Electrode capable of machining two square holes simultaneously and using and manufacturing method thereof

Abstract

The invention discloses an electrode capable of machining two square holes at the same time and a using and manufacturing method of the electrode, and relates to the technical field of electric spark punching. The electrode comprises an electrode clamping part, the two ends of the short edge of one side of the electrode clamping part are connected with electrode working parts with square sections, and each electrode working part comprises a working section a, a working section b, a working section c and a working section d which are sequentially connected in the direction from the free end to the connecting end of the electrode working part. When the electrode is used, rough machining, semi-finish machining, finish machining and ultra-finish machining can be synchronously carried out on the two square holes through the working sections on the two electrode working parts. According to the electrode capable of machining the two square holes at the same time and the using and manufacturing method of the electrode, simultaneous machining of the two square holes of a high-precision valve part can be completed, and electrode loss is reduced while the requirement that the inner angle of the square holes is not larger than R0.05 mm is met.

Description

Technical Field

[0001] The invention relates to the technical field of electric spark drilling, in particular to an electrode capable of processing two square holes simultaneously and a use and manufacturing method thereof. Background Art

[0002] like Figure 1 、 2 The valve body shown in the figure comprises a horizontally arranged cylindrical valve body 1. An axial passage 11 is defined within the cylindrical valve body 1, extending axially throughout the entire body. The upper surface of the cylindrical valve body 1 also includes two countersunk holes 12 arranged sequentially along the direction of the axial passage 11. Each countersunk hole 12 has a square hole 13 at its bottom axial center, which communicates with the axial passage 11.

[0003] When using existing EDM equipment to machine high-precision valve body parts with two small square holes, factors such as insufficient electrode strength and large repeated positioning errors caused by electrode replacement make it difficult for the EDMed valve body parts to meet design requirements for dimensional accuracy and form and position tolerance. For example, the inner corner radius of some square holes is required to be no larger than R0.05mm, and the sharp corners of the electrode are also the most vulnerable and weakest points of the electrode. As a result, the inner corner radius of the machined valve body parts is generally greater than R0.1mm, which in turn results in a low pass rate for EDM of such valve body parts. Furthermore, if the electrode is replaced multiple times to achieve an inner corner radius no larger than R0.05mm and manual labor is used to ensure that the inner corner of the square hole is no larger than R0.05mm, production costs will be significantly increased.

[0004] At the same time, if the single-hole processing method is used for double-hole valve body parts, the production efficiency will be low and cannot meet the needs of production tasks; and the electrode loss will be serious - on average, more than 1-2 electrodes will be consumed for each hole processed, so each double-hole valve body part will require more than 2-3 electrodes.

[0005] In addition, these high-precision electrodes are currently produced as single pieces, resulting in high production costs. Summary of the Invention

[0006] The first object of the present invention is to provide an electrode that can simultaneously process two square holes, which can complete the simultaneous processing of two square holes of high-precision valve body parts and reduce electrode loss while meeting the requirement that the inner angle of the square hole is no more than R0.05mm.

[0007] The second object of the present invention is to provide a method for using the above-mentioned electrode.

[0008] The third object of the present invention is to provide a method for mass-producing the above-mentioned electrodes.

[0009] The technical solution to the first technical problem of the present invention is: an electrode capable of simultaneously processing two square holes, comprising an electrode clamping portion with a rectangular sheet-like structure, both ends of a short side of one side of the electrode clamping portion are connected to an electrode working portion extending in the same direction as its long side and having a square cross-sectional shape, the electrode working portion comprising a working segment a, a working segment b, a working segment c and a working segment d which are sequentially connected from its free end to the connection end.

[0010] As a further improvement of the present invention, a concave groove is provided on the short side of the electrode clamping portion between the two electrode working portions.

[0011] As a further improvement of the present invention, the electrode working portion and the electrode clamping portion have the same thickness and are an integrated structure.

[0012] As a further improvement of the present invention, the axial lengths of the working segments a, b, c, and d are not less than the depth of the square hole.

[0013] The technical solution of the present invention to solve the second technical problem is: a method for using an electrode capable of simultaneously processing two square holes, comprising the following steps: S1. Install the electrode on the EDM equipment and find the positive electrode; S2. Align the cylindrical valve body to be processed on the workbench and set the countersunk hole on the cylindrical valve body vertically upward; S3. Use the electric spark machining equipment to move the electrodes horizontally to the top of the cylindrical valve body, and make the free ends of the two electrode working parts face the two countersunk holes respectively; S4. Square hole roughing: Driven by the EDM equipment, the free end faces of the two electrode working parts are gradually fed downward from the upper end face of the countersink until the lower ends of the two working sections a penetrate the bottom surfaces of the two countersinks and connect the axial channels. During this process, only the working section a in the electrode working part performs discharge work, and after completing the square hole roughing, the electrode is raised and reset; S5. Square hole semi-finishing: Driven by the EDM equipment, the free end faces of the two electrode working parts are gradually fed downward from the upper end face of the countersink until the lower ends of the two working sections b respectively penetrate the bottom surfaces of the two countersinks and reach the axial channel. During this process, only the working section b in the electrode working part performs discharge work, and after completing the square hole semi-finishing, the electrode is raised and reset; S6. Through the reverse polarity EDM process, the working sections a and b of the electrode working part are self-destroyed, so that the lower end of the working section c becomes the new free end of the electrode working part, leaving enough downward feed space for subsequent processing; S7, Square Hole Finishing: Driven by the EDM equipment, the free end faces of the two electrode working parts are gradually fed downward from the upper end face of the countersink until the lower ends of the two working sections C respectively penetrate the bottom surfaces of the two countersinks and reach the axial channel. During this process, only the working section C in the electrode working part performs discharge work, and after completing the square hole finishing, the electrode is raised and reset; S8, Square Hole Superfinishing: Driven by the EDM equipment, the free end faces of the two electrode working sections are gradually fed downward from the upper end face of the countersunk hole until the lower ends of the two working sections d respectively penetrate the bottom surfaces of the two countersunk holes and reach the axial channel. During this process, only the working section d of the electrode working section performs discharge work. After completing the square hole superfinishing, the electrodes are raised and reset, completing the simultaneous machining of the two square holes of the first cylindrical valve body. S9. After the processing is completed, only the finished cylindrical valve body is removed without removing the electrode. Then, the next cylindrical valve body is clamped and aligned according to the previous steps S2 and S3. The working section c of the old electrode is continued to be used for rough machining of the square hole of the new cylindrical valve body, and the working section d of the old electrode is used for semi-finishing of the square hole of the new cylindrical valve body. After the semi-finishing of the square hole is completed, a new electrode is replaced and the electrode is aligned according to the steps of S1. The working section a of the new electrode is used for finishing, and the working section b of the new electrode is used for super-finishing. This reciprocating cycle can realize the continuous production of cylindrical valve bodies.

[0014] As a further improvement of the present invention, step S1 is specifically as follows: After vertically clamping the electrode on the Z axis of the EDM equipment through the electrode clamping part, use a micrometer to find the positive electrode working part so that the total runout of each vertical surface of the electrode is 0.001mm.

[0015] As a further improvement of the present invention, step S2 specifically includes the following steps: S2.1. Use a dial indicator to align the horizontal surface of the workbench so that the horizontal surface runout of the workbench is 0.001mm; S2.2. Insert the aligning core shaft into the axial passage of the cylindrical valve body and press the cylindrical valve body onto the workbench by fixing the end of the aligning core shaft so that the countersunk hole on the cylindrical valve body is vertically facing upward. S2.3. Use a micrometer to align the busbars on both ends of the mandrel to ensure that the total runout is 0.001mm. Then, use an electrode to electrically induct the mandrel to complete the front and back centering. Use an electrode to electrically induct the two end surfaces of the cylindrical valve body to complete the left and right centering. This completes the alignment of the cylindrical valve body. S2.4. Remove the aligning core shaft and prepare to process the cylindrical valve body.

[0016] As a further improvement of the present invention, step S6 is specifically as follows: A flat plate made of the same material as the electrode working part is fixed horizontally on the workbench. The parallelism of the thickness of the flat plate is 0.01mm. When the electrode needs to be self-destroyed, the polarity of the EDM equipment is changed, the pulse width and discharge gap are adjusted, and then the electrode working part is used to perform EDM on the flat plate to remove the used working parts of the electrode working part.

[0017] The technical solution of the present invention to solve the third technical problem is: a method for manufacturing an electrode capable of simultaneously processing two square holes, comprising the following steps: S1. Prepare a rectangular block fixture, insert and fix six blanks in two parallel rows on the rectangular block fixture, and tighten the blanks with screws so that a section of the blank is overhanging at one end as the processed section; S2. Connect the rectangular block fixture to the 3R fixture on the wire cutting processing equipment; S4. Programming a cutting path using a wire cutting machine so that the wire cutting path sequentially passes through the processing segments on a row of blanks, thereby cutting the processing segments of the six blanks into the shape of electrodes at one time. The "rough 2 and fine 3" method is used for cutting, and five cutting passes are performed to obtain a semi-finished electrode with a grinding allowance. S5. Rotate the special fixture 90° clockwise or counterclockwise, cut the blank along the thickness direction, and slice the blank into two electrodes along the thickness direction. When cutting, use the same "rough 2 and fine 3" method, perform 5 cuts, and retain grinding allowance; S6, cutting the processing section of the blank to obtain 12 semi-finished electrodes; S7, extract the remaining blanks by translation, feed the blanks, and repeat the steps of S4 and S5 until the blanks are fully utilized, thereby obtaining a batch of semi-finished electrodes; S8. Select a grinding tool with a slotted surface. The depth of the slotted surface is 0.1mm smaller than the thickness of the semi-finished electrode, and the flatness of the bottom surface of the slotted surface is 0.001mm. S9. Place the semi-finished electrode flat in the slot of the grinding tool, grind the two thickness surfaces of the electrode, then take out the semi-finished electrode and grind the edge side of the electrode to ensure that the shape and position tolerance and dimensional accuracy of the electrode meet the design requirements. At the same time, keep the edges of each working section sharp to complete the production of the electrode.

[0018] As a further improvement of the present invention, the “rough 2 fine 3” cutting method in step S4 is as follows: The first rough cutting offset is 0.3mm, the second rough cutting offset is 0.2mm, the third fine cutting offset is 0.18mm, the fourth fine cutting offset is 0.14mm, and the fifth fine cutting offset is 0.1mm.

[0019] Beneficial effects Compared with the prior art, the advantages of the electrode capable of simultaneously processing two square holes and its use and manufacturing method of the present invention are: 1. The electrode has two working parts, so it can process two square holes at the same time, which improves production efficiency and can meet the needs of production tasks; At the same time, since each electrode undergoes rough machining of the square hole in working section a, semi-finishing of the square hole in working section b, finishing of the square hole in working section c, and super-finishing of the square hole in working section d, it can also avoid the square hole internal angle greater than R0.05mm due to the blunting of the edge of the electrode working part, so that the dimensional accuracy, form and position tolerance and other indicators of the part can meet the requirements of the design drawing, thereby ensuring the qualified rate of the part and reducing the processing cost; Moreover, in the past, more than two electrodes would be consumed for each valve body part produced. However, now, only half an electrode is consumed when processing the first valve body part in each batch, and only one electrode is consumed for every two valve body parts processed thereafter, greatly improving the utilization rate of the electrodes.

[0020] 2. This production method can produce electrodes in batches, reducing the production cost of electrodes.

[0021] The present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, which are used to illustrate embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 It is the main view of the valve body part being processed; Figure 2 It is a top view of the valve body part being processed; Figure 3 It is a front view of the electrode in the present invention; Figure 4 It is a left side view of the electrode in the present invention; Figure 5 This is an enlarged front view of the electrode working part of the present invention; Figure 6 It is a cross-sectional view of the working portion of the electrode in the present invention; Figure 7 The front view of the rectangular block fixture for making electrodes; Figure 8 The left side view of the rectangular block fixture for making electrodes; Figure 9 Cross-sectional view of the electrode blank when it is loaded into the rectangular block fixture; Figure 10 This is the main view of the grinding tool; Figure 11 This is the left view of the grinding tool; Figure 12 To find the main view of the core shaft; Figure 13 A top view of the mandrel being fixed on the workbench after being inserted into the valve body part being processed for alignment; Figure 14 is a cross-sectional view of a working section a of an electrode in operation according to an embodiment of the present invention; Figure 15 is a cross-sectional view of the working section b of the electrode in operation according to an embodiment of the present invention; Figure 16 is a cross-sectional view of a working section c of an electrode in operation according to an embodiment of the present invention; Figure 17 2 is a cross-sectional view of the working section d of the electrode in operation in an embodiment of the present invention.

[0024] Among them: 1- cylindrical valve body; 11- axial channel; 12- countersunk hole; 13- square hole; 2- electrode clamping part; 21- electrode working part; 211- working section a; 212- working section b; 213- working section c; 214- working section d; 22- concave groove; 3- rectangular block fixture; 31- blank insertion square hole; 32- pressing screw hole; 33- mounting screw hole; 4- grinding tool; 41- straight slot; 5- centering core shaft; 6- workbench. DETAILED DESCRIPTION

[0025] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; of course, they may also refer to mechanical connections or electrical connections; in addition, they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0028] Example The specific embodiments of the present invention are as follows Figure 3-6 As shown, an electrode capable of processing two square holes at the same time includes an electrode clamping portion 2 with a rectangular sheet structure, and both ends of the short side of the electrode clamping portion 2 are connected to an electrode working portion 21 extending in the same direction as its long side and having a square cross-section. The electrode working portion 21 has the same thickness as the electrode clamping portion 2, and the two are an integrated structure. Among them, the electrode working portion 21 includes a working segment a211, a working segment b212, a working segment c213 and a working segment d214 connected in sequence from its free end to the connection end. In this embodiment, as Figure 6 As shown, working segments a211, b212, c213, and d214 all have identical cross-sectional shapes and sizes, and their edges must be sharp. Furthermore, the electrode material is preferably a specially prepared copper-tungsten alloy, CuW32, due to its higher hardness, improved wear resistance, and resistance to deformation at high temperatures compared to copper electrodes.

[0029] Compared to existing electrodes, the electrode in this embodiment has two working portions 21, located at either end of the short side of the electrode clamping portion 2. This allows simultaneous machining of two square holes 13 on the same straight line, thereby improving valve body component production efficiency and meeting production requirements.

[0030] And, as Figure 5 As shown, a concave groove 22 is provided on the short side of the electrode clamping portion 2 between the two electrode working portions 21. This design prevents the edge of the electrode clamping portion 2 from interfering with the countersunk hole 12 during electrode operation. It also forms a step structure at the connection between the electrode working portion 21 and the electrode clamping portion 2, thereby increasing the strength of the connection between the electrode working portion 21 and the electrode clamping portion 2.

[0031] In addition, in order to enable working section a211, working section b212, working section c213 and working section d214 to complete one stage of punching processing independently, the axial lengths of working section a211, working section b212, working section c213 and working section d214 are not less than the depth of square hole 13.

[0032] Regarding the method of using the electrode of the above structure, Figure 14-17 As shown, it includes the following steps: S1. Install the electrode on the EDM equipment and find the positive electrode; S2. Align the cylindrical valve body 1 to be processed on the workbench and set the countersunk hole 12 on the cylindrical valve body 1 vertically upward; S3. Using an electrospark machining device, move the electrode horizontally to the top of the cylindrical valve body 1, and make the free ends of the two electrode working parts 21 face the two countersunk holes 12 respectively; S4. Rough machining of the square hole 13: Driven by the EDM equipment, the free end faces of the two electrode working parts 21 are gradually fed downward from the upper end face of the countersunk hole 12 until the lower ends of the two working sections a211 respectively penetrate the bottom surfaces of the two countersunk holes 12 and connect to the axial channel 11. During this process, a discharge gap of approximately 0.07 mm is set, and only the working section a211 of the electrode working part 21 performs the discharge work. After completing the rough machining of the square hole 13, the electrode is raised and reset. S5. Semi-finishing of the square hole 13: Driven by the EDM equipment, the free end faces of the two electrode working parts 21 are gradually fed downward from the upper end face of the countersunk hole 12 until the lower ends of the two working sections b212 respectively penetrate the bottom surfaces of the two countersunk holes 12 and reach the axial channel 11. During this process, a discharge gap of approximately 0.12 mm is set, and only the working section b212 of the electrode working part 21 performs the discharge work. After completing the semi-finishing of the square hole 13, the electrode is raised and reset. S6. Through reverse polarity EDM machining, the working segments a211 and b212 of the electrode working portion 21 are self-destroyed, so that the lower end of the working segment c213 becomes the new free end of the electrode working portion 21, leaving enough downward feed space for subsequent machining; S7, Finishing of Square Hole 13: Driven by the EDM equipment, the free end faces of the two electrode working sections 21 are gradually fed downward from the upper end face of the countersunk hole 12 until the lower ends of the two working sections c213 respectively penetrate the bottom surfaces of the two countersunk holes 12 and reach the axial channel 11. During this process, a discharge gap of approximately 0.16 mm is set, and only the working section c213 of the electrode working section 21 performs the discharge work. After finishing the square hole 13, the electrode is raised and reset. S8. Superfinishing the Square Hole 13: Driven by the EDM equipment, the free end faces of the two electrode working sections 21 are gradually fed downward from the upper end face of the countersunk hole 12 until the lower ends of the two working sections d214 respectively penetrate the bottom surfaces of the two countersunk holes 12 and reach the axial channel 11. During this process, a discharge gap of approximately 0.19 mm is set, and only the working section d214 of the electrode working section 21 performs the discharge operation. After the superfinishing of the square hole 13 is completed, the electrode is raised and reset, completing the simultaneous machining of the two square holes 13 of the first cylindrical valve body 1. S9. After the processing is completed, only the finished cylindrical valve body 1 is removed, and the electrode is not removed. Then the next cylindrical valve body 1 is clamped and aligned according to the previous steps S2 and S3, and the working segment c213 of the old electrode is continued to be used to perform rough processing of the square hole 13 of the new cylindrical valve body 1, and the working segment d214 of the old electrode is used to perform semi-finishing processing of the square hole 13 of the new cylindrical valve body 1; after the semi-finishing processing of the square hole 13 is completed, a new electrode is replaced and the electrode is aligned according to the steps of S1, and the working segment a211 of the new electrode is used for fine processing, and the working segment b212 of the new electrode is used for super-finishing processing. Repeat this cycle to achieve continuous production of the cylindrical valve body 1.

[0033] Compared with the current method of consuming more than two electrodes for each valve body part produced, after adopting step S9, only half an electrode will be consumed when processing the first zero valve body part of each batch of valve body parts, and only one electrode will be consumed for every two valve body parts processed thereafter, which greatly improves the utilization rate of the electrodes.

[0034] Wherein, step S1 is specifically as follows: After the electrode is vertically clamped on the Z axis of the EDM equipment through the electrode clamping part 2, the positive electrode working part 21 is found with a micrometer so that the total runout of each vertical surface of the electrode is 0.001 mm.

[0035] Step S2 specifically includes the following steps: S2.1. Use a dial indicator to align the horizontal surface of the workbench 6 so that the horizontal surface runout of the workbench 6 is 0.001mm; S2.2, such as Figure 13 As shown, the aligning core shaft 5 is inserted into the axial channel 11 of the cylindrical valve body 1, and the cylindrical valve body 1 is pressed and fixed on the workbench 6 by fixing the end of the aligning core shaft 5 so that the countersunk hole 12 on the cylindrical valve body 1 is vertically facing upward; S2.3. Use a micrometer to align the busbars on both ends of the core shaft 5, ensuring that the total runout is 0.001mm. Then, use an electrode to electrically induct the core shaft 5 to complete the front and back centering. Use an electrode to electrically induct the two end surfaces of the cylindrical valve body 1 to complete the left and right centering. This completes the alignment of the cylindrical valve body 1. S2.4. Remove the aligning core shaft 5 and prepare to process the cylindrical valve body 1.

[0036] In this embodiment, in order to facilitate the alignment of the cylindrical valve body 1, the flatness of the workbench 6 is 0.001 mm. At the same time, according to the characteristics of the valve body parts, the following are selected: Figure 12 The alignment mandrel 5 is made of stainless steel, has a cylindricity of 0.001 mm, and has a clearance fit of 0.001 mm between the alignment mandrel 5 and the axial passage 11 of the valve body being processed. The alignment mandrel 5 is manufactured using precision machining methods.

[0037] In addition, step S6 is specifically as follows: A flat plate made of the same material as the electrode working part 21 is fixed horizontally on the workbench 6. The parallelism of the thickness surface of this flat plate is 0.01 mm. When the electrode self-destruction is required, the polarity of the EDM equipment is changed, the pulse width and discharge gap are adjusted, and then the electrode working part 21 is used to perform EDM on the flat plate to remove the used working part of the electrode working part 21.

[0038] In this embodiment, step S6 is performed because the diameter of the axial passage 11 of the cylindrical valve body 1 is generally small. If the electrode's working section c213 is used for finish machining directly while the electrode's working portion 21 is advanced further, this would cause discharge corrosion between the electrode's working section a211 and the lower wall of the axial passage 11. Therefore, prior to finish machining, reverse-polarity EDM machining is required to remove both working sections a211 and b212 of the electrode's working portion 21.

[0039] In the above-mentioned method of using the electrode, since each electrode performs rough machining of the square hole 13 through the working section a211, semi-finishing of the square hole 13 through the working section b212, finishing of the square hole 13 through the working section c213, and super-finishing of the square hole 13 through the working section d214, it is also possible to avoid the inner angle of the square hole 13 being greater than R0.05mm due to the blunting of the edges of the working part of the electrode, so that the dimensional accuracy, form and position tolerance and other indicators of the part can meet the requirements of the design drawing, thereby ensuring the qualified rate of the part and reducing the processing cost.

[0040] In addition, the method for manufacturing the electrode includes the following steps: S1, prepare rectangular block fixture 3, and Figure 9 As shown, six blanks are fixed on a rectangular block fixture 3 in two parallel rows, and the blanks are pressed by screws so that a section of the blank is overhanging at one end as the processed section; S2, connect the rectangular block fixture 3 to the 3R fixture on the wire cutting processing equipment; S4. Programming a cutting path using a wire cutting machine so that the wire cutting path sequentially passes through the processing segments on a row of blanks, thereby cutting the processing segments of the six blanks into the shape of electrodes at one time. The "rough 2 and fine 3" method is used for cutting, and five cutting passes are performed to obtain a semi-finished electrode with a grinding allowance. S5. Rotate the special fixture 90° clockwise or counterclockwise, cut the blank along the thickness direction, and slice the blank into two electrodes along the thickness direction. When cutting, use the same "rough 2 and fine 3" method, perform 5 cuts, and retain grinding allowance; S6, cutting the processing section of the blank to obtain 12 semi-finished electrodes; S7, extract the remaining blanks by translation, feed the blanks, and repeat the steps of S4 and S5 until the blanks are fully utilized, thereby obtaining a batch of semi-finished electrodes; S8, choose Figure 10 、 11 The grinding tool 4 shown has a groove 41 on its surface. The depth of the groove 41 is 0.1 mm less than the thickness of the semi-finished electrode, and the flatness of the bottom surface of the groove 41 is 0.001 mm. S9. Place the semi-finished electrode flatly in the slot 41 of the grinding tool 4, grind the two thickness surfaces of the electrode, then take out the semi-finished electrode and grind the edge side of the electrode so that the shape and position tolerance and dimensional accuracy of the electrode meet the design requirements, while keeping the edges of each working section sharp, and complete the production of the electrode.

[0041] The manufacturing method can produce electrodes in batches, thereby reducing the production cost of the electrodes.

[0042] In this embodiment, the "rough 2 fine 3" cutting method in step S4 is as follows: The first rough cutting offset is 0.3mm, the second rough cutting offset is 0.2mm, the third fine cutting offset is 0.18mm, the fourth fine cutting offset is 0.14mm, and the fifth fine cutting offset is 0.1mm.

[0043] As for the specific structure of the rectangular block fixture 3, Figure 7 、 8 As shown, one side of the rectangular block fixture 3 is provided with two rows, one above the other, of six blank insertion holes 32. Furthermore, three sets of clamping screw holes 32 are provided on the rectangular block fixture 3 on opposite sides of the two rows of blank insertion holes 32. Each set of clamping screw holes 32 communicates with one of the blank insertion holes 32. Furthermore, mounting screw holes 33 are provided on the side of the rectangular block fixture 3 away from the free end of the blank.

[0044] The present invention has been described above in conjunction with the best embodiments, but the present invention is not limited to the embodiments disclosed above, but should cover various modifications and equivalent combinations based on the essence of the present invention.

Claims

1. An electrode capable of processing two square holes simultaneously, characterized in that: The invention comprises an electrode clamping portion (2) having a rectangular sheet structure, wherein both ends of a short side of one side of the electrode clamping portion (2) are connected to an electrode working portion (21) extending in the same direction as the long side thereof and having a square cross-section. The electrode working portion (21) comprises a working segment a (211), a working segment b (212), a working segment c (213), and a working segment d (214) which are sequentially connected in a direction from the free end to the connection end thereof.

2. The electrode capable of simultaneously processing two square holes according to claim 1, characterized in that: A concave groove (22) is provided on the short side of the electrode clamping portion (2) between the two electrode working portions (21).

3. The electrode capable of simultaneously processing two square holes according to claim 1, characterized in that: The electrode working portion (21) and the electrode clamping portion (2) have the same thickness, and both are an integrated structure.

4. The electrode capable of simultaneously processing two square holes according to claim 1, characterized in that: The axial lengths of the working section a (211), the working section b (212), the working section c (213), and the working section d (214) are not less than the depth of the square hole (13).

5. A method for using the electrode according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Install the electrode on the EDM equipment and find the positive electrode; S2. Align the cylindrical valve body (1) to be processed on the workbench, and set the countersunk hole (12) on the cylindrical valve body (1) vertically upward; S3. Using an electrospark machining device, move the electrode horizontally to the top of the cylindrical valve body (1), and make the free ends of the two electrode working parts (21) face the two countersunk holes (12) respectively; S4, rough machining of the square hole (13): driven by the electric discharge machining equipment, the free end faces of the two electrode working parts (21) are gradually fed downward from the upper end face of the countersunk hole (12) until the lower ends of the two working sections a (211) respectively penetrate the bottom faces of the two countersunk holes (12) and connect to the axial channel (11). During this process, only the working section a (211) in the electrode working part (21) performs the discharge work, and after completing the rough machining of the square hole (13), the electrode is raised and reset; S5. Semi-finishing of the square hole (13): Driven by the electric discharge machining equipment, the free end faces of the two electrode working parts (21) are gradually fed downward from the upper end face of the countersunk hole (12) until the lower ends of the two working sections b (212) respectively penetrate the bottom faces of the two countersunk holes (12) and reach the axial channel (11). During this process, only the working section b (212) in the electrode working part (21) performs the discharge work, and after completing the semi-finishing of the square hole (13), the electrode is raised and reset; S6, through the reverse polarity electrospark machining, the working section a (211) and the working section b (212) of the electrode working part (21) are self-destructed, so that the lower end of the working section c (213) becomes the new free end of the electrode working part (21), leaving enough downward feed space for subsequent machining; S7, finishing of the square hole (13): driven by the electric spark machining equipment, the free end faces of the two electrode working parts (21) are gradually fed downward from the upper end face of the countersunk hole (12) until the lower ends of the two working sections c (213) respectively penetrate the bottom faces of the two countersunk holes (12) and reach the axial channel (11). During this process, only the working section c (213) in the electrode working part (21) performs the discharge work, and after finishing the square hole (13), the electrode is raised and reset; S8, superfinishing of square hole (13): driven by the electric discharge machining equipment, the free end faces of the two electrode working parts (21) are gradually fed downward from the upper end face of the countersunk hole (12) until the lower ends of the two working sections d (214) respectively penetrate the bottom faces of the two countersunk holes (12) and reach the axial channel (11). During this process, only the working section d (214) in the electrode working part (21) performs discharge work, and after completing the superfinishing of the square hole (13), the electrode is raised and reset, completing the synchronous machining of the two square holes (13) of the first cylindrical valve body (1); S9. After the processing is completed, only the finished cylindrical valve body (1) is removed without removing the electrode. Then, the next cylindrical valve body (1) is clamped and aligned according to the previous steps S2 and S3, and the working section c (213) of the old electrode is continued to be used to perform rough processing of the square hole (13) of the new cylindrical valve body (1), and the working section d (214) of the old electrode is used to perform semi-finishing processing of the square hole (13) of the new cylindrical valve body (1); after the semi-finishing processing of the square hole (13) is completed, a new electrode is replaced and the electrode is aligned according to the steps of S1, and the working section a (211) of the new electrode is used for finishing processing, and the working section b (212) of the new electrode is used for super-finishing processing. This reciprocating cycle can realize the continuous production of cylindrical valve bodies (1).

6. The method for using the electrode according to claim 5, characterized in that: Step S1 is specifically as follows: After the electrode is vertically clamped on the Z axis of the electrospark machining equipment through the electrode clamping part (2), the positive electrode working part (21) is located using a micrometer so that the total runout of each vertical surface of the electrode is 0.001 mm.

7. The method for using the electrode according to claim 5, characterized in that: Step S2 specifically includes the following steps: S2.

1. Use a micrometer to align the horizontal surface of the workbench (6) so that the horizontal surface runout of the workbench (6) is 0.001 mm; S2.

2. Insert the alignment core shaft (5) into the axial passage (11) of the cylindrical valve body (1), and press and fix the cylindrical valve body (1) on the workbench (6) by fixing the end of the alignment core shaft (5) so that the countersunk hole (12) on the cylindrical valve body (1) is vertically upward; S2.

3. Use a micrometer to align the busbars at the left and right ends of the core shaft (5) to ensure that the total runout is 0.001 mm. Then, use an electrode to electrically induct the core shaft (5) to complete the front and rear centering, and use an electrode to electrically induct the two end surfaces of the cylindrical valve body (1) to complete the left and right centering, and the cylindrical valve body (1) can be aligned. S2.

4. Remove the alignment core shaft (5) and prepare to process the cylindrical valve body (1).

8. The method for using the electrode according to claim 5, characterized in that: Step S6 is specifically as follows: A flat plate made of the same material as the electrode working part (21) is fixedly placed horizontally on the workbench (6). The parallelism of the thickness of the flat plate is 0.01 mm. When the electrode self-destruction is required, the polarity of the electric spark equipment is changed, the pulse width and the discharge gap are adjusted, and then the electrode working part (21) is used to perform electric spark machining on the flat plate to remove the used working part of the electrode working part (21).

9. A method for manufacturing an electrode according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Prepare a rectangular block fixture (3), insert and fix 6 blanks in two parallel rows on the rectangular block fixture (3), and press the blanks with screws so that one end of the blank is suspended for a section to be processed; S2, connecting the rectangular block fixture (3) to the 3R fixture on the wire cutting processing equipment; S4. Programming a cutting path using a wire cutting machine so that the wire cutting path sequentially passes through the processing segments on a row of blanks, thereby cutting the processing segments of the six blanks into the shape of electrodes at one time. The "rough 2 and fine 3" method is used for cutting, and five cuts are performed to obtain a semi-finished electrode with a grinding allowance. S5. Rotate the special fixture 90° clockwise or counterclockwise, cut the blank along the thickness direction, and slice the blank into two electrodes along the thickness direction. When cutting, use the same "rough 2 and fine 3" method, perform 5 cuts, and retain grinding allowance; S6, cutting the processing section of the blank to obtain 12 semi-finished electrodes; S7, extract the remaining blanks by translation, feed the blanks, and repeat the steps of S4 and S5 until the blanks are fully utilized, thereby obtaining a batch of semi-finished electrodes; S8, selecting a grinding tool (4) with a slot (41) on the surface, wherein the depth of the slot (41) is 0.1 mm less than the thickness of the semi-finished electrode, and the flatness of the bottom surface of the slot (41) is 0.001 mm; S9. Place the semi-finished electrode flatly in the slot (41) of the grinding tool (4), grind the two thickness surfaces of the electrode, then take out the semi-finished electrode and grind the edge side of the electrode so that the shape and position tolerance and dimensional accuracy of the electrode meet the design requirements, and at the same time keep the edges of each working section sharp, thus completing the production of the electrode.

10. The method for manufacturing an electrode according to claim 9, wherein: The specific cutting method of "rough 2 fine 3" in step S4 is as follows: The first rough cutting offset is 0.3mm, the second rough cutting offset is 0.2mm, the third fine cutting offset is 0.18mm, the fourth fine cutting offset is 0.14mm, and the fifth fine cutting offset is 0.1mm.

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