A non-resonant ultrasonic vibration-assisted wire electric discharge cutting device

Abstract

The present invention belongs to the field of combined processing of metals and universal machine tools, and in particular relates to a non-resonant ultrasonic vibration-assisted electric spark wire cutting device, which solves the technical problems in the background technology. The electric spark wire cutting device includes an electric spark wire cutting component and an ultrasonic vibration auxiliary component. The electric spark wire cutting component includes a workbench, a wire electrode, and a wire guide wheel and a vibration guide wheel for guiding the wire electrode. The wire guide wheel is installed on the frame below the workbench, and the vibration guide wheel is connected to the frame above the workbench through a vibration bracket. The ultrasonic vibration auxiliary component includes an ultrasonic vibration system, which is fixedly connected to the vibration bracket through a fixed bracket, and the amplitude rod of the ultrasonic vibration system maintains contact with the vibration bracket. The ultrasonic vibration auxiliary system can provide a small amplitude, and utilizes the cavitation effect of ultrasonic machining to promote the circulation of the working fluid, thereby preventing the accumulation and clogging of the erosion products in the cutting seam; the micro-amplitude vibration is beneficial to the utilization of electric energy in electric spark machining and improves the electric spark discharge rate.

Description

Technical Field

[0001] The present invention relates to the technical field of combined metal processing and universal machine tools, and in particular to a non-resonant ultrasonic vibration-assisted electric spark wire cutting device. Background Art

[0002] During wire EDM, the wire electrode generates high temperatures by pulsed discharge into the metal workpiece, causing localized melting and vaporization in the workpiece's machining area. The melted and vaporized workpiece material is then etched into the working fluid. Etching products tend to accumulate and clog the kerf. When these accumulated products are not adequately cooled, the resulting discharge can easily cause large amounts of carbon-containing materials in the working fluid to adhere to the workpiece surface, leading to burns and reduced surface quality and machining efficiency.

[0003] Especially for EDM wire cutting of large thickness, in the middle position of the workpiece in the vertical direction, the working fluid sprayed by the upper and lower spray nozzles cannot be flushed to this position, resulting in the discharge products being unable to be discharged from the processing gap, the short circuit rate increases, and the efficiency of large thickness cutting is seriously reduced, which seriously hinders the application of EDM wire cutting technology in cutting large thickness workpieces. Summary of the Invention

[0004] In order to overcome the technical defects of existing electric spark wire cutting processing, in which the erosion products easily accumulate and clog in the cutting seam, causing burns to the workpiece, and reducing the surface quality of the workpiece and processing efficiency, the present invention provides an electric spark wire cutting device assisted by non-resonant ultrasonic vibration.

[0005] The present invention provides an electric spark wire cutting device assisted by non-resonant ultrasonic vibration, comprising an electric spark wire cutting component and an ultrasonic vibration auxiliary component. The electric spark wire cutting component comprises a workbench for fixing a workpiece to be processed, a wire electrode, and a wire guide wheel and a vibration guide wheel for guiding the wire electrode. The wire guide wheel is installed on a frame below the workbench, and the vibration guide wheel is connected to the frame above the workbench through a vibration bracket. One end of the vibration bracket is fixedly connected to the frame, and the other end is rotatably connected to the wheel axle of the vibration guide wheel. The wire electrode tensioning force is adjusted by adjusting the wire guide wheel and the vibration guide wheel; the ultrasonic vibration auxiliary component comprises an ultrasonic vibration system and a fixed frame. The ultrasonic vibration system is fixedly connected to the vibration bracket through the fixed frame, and the amplitude rod of the ultrasonic vibration system maintains contact with the vibration bracket.

[0006] The ultrasonic vibration system is connected to the vibration transmission bracket via a fixed bracket. The output frequency and power of the ultrasonic vibration system are continuously adjustable. The corresponding ultrasonic frequency is selected based on the pulse discharge frequency during wire EDM, and the appropriate output power is selected based on the vibration transmission bracket. The ultrasonic vibration system converts high-frequency electrical energy into mechanical energy. The ultrasonic vibration system maintains contact with the vibration transmission bracket, and the vibration transmission guide wheel is rotatably connected to the vibration transmission bracket. When the vibration transmission bracket vibrates, the vibration transmission guide wheel also drives the wire electrode to vibrate simultaneously. The ultrasonic vibration system indirectly drives the wire electrode to ultrasonic motion, assisting the wire EDM process. Therefore, during wire EDM, the ultrasonic vibration auxiliary system can provide a small amplitude that matches the pulse discharge frequency during wire EDM. The cavitation effect of ultrasonic machining promotes the circulation of the working fluid, preventing the accumulation of erosion products in the kerf. At the same time, the micro-amplitude vibration of ultrasonic machining facilitates the utilization of electrical energy during EDM, improving the EDM discharge rate. Incorporating ultrasonic machining into wire EDM can effectively improve machining efficiency.

[0007] Preferably, the vibration direction of the ultrasonic vibration system is perpendicular to the direction of the wire electrode. This arrangement is conducive to the discharge of the erosion products from the kerf, further avoiding the accumulation of erosion products that may cause burns to the workpiece, and improving the surface quality and processing efficiency of the workpiece.

[0008] Preferably, the vibration transmission bracket is a right-angled bend plate, the horizontal portion of the right-angled bend plate is used for fixed connection to the frame, the vertical portion of the right-angled bend plate is used for rotationally connecting to the vibration transmission guide wheel, the ultrasonic vibration system is connected to the horizontal portion of the right-angled bend plate through a fixed frame, the ultrasonic vibration system is arranged horizontally as a whole, the amplitude rod of the ultrasonic vibration system is kept in contact with the vertical portion of the right-angled bend plate, and one or more vibration-damping notches are provided on the inner corners of the right-angled bend plate. The vibration-damping notch is intended to reduce the rigidity in the vibration direction, and the right-angled bend plate is a flat plate in a right-angle shape. The vibration transmission bracket includes but is not limited to the above structure, and the position and size of the vibration-damping notch can be set according to the specific structure of the vibration transmission bracket. The provision of the vibration-damping notch is beneficial to improving the transmission efficiency of the ultrasonic vibration and reducing unnecessary energy loss. The ultrasonic vibration system can select a suitable output power according to the shape, size and position of the vibration-damping notch on the vibration transmission bracket.

[0009] Preferably, a hemispherical contact block is fixedly connected to the end of the ultrasonic vibration system's horn, and a circular contact piece that mates with the hemispherical contact block is fixedly connected to the vibration transmission bracket. Both the hemispherical contact block and the circular contact piece are made of a material with a hardness greater than HRA80. The ultrasonic vibration system transmits vibrations to the vibration transmission bracket via the hemispherical contact block and the circular contact piece, thereby improving the stability of the entire system during ultrasonic vibration transmission.

[0010] Preferably, the hemispherical contact block and the circular contact piece maintain a contact state with a certain preload force.

[0011] Preferably, the vibration transmission bracket is made of spring steel or beryllium bronze, specifically 65Mn spring steel or 60Si2Mn alloy spring steel.

[0012] Preferably, the vibration frequency of the ultrasonic vibration system is 15KHz~50KHz.

[0013] Compared with the prior art, the technical solution provided by the present invention has the following advantages: it can improve the processing efficiency and surface quality of electric spark wire cutting; the present invention adopts a vibration transmission bracket with a notch, which is beneficial to improving the transmission efficiency of ultrasonic vibration and reducing unnecessary energy loss; the present invention adopts a hemispherical contact block and a circular contact piece as the medium for ultrasonic vibration transmission, which improves the robustness of the entire system during ultrasonic vibration transmission; when performing electric spark wire cutting operations, the ultrasonic vibration auxiliary system can provide a small amplitude that meets the pulse discharge frequency during electric spark wire cutting, and utilizes the cavitation effect of ultrasonic processing to promote the circulation of the working fluid, thereby avoiding the accumulation and blockage of erosion products in the cutting seam, and thus avoiding burns of the workpiece; at the same time, the micro-vibration of ultrasonic processing is beneficial to the utilization of electric energy in electric spark processing, improves the electric spark discharge rate, further ensures the surface quality of the processed workpiece and improves the processing efficiency, especially can improve the processing efficiency of cutting large thickness workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] Figure 1 This is a schematic structural diagram of a non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to the present invention.

[0017] In the figure: 1. Wire guide wheel; 2. Workbench; 3. Workpiece to be processed; 4. Wire electrode; 5. Vibration guide wheel; 6. Vibration bracket; 7. Circular contact piece; 8. Hemispherical contact block; 9. Ultrasonic vibration system; 10. Fixed bracket. DETAILED DESCRIPTION

[0018] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0019] In the description, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance. It should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, removable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms based on specific circumstances.

[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all the embodiments.

[0021] The following is combined with Figure 1 Specific embodiments of the present invention are described in detail.

[0022] In one embodiment, Figure 1 As shown, a non-resonant ultrasonic vibration-assisted electric spark wire cutting device includes an electric spark wire cutting component and an ultrasonic vibration auxiliary component. The electric spark wire cutting component includes a workbench 2 for fixing a workpiece 3 to be processed, a wire electrode 4, and a wire guide wheel 1 and a vibration guide wheel 5 for guiding the wire electrode 4. The wire guide wheel 1 is installed on the frame below the workbench 2, and the vibration guide wheel 5 is connected to the frame above the workbench 2 through a vibration bracket 6. One end of the vibration bracket 6 is fixedly connected to the frame, and the other end is rotatably connected to the axle of the vibration guide wheel 5. The tension of the wire electrode 4 is adjusted by adjusting the wire guide wheel 1 and the vibration guide wheel 5; the ultrasonic vibration auxiliary component includes an ultrasonic vibration system 9 and a fixed frame 10. The ultrasonic vibration system 9 is fixedly connected to the vibration bracket 6 through the fixed frame 10, and the amplitude rod of the ultrasonic vibration system 9 maintains contact with the vibration bracket 6.

[0023] The ultrasonic vibration system 9 is connected to the vibration transmission support 6 via a fixed bracket 10. The output frequency and output power of the ultrasonic vibration system 9 are continuously adjustable. The corresponding ultrasonic frequency is selected based on the pulse discharge frequency during wire EDM, and the appropriate output power can be selected based on the vibration transmission support 6. The ultrasonic vibration system 9 converts high-frequency electrical energy into mechanical energy. Furthermore, the ultrasonic vibration system 9 maintains contact with the vibration transmission support 6, and the vibration transmission guide wheel 5 is rotatably connected to the vibration transmission support 6. When the vibration transmission support 6 vibrates, the vibration transmission guide wheel 5 also drives the wire electrode 4 to vibrate simultaneously. The ultrasonic vibration system 9 then indirectly drives the wire electrode 4 to ultrasonic motion, assisting the wire EDM process. Therefore, during wire EDM, the ultrasonic vibration auxiliary system can provide a small amplitude that matches the pulse discharge frequency during wire EDM. The cavitation effect of ultrasonic machining promotes the circulation of the working fluid, preventing the accumulation of erosion products in the kerf. Furthermore, the micro-amplitude vibration of ultrasonic machining facilitates the utilization of electrical energy during EDM, increasing the EDM discharge rate. Incorporating ultrasonic machining into wire EDM can effectively improve machining efficiency.

[0024] Based on the above embodiment, in a preferred embodiment, the vibration direction of the ultrasonic vibration system 9 is perpendicular to the direction of the wire electrode 4. This configuration facilitates the discharge of erosion products from the kerf, further preventing the accumulation of erosion products that could cause burns on the workpiece, and improving the surface quality and machining efficiency of the workpiece.

[0025] Based on the above embodiment, in a preferred embodiment, the vibration transmission bracket 6 is a right-angled bent plate. The horizontal portion of the plate is fixedly connected to the frame, and the vertical portion of the plate is rotatably connected to the vibration transmission guide wheel 5. The ultrasonic vibration system 9 is connected to the horizontal portion of the plate via a fixing bracket 10. The ultrasonic vibration system 9 is arranged horizontally. The horn of the ultrasonic vibration system 9 maintains contact with the vertical portion of the plate. One or more vibration-damping notches are provided at the inner corners of the plate. The plate is a flat plate with a right angle. The vibration-damping notches are intended to reduce rigidity in the vibration direction. The vibration transmission bracket 6 includes but is not limited to the above-mentioned structure, and the position and size of the vibration-damping notches can be adjusted according to the specific structure of the vibration transmission bracket 6. The wire electrode 4 is parallel to the vertical portion of the plate, and the horn of the ultrasonic vibration system 9 is perpendicular to the vertical portion of the plate. The provision of the vibration-damping notches helps improve the transmission efficiency of ultrasonic vibrations and reduce unnecessary energy loss. The ultrasonic vibration system 9 can select an appropriate output power based on the shape, size, and position of the vibration-damping notches on the vibration transmission bracket 6.

[0026] Based on the above embodiment, in a preferred embodiment, a hemispherical contact block is fixedly connected to the end of the horn of the ultrasonic vibration system 9, and a circular contact piece 7 that matches the hemispherical contact block is fixedly connected to the vibration transmission bracket 6. Both the hemispherical contact block and the circular contact piece 7 are made of a material with a hardness greater than HRA80. The ultrasonic vibration system 9 transmits vibrations to the vibration transmission bracket 6 via the hemispherical contact block 8 and the circular contact piece 7, thereby improving the stability of the entire system during ultrasonic vibration transmission.

[0027] Based on the above embodiment, in a preferred embodiment, the hemispherical contact block and the circular contact piece 7 maintain contact with each other with a certain preload force. In a specific embodiment, the preload force can be 10N to 1000N, depending on the material of the bracket and the size of the gap.

[0028] Based on the above embodiment, in a preferred embodiment, the vibration transmission bracket 6 is made of spring steel or beryllium bronze, specifically 65Mn spring steel or 60Si2Mn alloy spring steel.

[0029] Based on the above embodiment, in a preferred embodiment, the vibration frequency of the ultrasonic vibration system 9 is 15KHz to 50KHz.

[0030] The above description is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Although detailed descriptions have been made with reference to the aforementioned embodiments, those skilled in the art should understand that they may still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents; and such modifications or replacements do not deviate from the essence of the corresponding technical solutions within the scope of the technical solutions of the embodiments, and they should all be included in the scope of protection of the claims.

Claims

1. A non-resonant ultrasonic vibration-assisted wire electric discharge cutting device, characterized in that: The invention comprises an electric spark wire cutting component and an ultrasonic vibration auxiliary component, wherein the electric spark wire cutting component comprises a workbench (2) for fixing a workpiece (3) to be processed, a wire electrode (4), and a wire guide wheel (1) and a vibration guide wheel (5) for guiding the wire electrode (4), wherein the wire guide wheel (1) is mounted on a frame below the workbench (2), and the vibration guide wheel (5) is connected to the frame above the workbench (2) through a vibration bracket (6), wherein one end of the vibration bracket (6) is fixedly connected to the frame, and the other end is rotatably connected to the wheel shaft of the vibration guide wheel (5), and the tension of the wire electrode (4) is adjusted by adjusting the wire guide wheel (1) and the vibration guide wheel (5); the ultrasonic vibration auxiliary component comprises an ultrasonic vibration system (9) and a fixed frame (10), wherein the ultrasonic vibration system (9) is fixedly connected to the vibration bracket (6) through the fixed frame (10), and the amplitude rod of the ultrasonic vibration system (9) is kept in contact with the vibration bracket (6); The vibration transmission bracket (6) is a right-angle bent plate, the horizontal portion of the right-angle bent plate is used for fixed connection to the frame, the vertical portion of the right-angle bent plate is used for rotationally connecting to the vibration transmission guide wheel (5), the ultrasonic vibration system (9) is connected to the horizontal portion of the right-angle bent plate through the fixing frame (10), the ultrasonic vibration system (9) is arranged horizontally as a whole, the amplitude rod of the ultrasonic vibration system (9) is kept in contact with the vertical portion of the right-angle bent plate, and one or more vibration-damping notches are provided on the inner corner of the right-angle bent plate.

2. The non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to claim 1, characterized in that: The vibration direction of the ultrasonic vibration system (9) is perpendicular to the direction of the wire electrode (4).

3. A non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to claim 1 or 2, characterized in that: A hemispherical contact block is fixedly connected to the end of the amplitude rod of the ultrasonic vibration system (9), and a circular contact piece (7) adapted to the hemispherical contact block is fixedly connected to the vibration transmission bracket (6). Both the hemispherical contact block and the circular contact piece (7) are made of a material with a hardness greater than HRA80.

4. The non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to claim 3, characterized in that: The hemispherical contact block and the circular contact piece (7) maintain a contact state with a certain preload force.

5. The non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to claim 4, characterized in that: The vibration transmission bracket (6) is made of spring steel or beryllium bronze.

6. The non-resonant ultrasonic vibration-assisted wire electric discharge cutting device according to claim 5, characterized in that: The vibration frequency of the ultrasonic vibration system (9) is 15KHz~50KHz.

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