and the thickness of each layer. Based on the distance between the end face to be milled and the upper end face of the workpiece 5 during each layer of milling. Determine the range of airflow angles , These are the sequence numbers for each milling layer. The airflow impingement angle is the angle between the airflow direction and the central axis of the annular chamber; where the airflow impingement angle ranges... It can be customized according to the specific milling conditions;

[0085] Step 2, determine all spray angles are located at The internal air outlet 45 serves as the first Air outlet assembly available for layer milling;

[0086] Step 3, determine the first The working air outlet for layer milling is as follows:

[0087] when When milling in the first layer, select one of the available air outlets 45 as the corresponding working air outlet;

[0088] when During milling, one of the available air outlets 45° is selected from the available air outlet groups in each layer as the corresponding working air outlet, and the injection angle of the working air outlet during each layer of milling meets the following conditions: ;

[0089] Step 4, determine the first During layer milling, the distance between the bottom end face of the air nozzle 4 and the end face to be milled is... ,like Figure 7 As shown, make the first The airflow from the working outlet of the layer milling machine can flush the machining gap between electrode 1 and the end face to be milled. , The radius of the radial outer edge of the bottom of the working air outlet is the radius of the outer arc 452 of the working air outlet.

[0090] Step 5: Perform layer-by-layer milling;

[0091] Conduct the first Before layer milling, move the air nozzle 4 axially to a distance between the bottom end face and the end face to be milled. , will the The working air outlet of the layer milling is rotated to the front end of the moving direction of electrode 1;

[0092] Electrode 1 operates in the first stage During the layer milling process, liquid is continuously sprayed through the hollow through-hole of electrode 1. The working air outlet for layer milling is always located at the front end of electrode 1 in the direction of movement, continuously flushing the machining gap backward with air to remove chips. Figure 7 The arrow in the diagram indicates the direction of movement of electrode 1. Electrode 1 operates in the [number]th [phase]. During the layer milling process, the first The working air outlet for layer milling is always located at the front end of electrode 1 in the direction of movement, meaning that the first... The orientation of the working air outlet for layer milling is adjusted synchronously with the change in the moving direction of electrode 1, so that the first layer... The working air outlet for layer milling is always located at the front end of electrode 1 in the direction of movement, specifically as follows: Figure 8 As shown, Figure 8 The double-dotted line in the middle refers to the movement trajectory of electrode 1, and the arrow indicates the direction of movement of electrode 1.

[0093] The following example illustrates the specific chip removal method by setting four air outlets 45, with each outlet 45 having a spray angle of 60°, 50°, 40°, and 30°, respectively, and milling a rectangular groove with a depth of 3mm.

[0094] To mill a rectangular groove 3mm deep on workpiece 5, with each layer being 1mm thick, three layers need to be milled. During the first layer milling... The value is 0, and the airflow angle range is [55°, 60°]. During the second layer of milling, The airflow angle range is [40°, 50°], and the milling depth is 1mm. The airflow angle range is [30°, 45°], with a diameter of 2 mm.

[0095] During the first layer of milling, the air outlet assembly can include an air outlet 45 with a spray angle of 60°;

[0096] During the second layer of milling, the air outlet assembly can include an air outlet 45 with a spray angle of 40° and an air outlet 45 with a spray angle of 50°.

[0097] During the third layer of milling, the air outlet assembly can include an air outlet 45 with a spray angle of 30° and an air outlet 45 with a spray angle of 40°.

[0098] The final determination is as follows: the working air outlet for the first layer of milling is an air outlet 45 with a spray angle of 60°; the working air outlet for the second layer of milling is an air outlet 45 with a spray angle of 50°; and the working air outlet for the third layer of milling is an air outlet 45 with a spray angle of 40°. Of course, other air outlet combinations that meet the requirements can also be selected.

[0099] Then, based on the selected spray angle of the working air outlet, determine the distance between the bottom surface of the air nozzle 4 and the end face to be milled during milling.

[0100] Then, layer-by-layer milling is performed: Before milling the first layer, the air nozzle 4 is moved axially to a distance from the bottom end face to the end face to be milled. The working air outlet for the first layer of milling is rotated to the front end of the electrode 1 in the direction of movement. During the first layer of milling, liquid is continuously sprayed through the hollow through-hole of the electrode 1. The working air outlet for the first layer of milling is always located at the front end of the electrode 1 in the direction of movement, continuously flushing the machining gap backward to remove chips. Before the second layer of milling, the air nozzle 4 is moved axially to a distance from the end face to the end face to be milled. The working air outlet for the second layer of milling is rotated to the front end of the moving direction of electrode 1. During the second layer of milling, liquid is continuously sprayed through the hollow through-hole of electrode 1. The working air outlet for the second layer of milling is always located at the front end of the moving direction of electrode 1, continuously flushing the machining gap backward to remove chips. Before the third layer of milling, the air nozzle 4 is moved axially to a distance from the end face to the end face to be milled. The working air outlet of the third layer milling is rotated to the front end of the moving direction of electrode 1. During the operation of electrode 1 to perform the third layer milling, liquid is continuously sprayed through the hollow through hole of electrode 1. The working air outlet of the third layer milling is always located at the front end of the moving direction of electrode 1, and the machining gap is continuously flushed backward to remove chips.

[0101] In this invention, layer-by-layer milling and precise adjustment of the air outlet are achieved through the linkage control and position feedback closed loop of the CNC system on the EDM machine tool. The core control logic is as follows:

[0102] (1) Motor selection and control module: The axial drive motor 63 and the rotary motor 7 are both servo motors, equipped with pulse encoders to realize position feedback and establish communication with the CNC system on the EDM milling machine.

[0103] (2) Position control of layer-by-layer milling: The CNC system on the EDM milling machine tool is used to perform three-dimensional modeling of the workpiece to be machined. Then the CNC system performs layer-by-layer slicing and path planning to obtain the milling depth required for the workpiece to be machined, the thickness of each layer and the milling path; the CNC system on the EDM milling machine tool controls the relative position of electrode 1 and workpiece 5 to achieve layer-by-layer milling.

[0104] Based on the distance between the bottom surface of the air nozzle 4 and the end face to be milled calculated in the chip removal method, the CNC system sends a pulse command to the axial drive motor 63, which moves the air nozzle 4 to the target position through the lead screw drive; after it is moved into place, the pulse encoder on the axial drive motor 63 feeds back a signal to trigger the milling start command, realizing the linkage of "positioning in place - milling start".

[0105] (3) Precise adjustment of air outlet position: The drive motor 7 receives the angle positioning command from the CNC system and drives the air nozzle 4 to rotate through belt transmission, aligning the selected working air outlet with the front end of the electrode 1 in the moving direction.

[0106] The high-energy EDM milling gradient ring-punch gas chip removal device of the present invention can better remove chips, thereby improving the machining effect. Specifically, the axial drive motor 63 adjusts the up and down movement of the air nozzle 4 to ensure that the angle between the air nozzle 4 and the end of the electrode 1 is suitable for the thickness requirements of the current EDM milling layer; the rotation motor 7 ensures that the movement trajectory direction and the air punching direction are in a counter-current relationship, which can improve the chip removal effect and improve the stability of EDM.

[0107] Based on the moving trajectory of electrode 1, this invention calculates the rotation angle of the air nozzle 4 during the movement of electrode 1 using a numerical control system, thereby achieving synchronous adaptation between the working air outlet and the moving direction of electrode 1, as detailed below:

[0108] During electrical discharge milling, the CNC system on the electrical discharge milling machine reads the movement trajectory of electrode 1 (e.g., Figure 8 As shown by the double-dotted line, the trajectory is decomposed into several continuous small line segments. For example, the two ends of a certain line segment are points a and b, with corresponding coordinates (Xa, Ya) and (Xb, Yb) respectively. The CNC system calculates the angle β that the air nozzle 4 needs to rotate when the electrode moves from point a to point b according to the formula: β=arctan((Yb-Ya) / (Xb-Xa)), so as to ensure that the working air outlet is always opposite to the moving direction of the electrode 1.

[0109] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, they are not intended to limit the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A high-energy electrical discharge milling gradient ring punch gas chip removal device, characterized in that, It includes a hollow electrode (1) for realizing high-energy electrical discharge milling, the hollow channel of the electrode (1) is a liquid spraying channel, and the electrode (1) is connected to the spindle system (3) of the electrical discharge milling machine tool through a fixture (2); The electrode (1) is provided with a ring-jet nozzle mechanism; The ring-shaped nozzle mechanism includes an air nozzle (4) coaxially sleeved outside the electrode (1), a circumferential drive assembly for driving the air nozzle (4) to rotate around the central axis of the electrode (1), and an axial drive assembly for driving the air nozzle (4) to move along the axial direction of the electrode (1). The air nozzle (4) is provided with an annular air chamber inside. Several partitions (42) are evenly arranged in the annular air chamber along the circumferential direction. The partitions (42) divide the annular air chamber into several air cavities (43) distributed along the circumferential direction. Each air cavity (43) corresponds to an air inlet (44) provided on the outer wall of the air nozzle (4). The bottom end of the air cavity (43) is provided with an air outlet (45) for spraying gas into the processing gap between the electrode (1) and the workpiece (5). The angle between the airflow direction along the outlet (45) in each air chamber (43) and the central axis of the annular air chamber is the jet angle of the outlet (45). The jet angle of the outlet (45) in each air chamber (43) is different.

2. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 1, characterized in that, The two sides of the air outlet (45) along the radial direction of the annular air chamber are both conical surfaces (451) and are arranged in parallel, with the small end of the conical surface (451) facing the workpiece (5). In all the air outlets (45), the central axis of each conical surface (451) is collinear with the central axis of the annular air chamber; The angle between the generatrix of the conical surface (451) in the air outlet (45) and the central axis of the annular air chamber is the injection angle.

3. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 1, characterized in that, The spray angle of the air outlet (45) ranges from 30° to 60°.

4. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 1, characterized in that, When looking up at the air nozzle (4), starting from the outlet (45) with the smallest spray angle, the spray angle of each outlet (45) increases sequentially in a clockwise or counterclockwise direction along the circumference of the annular air chamber.

5. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 2, characterized in that, The outer arc (452) of the bottom edge of the radially outer cone (451) of all the air outlets (45) is on the same circle, and the radius of the inner arc (453) of the bottom edge of the radially inner cone (451) of all the air outlets (45) is inconsistent. When looking up at the air nozzle (4), starting from the air outlet (45) with the smallest spray angle, the radius of the inner arc (453) of each air outlet (45) decreases sequentially along the clockwise or counterclockwise direction of the circumference of the annular air chamber.

6. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 1, characterized in that, The axial drive assembly includes a bracket (6) mounted on the spindle system (3), a movable plate (61) slidingly fitted on the bracket (6) along the axial direction of the electrode (1), a lead screw (62) threaded onto the movable plate (61), the two ends of the lead screw (62) rotatingly fitted with the bracket (6), and one end of the lead screw (62) being adapted to and connected to the axial drive motor (63). The upper part of the air nozzle (4) rotates with the movable plate (61).

7. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 6, characterized in that, The movable plate (61) is provided with a bearing (64), and the outer wall of the top end of the air nozzle (4) is fixedly connected to the inner ring of the bearing (64).

8. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 6, characterized in that, The bracket (6) is provided with a slide rail (65) extending along the axial direction of the electrode (1), and the moving plate (61) is provided with a sliding groove that slides in cooperation with the slide rail (65).

9. The high-energy EDM milling gradient ring punch gas chip removal device as described in claim 6, characterized in that, The circumferential drive assembly includes a rotary motor (7) mounted on a movable plate (61), and the output shaft of the rotary motor (7) is coaxially and fixedly connected to the main pulley (71). The top of the air nozzle (4) is coaxially fixedly fitted with a pulley (72) that is sleeved on the outside of the electrode (1). The main pulley (71) and the driven pulley (72) are connected by a belt (73).

10. A gradient ring-punch gas chip removal method for high-energy electrical discharge milling, implemented based on the gradient ring-punch gas chip removal device for high-energy electrical discharge milling as described in any one of claims 1 to 9, characterized in that, The chip removal method is as follows: Step 1: Determine the number of milling layers based on the required milling depth and the thickness of each layer. According to the distance between the end face to be milled and the upper end face of the workpiece (5) during each layer of milling. Determine the range of airflow angles , These are the sequence numbers for each milling layer. The airflow angle is the angle between the airflow direction and the central axis of the annular air chamber. Step 2, determine all spray angles are located at The internal air outlet (45) serves as the first Air outlet assembly available for layer milling; Step 3, determine the first The working air outlet for layer milling is as follows: when When, select one of the available air outlets (45) in the first layer of milling as the corresponding working air outlet; when When milling, select one of the available air outlets (45) from the available air outlet groups in each layer as the corresponding working air outlet, and the injection angle of the working air outlet in each layer of milling shall meet the following conditions: ; Step 4, determine the first During layer milling, the distance between the bottom surface of the air nozzle (4) and the end face to be milled is... , making the first The outlet airflow of the working air port in layer milling can flush the machining gap between the electrode (1) and the end face to be milled, wherein , The radius of the radial outer edge of the bottom of the working air outlet; Step 5: Perform layer-by-layer milling; Conduct the first Before layer milling, the air nozzle (4) is moved axially to a distance from the bottom end face to the end face to be milled. , will the The working air outlet of the layer milling is rotated to the front end of the electrode (1) moving direction; Electrode (1) operates for the first time During the layer milling process, liquid is continuously sprayed through the hollow through-hole of electrode (1). The working air outlet of the layer milling is always located at the front end of the electrode (1) moving direction, and the machining gap is continuously flushed backward to remove chips.

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