Novel electrode device for electric spark machining

Abstract

The invention relates to a novel electric spark machining electrode device which comprises tungsten steel electrode bars, at least one tungsten steel electrode bar is connected with an electrode block, the electrode block is connected with an adapter, and at least one layer of red copper wire is wound around the end of each tungsten steel electrode bar and matched with a mounting hole of the electrode block to achieve connection. According to the technical scheme, the electrode loss can be reduced, the electrode applicability is enhanced, the machining stability and the machining precision are improved, and the high-quality and high-efficiency electrode machining device is provided for the field of electric spark finish machining.

Description

Technical Field

[0001] The present invention relates to the field of small-hole electrical discharge machining, and particularly to an electrode device for a new type of electrical discharge machining. Background Art

[0002] Electrical discharge machining is a special machining method that melts and vaporizes local metal by the instantaneous high temperature generated during discharge. It has unique advantages such as non-contact machining, being unrestricted by the strength and hardness of materials, and high machining accuracy. Therefore, it is increasingly widely used in the high-efficiency precision machining and micro-machining of machining materials in industrial fields such as aerospace, transportation, and mold manufacturing. The discharge electrode is the main executing device of electrical discharge machining, equivalent to the tool of a cutting machine tool. Therefore, the quality of the machining electrode directly affects the accuracy and effect of electrical discharge machining. In the prior art, due to improper selection of electrode materials or improper fixing methods during the electrical discharge machining process, there are obvious electrode loss problems, which directly affect the efficiency and accuracy of electrical discharge machining. At the same time, in high-precision machining fields such as aerospace, due to the special-shaped structure of the machined parts or special processing requirements, the machining path is narrow and the machining angle is complex. The electrode is usually a slender rod with poor stiffness, large deformation, and easy to deviate. And in the process of small-hole machining, it is difficult to observe the machining part and the electrode movement at some positions, resulting in easy machining deviation, which may seriously cause the workpiece to be scrapped, and the electrode is easy to break, ultimately affecting the finished product effect and benefit of electrical discharge machining. Therefore, improving electrode loss, enhancing electrode applicability, and improving machining stability and machining accuracy are problems that need to be solved urgently. Summary of the Invention

[0003] The invention object of the present invention is to disclose a new type of electrode device for electrical discharge machining with small electrode loss, high machining stability, and fast and accurate positioning, and the length of the machining electrode can be adjusted according to the machining needs.

[0004] The technical solution to realize the present invention is as follows:

[0005] A new type of electrode device for electrical discharge machining includes a tungsten carbide electrode rod 1. At least one tungsten carbide electrode rod 1 is connected to an electrode block 2, the electrode block 2 is connected to a transfer seat 3, and at least one layer of copper wire is wound around the end of the tungsten carbide electrode rod 1 and is connected by fitting with the mounting hole of the electrode block 2.

[0006] The transfer seat 3 is connected to a quick-change reference piece 5.

[0007] A connecting block 4 is provided between the electrode block 2 and the transfer seat 3.

[0008] The electrode block 2 and the connecting block 4 are fixedly connected by a screw structure, or the electrode block 2 and the connecting block 4 are movably connected by a pin shaft and then fixedly connected through a fixing member.

[0009] The upper section of the electrode block 2 is rod-shaped, and the lower section is flat-shaped.

[0010] One end of the connecting block 4 is placed in the slot of the adapter base 3 and tightened by a lateral screw 6 to achieve fine adjustment of the connecting block 4 in the vertical direction.

[0011] The axial direction of the tungsten steel electrode rod 1 is parallel to the length direction of the connecting block 4, or the included angle between the above two directions is an acute angle less than 30°.

[0012] The electrode block 2 is of an L-shaped structure, and the upper surface of its flat lower section is an inclined surface, or the electrode block 2 is a multi-folded Z-shaped, and the upper surface of its flat section is a curved surface, and the lower surface is an inclined surface.

[0013] A novel electrode device for electric discharge machining provided by the technical solution of the present invention uses the mounting holes on the electrode block 2 to connect and fix the electrode rod 1. Through the clearance fit between the two and soldering with copper wire, the accurate positioning and fixation of the electrode rod 1 are realized. Moreover, tungsten steel alloy is used as the material of the electrode rod 1, which has a high melting point and good electrical conductivity. Under high-temperature conditions, the deformation and loss of the electrode are extremely small, and it is not easy to deform during the processing, reducing the number of electrode replacements. Combining with the clearance fit structure, the high-precision repeated replacement of the electrode rod 1 can be realized; the electrode block 2 and the adapter base 3 are set to be detachably connected, and different-shaped electrode blocks 2 can be replaced according to different processing requirements, increasing the applicable environment and processing ability of the electrode. It is particularly obvious for the processing of multi-connected guide vane film holes with complex structures. Without multiple electrode devices, only by replacing the electrode block 2, the processing requirements of the blade film holes with multiple angles and structures can be realized; a connecting block 4 is arranged at the lower end of the electrode block 2 to extend the length of the electrode block 2, so that the electrode block 2 and the electrode rod 1 can extend into more concealed and deeper areas, increasing the processing area and use space of the electrode; a quick-change reference piece 5 is installed at the lowermost end of the electrode device to establish a unified standard with the machine tool reference surface, realizing the quick positioning and assembly of the electrode device and the machine tool, and improving the processing accuracy and processing efficiency. Therefore, the novel electrode device for electric discharge machining provided by the technical solution of the present invention can improve electrode loss, enhance electrode applicability, and improve processing stability and processing accuracy, providing a high-quality and high-efficiency electrode processing device for the field of electric discharge finishing machining. Description of the Drawings

[0014] Figure 1 It is a schematic diagram of the overall structure of a novel electrode device for electric discharge machining;

[0015] Figure 2 It is a side view schematic diagram of the structure of a novel electrode device for electric discharge machining;

[0016] Figure 3 It is a schematic diagram of the overall structure of an embodiment of a novel electrode device for electric discharge machining;

[0017] Figure 4 Schematic diagram of an electrode block structure of an electrode device for a new type of electrical discharge machining;

[0018] Figure 5 Schematic diagram of another electrode block structure of an electrode device for a new type of electrical discharge machining;

[0019] Figure 6 Schematic diagram of the overall structure of an electrode device for a new type of electrical discharge machining from an inverted perspective;

[0020] Figure 7 Schematic diagram of a partial enlarged structure of the electrode rod and electrode block area of an electrode device for a new type of electrical discharge machining;

[0021] Figure 8 Schematic diagram of the connection of a quick-change reference piece of an electrode device for a new type of electrical discharge machining to the machine tool for quick fixation; Figure 9 Schematic diagram of the application of an electrode device for a new type of electrical discharge machining. Specific embodiments

[0022] The following details the specific implementation manners of the present invention. It should be noted that the description of the specific implementation manners of the present invention is for facilitating a comprehensive understanding of the technical content of the present invention and should not be regarded as a limitation on the protection scope of the claims of the present invention.

[0023] The terms "including" or "comprising" and the like used in this disclosure are intended to mean that the elements before this word are covered by the requirements listed after this word, and do not exclude the possibility of also covering other elements.

[0024] For the components not described in detail in this part, the specific model parameters of the components, and the mutual relationships between the components, they can be considered as technologies, methods, and devices known to those of ordinary skill in the relevant technical fields. However, in appropriate cases, the said technologies, methods, and devices should be regarded as part of the specification.

[0025] The technical solution of the specific embodiment of the present invention is:

[0026] An electrode device for a new type of electrical discharge machining, including a tungsten carbide electrode rod 1. At least one tungsten carbide electrode rod 1 is connected to an electrode block 2, and the electrode block 2 is connected to an adapter base 3. At least one layer of copper wire is wound around the end of the tungsten carbide electrode rod 1, and it is connected by cooperating with the mounting hole of the electrode block 2.

[0027] As Figure 1As shown in the figure, the electrode device for the new type of electric discharge machining includes at least one tungsten steel electrode rod 1, an electrode block 2 and an adapter base 3. The tungsten steel electrode rod 1 is arranged at one end of the electrode block 2. An installation hole with a diameter size equivalent to that of the electrode rod 1 is opened at this end of the electrode block 2. The end of the electrode rod 1 is inserted into the installation hole to be connected with the electrode block 2. The number of installation holes matches the number of electrode rods 1 or is more than the number of electrode rods 1. The electrode rod 1 passes through the installation hole and extends about 1 - 2 mm out of the electrode block 2. A whole piece of highly conductive copper wire 14 is wound around the electrode rod 1 for at least one layer, and then soldered to fix the copper wire 14 to the electrode rod 1. Preferably, when the electrode rod 1 extends 1.5 mm out of the electrode block 2 and two layers of copper wire 14 are wound. The copper wire 14 has good ductility and conductivity, does not occupy too much space when wound around the electrode rod 1 and is convenient for winding. Winding two layers can not only fix the electrode rod 1 and the electrode block 2 but also enhance the conductivity of the electrode, and can avoid the problems of insecure winding with one layer, occupying space and wasting materials with multiple layers of winding. The electrode rod 1 is made of tungsten steel material. The tungsten steel material has a high melting point, and the electrode rigidity is better than that of other commonly used discharge materials (such as tungsten copper, graphite). During the electric discharge machining process, the loss is small, which can increase the service life of the electrode rod 1, reduce the frequency of replacing the electrode rod 1 during the machining process, and the diameter of the installation hole is the same as that of the electrode rod 1, and the two form a clearance fit. The installation holes on the electrode block 2 are electrode wire small holes made by high-precision five-axis engraving and milling machines for high-speed drilling. The aperture tolerance and position tolerance are both within 0.005 mm, and the tolerance is within 0.01 mm after the tungsten steel electrode rod 1 is repeatedly replaced. Therefore, when the electrode rod 1 is inserted into the installation hole, the position can be fixed, and high-precision repeated positioning of the electrode rod 1 can be achieved. The adapter base 3 is arranged at the lower end of the electrode block 2. A groove is opened on the upper surface of the adapter base 3. The lower end of the electrode block 2 is inserted into the groove, and the lateral bolt is tightened to press the lower end of the electrode block 2 against the inner side surface of the groove, realizing the connection and fixation between the electrode block 2 and the adapter base 3.

[0028] The said adapter base 3 is connected with a quick-change reference plate 5.

[0029] The electrode device for the new type of electric discharge machining further includes a quick-change reference plate 5. The quick-change reference plate 5 is arranged at the lower part of the adapter base 3 and is threadedly connected with the adapter base 3 through at least three screws. The adapter base 3 is provided with holes corresponding to the screws at the bottom, and the quick-change reference plate 5 is provided with holes penetrating up and down corresponding to the screws. After the upper surface of the quick-change reference plate 5 is attached to the lower surface of the adapter base 3 and the hole positions are aligned, the screws are screwed into the adapter base 3 from the bottom of the quick-change reference plate 5 and tightened to fix the quick-change reference plate 5 at the bottom of the adapter base 3. At the same time, by adjusting the screws, the levelness of the electrode device for the new type of electric discharge machining is adjusted; such as Figure 8As shown, four grooves are provided at the bottom of the quick-change reference piece 5 in four directions, and the four grooves are arranged in a cross distribution. The quick-change reference piece 5 is connected to a pneumatic chuck 11 on the machine tool workbench through a floating bayonet device 10. The four grooves at the bottom are respectively engaged and connected with the carbide positioning posts 12 of the pneumatic chuck 11. The Z-direction reference plane 13 on the top surface and the X-direction and Y-direction reference planes on the side surfaces of the four positioning posts 12 of the pneumatic chuck 11 are respectively attached to the respective surfaces in the grooves on the quick-change reference piece 5, so that the quick-change reference piece 5 is matched and positioned with the reference plane of the machine tool, playing the role of connecting and fixing the electrode device to the machine tool. Through this quick-change reference piece 5, the electrode device can be quickly connected and fixed to the machine tool, facilitating the positioning and replacement of the electrode device. Particularly, four internal hexagonal screws are provided at the four corners of the quick-change reference piece 5, and four square grooves 15 are provided at the bottom of the quick-change reference piece 5.

[0030] A connecting block 4 is provided between the electrode block 2 and the adapter block 3.

[0031] As Figure 4 As shown, a connecting block 4 is provided at the lower end of the electrode block 2, and the lower end of the connecting block 4 is connected to the adapter block 3; a connecting block 4 is provided between the electrode block 2 and the adapter block 3. On the one hand, it is used to connect the electrode block 2 and the adapter block 3, and on the other hand, it is used to extend the length of the electrode block 2, so that the electrode block 2 and the electrode rod 1 can extend into areas with complex paths to approach the position to be machined.

[0032] The electrode block 2 and the connecting block 4 are fixedly connected by a screw structure, or the electrode block 2 and the connecting block 4 are movably connected by a pin shaft and then fixedly connected through a fixing member. The electrode block 2 and the connecting block 4 can be rotatably connected, and there are precise scale lines at appropriate positions on the electrode block 2 or the connecting block 4.

[0033] As Figure 4As shown, the electrode block 2 and the connecting block 4 are detachably connected. Specifically, the bottom surface of the electrode block 2 is fitted with the top surface of the connecting block 4. Three through holes are provided at the bottom corresponding to the bottom surface of the electrode block 2. The three through holes have different apertures and are arranged in a line along the projection direction of the arrangement direction of the mounting holes of the electrode block 2. Among the three through holes, the through holes at both ends are pin holes, which are connected with the cylindrical pins 7 and 8. The through hole in the middle is a threaded hole, which is connected with the screw 9. The threaded hole in the middle is connected with the screw 9. By fine-tuning the position of the screw 9 and controlling the tightening force, the positional relationship between the connecting block 4 and the electrode block 2 can be fine-tuned in the horizontal direction, and the electrode block 2 and the connecting block 4 can be fixed. The two cylindrical pins 7 and 8 are of different sizes and are used to determine the installation direction of the electrode block 2 and the connecting block 4. To prevent reverse installation and confirm the fixed position of the electrode block 2 and the connecting block 4, and to prevent relative displacement between the electrode block 2 and the connecting block 4, preferably, the screw 9 is a hexagon socket screw, and the cylindrical pins 7 and 8 are Ø4*16 cylindrical pins and Ø5*16 cylindrical pins, respectively. Alternatively, the electrode block 2 and the connecting block 4 are connected by a pin, which allows the electrode block 2 to rotate about the pin. When the electrode block 2 rotates to a desired angle, the electrode block 2 and the connecting block 4 are fixed together by screws or fastening structures. This rotation can appropriately adjust the angle between the electrode block 2 and the connecting block 4, and in essence, also adjusts the macrostructure of the electrode block 2, allowing the electrode rod 1 to enter the specific part of the part for processing. The precise marking can improve the accuracy and efficiency of the adjustment. This structure is not specifically shown in the figure.

[0034] The upper section of the electrode block 2 is rod-shaped, and the lower section is flat.

[0035] The upper section of the electrode block 2 is set to a rod shape, and the lower section is set to a flat shape, forming a Z-shaped or L-shaped special-shaped structure as a whole. The electrode block 2 is used in different shapes according to the distribution of the processing position and the interference situation, so as to facilitate electrode processing; in particular, the workpiece to be processed is a multi-jointed guide blade of an aircraft engine. Since the multi-jointed guide blade has two blade bodies in front and behind, the area where the small hole to be processed between the two blade bodies is hidden and there is interference. This area is defined as a shielding area. The path to enter the shielding area is narrow, and the processing angle is complex. The upper section of the electrode block 2 is set to It is in the shape of a vertical rod, with a flat lower section and a Z-shaped overall structure. The electrode rod 1 is horizontally inserted into the rod-shaped end of the electrode block 2, so that the electrode block 2 and the electrode rod 1 extend into the shielded area along the narrow space between the two blades and approach the position of the small hole to be processed. The horizontally inserted electrode rod 1 is used to process the small holes arranged in the X-axis direction. When processing the small holes arranged in the Z-axis direction, the upper section of the electrode block 2 is set to be in the shape of a horizontal rod, and the lower section is flat. The overall structure is in the shape of an L-type. The electrode rod 1 is longitudinally inserted into the rod-shaped end of the electrode block 2, and the electrode block 2 and the electrode rod 1 are extended into the shielded area for processing.

[0036] One end of the described connecting block 4 is placed in the groove of the adapter block 3, and is pressed by the lateral screw 6 to achieve fine adjustment in the vertical direction of the connecting block 4.

[0037] A groove is provided on the upper surface of the adapter block 3. The lower end of the connecting block 4 is inserted into the groove. At least one through hole is provided on one side surface of the adapter block 3. The lateral screw 6 is horizontally inserted into the through hole from the side surface of the adapter block 3 and presses the connecting block 4 located in the groove to fix the connecting block 4 and the adapter block 3; the lower end of the connecting block 4 is inserted into the groove. The longitudinal depth of the lower end of the connecting block 4 can be finely adjusted according to different machining positions and different machining directions of the machined small holes. Specifically, after the lower end of the connecting block 4 enters the groove, it does not contact the bottom surface of the groove. By tightening the lateral screw 6, the two sides of the lower end of the connecting block 4 are clamped with the other inner side surface of the groove to fix the connecting block 4, or the lower end of the connecting block 4 contacts and abuts against the inner bottom surface of the groove, and then the lateral screw 6 is tightened to fix the connecting block 4 and the adapter block 3; particularly, the workpiece to be machined is a double-guide vane. The lower end of the connecting block 4 is inserted into the groove of the adapter block 3 and abuts against the inner bottom surface of the adapter block 3, and then the connecting block 4 is pressed by the lateral screw 6 to stably fix the connecting block 4 and the adapter block 3. Preferably, two lateral screws 6 are provided to press the connecting block 4.

[0038] The axial direction of the described tungsten carbide electrode rod 1 is parallel to the length direction of the connecting block 4, or the included angle between the above two directions is an acute angle less than 30°.

[0039] The axial direction of the electrode rod 1 is set to be parallel to the length direction of the connecting block 4. In the case where the machining path is narrow and the movement space of the electrode is limited, the electrode device can adapt to the narrow machining path, enabling the electrode rod 1 and the connecting block 4 to enter the long and narrow machining area in the same direction for electrode machining, reducing the requirement for the accommodation space of the machining area due to the multi-angle setting of each component on the device. The included angle between the electrode rod 1 and the connecting block 4 can also be set to be less than 30°. Within this angle range, the connection and fixation structure between the electrode rod 1 and the connecting block 4 is stable. After the electrode rod 1 extends into the limited machining area, by using the certain angle between the electrode rod 1 and the connecting block 4, the electrode rod 1 can be rotated to machine the part to be machined within a certain range in the machining area, so as to reduce the frequency of the electrode rod 1 entering and exiting multiple times due to the angle of the electrode rod 1, thereby improving the overall machining efficiency.

[0040] The described electrode block 2 is of an L-shaped structure, the upper surface of its lower flat part is an inclined surface, or the electrode block 2 is of a multi-folded Z-shaped structure, the upper surface of its flat part is a curved surface, and the lower surface is an inclined surface.

[0041] When processing the small holes on the multi-stage guide vanes of an aero-engine, since the multi-stage guide vanes have at least two blade bodies, the space between the blade bodies is narrow and the path is curved, which causes interference in the processing of the small holes on the blade bodies. According to the occlusion of the processing path during the small hole processing, when processing the small holes arranged in the Z direction on the blade body, the electrode block 2 is set to an L-shaped structure. Its upper section is set as a horizontal rod shape, and the upper surface of the flat lower section is set as an inclined surface, which is matched with the cross-sectional shape of the blade concave of the blade body close to the blade body to be processed, facilitating the electrode block 2 to extend into the space between the two blade bodies. And the rod-shaped part of the upper section of the electrode block 2 can continue to extend horizontally to reach the processing position of the small hole to be processed. The electrode rod 1 is longitudinally inserted into the rod-shaped end of the upper section of the electrode block 2, and moving the electrode rod 1 along the Z axis direction completes the processing of the small holes arranged in the Z direction on the blade body. When processing the small holes arranged in the X direction on the blade body, the electrode block 2 is set to a Z-shaped or multi-folded Z-shaped structure. The upper section of the electrode block 2 is set as a longitudinal rod shape, and the upper surface of the flat part of the electrode block 2 is set as a curved surface, which protrudes towards the blade concave of the blade to be processed and is matched with the shape of the blade concave to prevent the electrode block 2 from colliding with the blade concave during movement and processing, affecting the processing. The lower surface of the flat part of the electrode block 2 is set as an inclined surface, so that when the electrode block 2 extends into the processing area between the two blade bodies, the electrode block 2 will not touch the leading edge of the blade body to be processed, enabling the electrode block 2 and the electrode rod 1 to approach the position of the small hole to be processed to the greatest extent, effectively avoiding contact and collision with the blade, and realizing an accurate and stable precision processing process.

[0042] Although the present invention has been described in conjunction with specific embodiments, it is obvious that many substitutions, modifications, and variations will be apparent to those skilled in the art. Therefore, the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and its concept of the present invention, to make changes, substitutions, and combinations should be covered within the protection scope of the present invention.

Claims

1. A novel electrode device for electric discharge machining, comprising a tungsten steel electrode rod (1), characterized in that, At least one tungsten carbide electrode rod (1) is connected to the electrode block (2), and the electrode block (2) is connected to the adapter base (3). At least one layer of copper wire is wound around the end of the tungsten carbide electrode rod (1), and it is connected by fitting into the mounting hole of the electrode block (2).

2. The electrode device for the novel electric discharge machining according to claim 1, characterized in that, The adapter base (3) is connected to the quick-change reference piece (5).

3. The electrode device for new type electric spark machining according to claim 1 or 2, characterized in that, A connecting block (4) is provided between the electrode block (2) and the adapter base (3).

4. The electrode device for new electric discharge machining according to claim 3, characterized in that, The electrode block (2) and the connecting block (4) are fixedly connected by a screw structure, or the electrode block (2) and the connecting block (4) are movably connected by a pin shaft, and then fixedly connected through a fixing member.

5. The electrode device for the novel electric discharge machining according to claim 4, characterized in that, The electrode block (2) and the connecting block (4) are rotatably connected, and there are precise scale lines at appropriate positions on the electrode block (2) or the connecting block (4).

6. The electrode device for the novel electric spark machining according to claim 5, characterized in that, The upper section of the electrode block (2) is rod-shaped, and the lower section is flat.

7. The electrode device for the novel electric spark machining according to claim 6, characterized in that, One end of the connecting block (4) is placed in the groove of the adapter base (3) and pressed by a lateral screw (6) to achieve fine adjustment of the connecting block (4) in the vertical direction.

8. The electrode device for new type electric spark machining according to claim 7, characterized in that, The axial direction of the tungsten carbide electrode rod (1) is parallel to the length direction of the connecting block (4), or the included angle between the above two directions is an acute angle less than 30°.

9. The electrode device for the new type of electric discharge machining according to claim 8, characterized in that, The electrode block (2) is of an L-shaped structure, and the upper surface of its flat lower section is an inclined surface, or the electrode block (2) is of a multi-folded Z-shaped structure, and the upper surface of its flat part is a curved surface and the lower surface is an inclined surface.

Images