Method and system for machining female die of special-shaped blanking die

Abstract

The invention discloses a method and a system for machining a female die of a special-shaped blanking die. The method comprises the following steps: machining an inner hole and a maximum outline excircle of a hollow cylinder by utilizing a numerical control lathe; the two end faces of the machined hollow cylinder are polished so that the two end faces of the hollow cylinder can be parallel; the outer wall of the hollow cylinder is milled with the ground bottom face of the hollow cylinder as the standard, a conical face cutting edge is obtained, and the conical face cutting edge is located on one side of the hollow cylinder; the milled hollow cylinder is subjected to vacuum quenching and ice-cooling treatment; and the two end faces of the hollow cylinder subjected to ice-cooling treatment are finely ground through a surface grinding machine. According to the method, through a numerical control turning procedure, when the inner shape of the cutting edge of the female die is machined, allowance is reserved, the wall thickness of the cutting edge of the female die is indirectly increased, the strength of the cutting edge is guaranteed, and the quality and the machining precision of the taper of the cutting edge machined by a numerical control coordinate grinding machine are guaranteed; and in the heat treatment process, the quenching hardness of the material is improved, so that the female die has higher hardness, and the sharpness and the wear resistance of the cutting edge are improved.

Description

Technical Field

[0001] The invention belongs to the field of aviation equipment assembly die processing, and in particular relates to a method and system for processing a concave die of a heterogeneous punching die. Background Art

[0002] The film seal on the engine is made by a die. Since there is cotton silk in the film part, during the punching process, if the die cutting edge is of poor quality, broken or not sharp, the silk will be easily pulled or burred during the punching process, causing the film part to be scrapped. If this happens, the film will become waste and cannot be used. If the die cutting edge is not in the same plane, the high side of the cutting edge will contact the film part first, and the low side will contact later, which will cause the film part to be deformed after punching, and the size will be unqualified, causing the film part to be scrapped.

[0003] Therefore, in order to ensure the qualified rate of the special-shaped film parts, it is necessary to ensure that the die of the punching die has sharp and uniform punching edges, and at the same time, all the edges must be in the same plane. The die is made of high-strength, high-hardness, high-toughness and high-pressure-resistant materials. In the processing process of the existing process method, stress will appear in the die after heat treatment, and stress deformation will occur during the finishing process of CNC milling, wire cutting and other processes; during wire cutting and CNC milling, there is a reference alignment error between the two processes, which will cause a large angle error of the die. After processing, the die edge profile will have an angle offset, resulting in an offset of the die edge profile; at the same time, if there is a distance error between the center of the part, the die edge profile will also be offset. When the die edge profile is offset, the die edge after finishing will have a drop, so that the edge is not on the same height plane. When the die punches the film parts, it will cause the film parts to deform, resulting in unqualified film parts. After heat treatment, CNC milling will be used to process the die cutting edge. Carbide milling cutters will be used. The radius of the milling cutter is smaller than the radius of the smallest arc in the special-shaped contour. The contour is followed to perform layered processing. To ensure the accuracy requirements of the die cutting edge and the 20° cone surface, the layered processing depth must be less than or equal to 0.01mm. The milling program capacity is large, the milling processing time is long, and the processing efficiency is low. In addition, due to the high hardness of the material and the small diameter of the tool, the cutting heat generated during milling is large, which can easily cause part annealing and tool wear. Once the milling cutter blade is worn, it cannot be used anymore and needs to be scrapped and replaced with a new tool for continued processing. The tool cost is high. Finally, when milling to the cutting edge, the workpiece wall becomes thinner and thinner. Due to the influence of the cutting force of the tool, the cutting edge is prone to chipping, breakage or deformation, resulting in poor quality of the die cutting edge. Ultimately, qualified film parts cannot be punched out, and the film punching pass rate is low. When the milling cutter approaches the cutting edge, the cutting edge is affected by the cutting force, and is prone to chipping, breakage or deformation, affecting the film punching pass rate. Summary of the invention

[0004] The purpose of the present invention is to provide a method and system for processing a concave die of a special blanking die, so as to solve the technical defects in the prior art that the cutting edge may be chipped, damaged, deformed, and have different heights, and the processing efficiency is low during the processing of the concave die.

[0005] To achieve the above object, the present invention adopts the following scheme: In a first aspect, a method for processing a concave die of a special blanking die is provided, comprising: Use CNC lathe to process the inner hole and the outer circle with the maximum contour of the hollow cylinder; Grinding the two end surfaces of the processed hollow cylinder to make the two end surfaces of the hollow cylinder parallel; Taking the polished bottom surface of the hollow cylinder as a reference, the outer wall of the hollow cylinder is milled to obtain a conical cutting edge, wherein the conical cutting edge is located on one side of the hollow cylinder; The milled hollow cylinder is vacuum quenched and ice-cooled; Fine grinding the two end surfaces of the hollow cylinder after the ice-cold treatment by a surface grinder; Based on CNC coordinate grinding, the hollow cylinder is processed; The hollow cylinder processed by the CNC coordinate grinding is subjected to plunge grinding and contour grinding; The hollow cylinder is cut by slow wire cutting, and the conical cutting edge is polished to obtain a concave die.

[0006] Further, the inner hole and the outer circle with the largest contour of the hollow cylinder are processed by using a numerically controlled lathe, wherein the inner hole is processed with a processing allowance of 4 mm to 6 mm reserved according to the minimum diameter of the cutting edge contour; The maximum outer circle of the contour reserves a machining allowance of 0.5mm~2mm according to the maximum outer circle of the cutting edge contour, and the verticality between the end face of the hollow cylinder and the inner hole is less than or equal to 0.02mm for machining, and ensures that the maximum outer circle of the contour is coaxial with the inner hole.

[0007] Furthermore, the step of grinding the two end faces of the processed hollow cylinder to make the two end faces of the hollow cylinder parallel includes: Use a surface grinder to grind the two end surfaces of the hollow cylinder to ensure that the two end surfaces of the hollow cylinder are parallel to 0.009~0.02mm.

[0008] Furthermore, the outer wall of the hollow cylinder is milled based on the ground bottom surface of the hollow cylinder to obtain a conical cutting edge, wherein the conical cutting edge is located on one side of the hollow cylinder, and specifically includes: Taking the polished bottom surface of the hollow cylinder as a reference, a CNC milling machine is used to flatten the outer contour of the hollow cylinder through a one-time clamping and milling process, so that the outer wall of the hollow cylinder has a conical cutting edge.

[0009] Further, the hollow cylinder after milling is subjected to vacuum quenching and ice cooling treatment, specifically including: A vacuum furnace is used to vacuum quench the hollow cylinder after milling, so that the hardness of the hollow cylinder reaches HRC58-62, and the deformation of the hollow cylinder is less than or equal to 0.02mm; At the same time, the hollow cylinder after vacuum quenching is subjected to ice cooling treatment.

[0010] Further, fine grinding the two end surfaces of the hollow cylinder after the ice-cold treatment by a surface grinder specifically includes: The two end faces of the hollow cylinder are processed by surface grinding to eliminate the deformation caused by quenching so that the surface roughness of the hollow cylinder reaches Ra0.2.

[0011] Furthermore, based on CNC coordinate grinding, the hollow cylinder is processed, specifically including: Install the hollow cylinder on the magnetic table of the CNC coordinate grinder, straighten the process flatness, and align the inner hole of the hollow cylinder.

[0012] Further, the hollow cylinder after the CNC coordinate grinding is subjected to plunge grinding and contour grinding, specifically including: Use CBN grinding wheel to grind the outer wall and conical edge of the hollow cylinder by plunge grinding and contour cutting. In the process of plunge grinding, the bottom surface of the hollow cylinder after flat grinding is used as the reference, and the grinding wheel is plunged up and down along the taper direction of the conical cutting edge, and the feed speed is 3HZ; During the contour cutting process, the grinding wheel cuts along the contour of the conical cutting edge of the hollow cylinder, and feeds clockwise for the outer contour of the hollow cylinder and counterclockwise for the inner contour of the hollow cylinder.

[0013] Further, the hollow cylinder is cut by wire cutting, and the conical cutting edge is polished to obtain a concave die, which specifically includes: Through multiple slow wire cutting, ensure that the diameter of the inner hole meets the requirements and obtain the concave die.

[0014] In a second aspect, a system for processing a concave die of a special-shaped blanking die is provided, comprising: Processing module, used for processing the inner hole and the outer circle with the maximum contour of the hollow cylinder; A grinding module is used to grind the two end surfaces of the hollow cylinder to make the two end surfaces of the hollow cylinder parallel; A milling module, used for milling the outer wall of a hollow cylinder; Quenching module: used for vacuum quenching of hollow cylinders after milling; Ice-cooling treatment module, used to cool the hollow cylinder after vacuum quenching; Cutting module, used for cutting hollow cylinders.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This method uses the CNC lathe process to leave a 5mm margin when processing the inner shape of the die cutting edge, which indirectly increases the wall thickness of the die cutting edge, ensures the strength of the cutting edge, and ensures the quality and processing accuracy of the cutting edge taper processed by the CNC coordinate grinder; in the heat treatment process, the material quenching hardness is increased to ensure that the die has a higher hardness, thereby improving the sharpness and wear resistance of the cutting edge. At the same time, the cold treatment of the parts is increased, which effectively reduces the deformation during the heat treatment process, reduces the material processing stress, avoids deformation during the cutting edge processing process, and improves the processing qualification rate; through the finishing process, the taper of the die cutting edge is ground first, and after ensuring the cutting edge accuracy, the cutting of the inner shape of the cutting edge is performed, which avoids the problems of chipping, breakage, deformation and different cutting edge heights during the cutting edge processing, and improves the processing qualification rate.

[0016] 2. Use 5-axis linkage processing of CNC coordinate grinder, especially the integrated cutting method of plunge grinding and contour cutting, and the feed F1 per unit time during plunge grinding is greater than the feed F2 per unit time during contour cutting, which improves the grinding efficiency and grinding quality of the conical surface.

[0017] 3. By selecting CBN grinding wheels with better cutting performance, the grinding wheel wear is small, the dimensional stability is high, and the universal straight grinding wheel is used to achieve efficient grinding of tapers, the processing efficiency can be improved, and the processing cost can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A flow chart of the method for processing the concave die of a special blanking die provided by the present invention; Figure 2 It is the cross-sectional view of the film part; Figure 3 It is the top view of the film part; Figure 4 It is the cross-sectional view of the die; Figure 5 It is a schematic diagram of punching film with a concave die; Figure 6 This is a schematic diagram of the chipping of the cutting edge of the die when punching a film; Figure 7This is a schematic diagram of the blunt edge of the die when punching the film; Figure 8 This is a schematic diagram showing that the punching edges of the die are not in the same plane; Fig. 9 Schematic diagram of film deformation; Fig.10 Schematic diagram of the taper of the die edge; Fig.11 The first schematic diagram of the angle deviation of the die edge contour; Fig.12 The second schematic diagram of the angle offset of the die edge contour; Fig.13 Schematic diagram of the die edge drop; Fig.14 This is a schematic diagram of the chipping of the die cutting edge; Fig.15 This is a schematic diagram of CNC machining of hollow cylinders; Fig.16 This is the first schematic diagram of CNC milling of hollow cylinder; Fig.17 The second schematic diagram of CNC milling of hollow cylinder; Fig.18 It is a schematic diagram of the flat grinding process of a hollow cylinder; Fig.19 It is a schematic diagram of the hollow cylindrical coordinate grinding process; Fig. 20 This is a schematic diagram of a CNC coordinate grinding machine; Fig.21 is a schematic diagram of a grinding wheel; Fig. 22 is the first grinding schematic diagram; Fig.23 is the second grinding schematic diagram; Fig.24 This is a schematic diagram of slow wire cutting; Fig.25 This is the schematic diagram of the processing system of the concave die of the special blanking die; Among them: 1. Film; 2. Die; 3. Chipped edge; 4. Wiredrawing; 5. Blurred cutting edge; 6. Burrs; 7. Maximum contour outer circle; 8. Die cutting edge contour; 9. Inner hole; 10. Process flatness; 11. Outer contour cutting edge; 12. Milling area; 13. Magnetic table; 14. Workbench; 15. Spindle; 16. Grinding wheel; 17. Grinding wheel rod; 18. First cutting; 19. Second cutting; 20. Third cutting. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0023] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0024] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] like Figure 2-Figure 3 As shown, the film 1 seal on the engine is made by a concave mold 2, such as Figure 4 and Figure 5 As shown; due to the presence of cotton silk in the film 1 part, during the punching process, if the edge quality of the die 2 is not good, such as Figure 6 and Figure 7 As shown, the edge is broken 3 or the edge is not sharp 5, and the silk is easily drawn 4 or burrs 6 appear during the punching process, causing the film 1 parts to be scrapped. If this happens, the film 1 becomes a waste and cannot be used. Figure 8 and Fig. 9As shown, if the cutting edge of the die 2 is not in the same plane, the higher side of the cutting edge will contact the film 1 part first, and the lower side will contact later, which will cause the film 1 part to be deformed after punching, and the size will be unqualified, causing the film 1 part to be scrapped.

[0026] Therefore, in order to ensure the qualified rate of the special-shaped film 1 parts, it is necessary to ensure that the die 2 of the punching die has a sharp and uniform punching edge, and at the same time ensure that all the edges are in the same plane, such as Fig.10 As shown. The die 2 is made of a material with high strength, high hardness, high toughness and high pressure resistance. In the processing of the existing process method, stress will appear in the die 2 after heat treatment. During the finishing process of CNC milling, wire cutting and other processes, stress deformation will occur. During the wire cutting process and CNC milling process, there is a reference alignment error between the two processes, which will cause a large angle error of the die 2. After processing, the die edge profile 8 will have an angle deviation, resulting in the die edge profile 8 being offset, as shown in FIG. Fig.11 At the same time, if there is a distance error between the center of the part, the die edge profile 8 will also be offset, such as Fig.12 As shown; when the die cutting edge profile 8 is offset, the die cutting edge 2 will have a drop after finishing, such as Fig.13 As shown, the cutting edges are not on the same height plane. When the die 2 punches the film 1 part, the film 1 part will be deformed, causing the film 1 part to be unqualified. After heat treatment, a carbide milling cutter will be selected for CNC milling of the die cutting edge. The radius of the milling cutter is smaller than the radius of the smallest arc in the special-shaped contour. The layered processing is carried out by following the contour. To ensure the accuracy requirements of the die cutting edge and the 20° cone surface, the layered processing depth must be less than or equal to 0.01mm. The milling program capacity is large, the milling processing time is long, and the processing efficiency is low. In addition, due to the high hardness of the material and the small tool diameter, the cutting heat generated during milling is large, which can easily cause part annealing and large tool wear. Once the milling cutter blade is worn, it cannot be used anymore and needs to be scrapped and replaced with a new tool for continued processing. The tool cost is high. Finally, when milling to the cutting edge, the workpiece wall becomes thinner and thinner. Due to the influence of the cutting force of the tool, the cutting edge is prone to chipping 3, breakage or deformation, resulting in poor quality of the cutting edge of the die 2. Ultimately, qualified film 1 parts cannot be punched out, and the qualified rate of film 1 punching is low. When the milling cutter approaches the cutting edge, the cutting edge is affected by the cutting force, which is prone to chipping 3, breakage or deformation, affecting the qualified rate of film 1 punching, such as Fig.14 shown.

[0027] In order to solve the above technical defects, the inventor provides a method and system for processing a concave die of a special blanking die.

[0028] The present invention is further described in detail below with reference to the accompanying drawings.

[0029] like Figure 15-Figure 24 As shown, in a first aspect of an embodiment of the present invention, a method for processing a concave die of a special blanking die is provided, the method comprising: S101, using a CNC lathe to process the inner hole and the outer circle of the maximum contour of the hollow cylinder; for example, Fig.15 As shown, the inner hole 9 and the maximum contour outer circle 7 of the hollow cylinder are processed by a CNC lathe, wherein the inner hole 9 is processed with a processing allowance of 4mm~6mm according to the minimum diameter of the cutting edge contour; the maximum contour outer circle 7 is processed with a processing allowance of 0.5mm~2mm according to the maximum outer circle of the cutting edge contour, and the verticality between the end face of the hollow cylinder and the inner hole 9 is less than or equal to 0.02mm, and it is ensured that the maximum contour outer circle 7 is coaxial with the inner hole 9 by 0.02mm.

[0030] S102, grinding the two end surfaces of the processed hollow cylinder to make the two end surfaces of the hollow cylinder parallel; illustratively, using a surface grinder, grinding the two end surfaces of the hollow cylinder to ensure that the two end surfaces of the hollow cylinder are parallel by 0.009~0.02mm.

[0031] S103, taking the polished bottom surface of the hollow cylinder as a reference, milling the outer wall of the hollow cylinder to obtain a conical cutting edge, wherein the conical cutting edge is located on one side of the hollow cylinder; Fig.16 and Fig.17 As shown, exemplarily, taking the polished bottom surface of the hollow cylinder as a reference, a CNC milling machine is used to clamp and mill the flat and hollow cylindrical contour cutting edge 11, the step area and the milling area 12 in one process, the cutting edge is 20°, and the conical surface is evenly ground with 0.2mm~0.3mm, so that the outer wall of the hollow cylinder has a conical cutting edge.

[0032] S104, vacuum quenching and cooling the hollow cylinder after milling; illustratively, a vacuum furnace is used to vacuum quench the hollow cylinder after milling, so that the hardness of the hollow cylinder reaches HRC58-62, and the deformation of the hollow cylinder is less than or equal to 0.02mm; at the same time, the hollow cylinder after vacuum quenching is cooled to reduce subsequent processing stress deformation.

[0033] S105, fine grinding the two end surfaces of the hollow cylinder after the ice-cold treatment by a surface grinder; Fig.18 As shown, illustratively, the two end faces of the hollow cylinder are finely ground by a surface grinder to eliminate the deformation caused by the quenching treatment, so that the surface roughness of the hollow cylinder reaches Ra0.2 and the parallelism is less than or equal to 0.01mm.

[0034] S106, processing the hollow cylinder based on CNC coordinate grinding; Fig.19As shown, for example, the hollow cylinder is mounted on the magnetic table 13 of the CNC coordinate grinder, the process flat 10 is straightened, and the inner hole 9 of the hollow cylinder is aligned. First, the inner hole 9 and the process flat 10 are ground, and the clamping is completed in one time to ensure that the cylindricality of the inner hole 9 is 0.005mm, and the process flat 10 is axially parallel and perpendicular to the inner hole 9 by 0.005mm.

[0035] S107, the hollow cylinder processed by the CNC coordinate grinding is subjected to plug grinding and contour cutting. For example, a CNC coordinate grinding is selected. During processing, the die 2 is sucked on the magnetic table 13, the process flat 10 is straightened, and the inner hole 9 is aligned. The inner hole 9 and the process flat 10 are ground first, and the clamping is completed in one time to ensure that the cylindricality of the inner hole 9 is 0.005mm, and the process flat 10 is axially parallel to the inner hole 10 and perpendicular to it by 0.005mm. The plug grinding and contour cutting are realized by the linkage control of the five motion axes of the CNC coordinate grinder, namely, the X-axis, the Y-axis, the C-axis, the U-axis, and the Z-axis. Fig. 20 As shown; the contour cutting is realized by using the X-axis, Y-axis and C-axis along the contour of the die cutting edge 8, the grinding wheel 16 is installed on the spindle 15 through the grinding wheel rod 17, and the upper and lower plunge grinding of the grinding wheel 16 is realized by using the U-axis and the Z-axis along the 20° cone direction. While the contour cutting is being performed, the upper and lower plunge grinding is performed to realize 5-axis linkage grinding, with high machining accuracy, good dimensional stability and high machining efficiency. The tool selected is a CBN grinding wheel 16 with a grain size of 200 grains, because the CBN grinding wheel is wear-resistant, has low wear, and has stable grinding dimensions. The cutting force is stronger than that of the milling cutter with the same diameter, and the cutting effect is better; in the above-mentioned grinding wheel 16 parameter setting, the radius of the grinding wheel 16 needs to be smaller than the smallest concave arc radius in the contour of the special-shaped die 2. The smallest concave arc radius in the part shape is 3mm, so the radius of the grinding wheel 16 needs to be less than 3mm. Now a CBN grinding wheel 16 with a radius of 2.5mm is selected, as shown Fig.21 shown.

[0036] The grinding process involved in this step, such as Fig. 22 and Fig.23 As shown, with the bottom surface after flat grinding as the reference, the grinding wheel 16 is inserted and ground up and down along the 20° taper of the die cutting edge, and the feed speed F1 is about 3HZ. At the same time, the grinding wheel moves along the contour 8 of the die cutting edge. To improve the grinding effect, when moving along the contour 8 of the die cutting edge, the outer contour is fed clockwise, and the inner contour is fed counterclockwise. When grinding this part, the contour moving mode is selected to be clockwise, and the feed F2 is 35-40mm / min, and it is a constant speed feed. At this time, F1 per unit time must be greater than F2 per unit time, ensuring that when moving along the contour, at the same contour position, the grinding wheel grinds the 20° cone surface and completes at least one grinding, thereby ensuring the grinding quality and grinding efficiency.

[0037] S108, cutting the hollow cylinder by wire cutting, and grinding the tapered edge to obtain a concave die. Fig.24 As shown, exemplarily, slow wire cutting is performed to straighten the process flat ground in step 6, to align the inner hole ground in step 6, with the alignment error controlled within 0.002mm, to roughly cut the inner mold to remove the 5mm margin left by the CNC lathe process, leaving a margin of 0.2mm-0.3mm, to semi-finely cut the inner mold to leave a margin of 0.03mm-0.05mm, to finely cut the inner mold to leave a margin of 0.002mm-0.003mm, and through the first cutting 18, the second cutting 19 and the third cutting 20, the three cuttings ensure the inner mold size accuracy and surface roughness Ra0.2.

[0038] In the second aspect, this embodiment provides a system for processing a concave die of a special blanking die, such as Fig.25 As shown, including: Processing module, used for processing the inner hole and the outer circle with the maximum contour of the hollow cylinder; A grinding module is used to grind the two end surfaces of the hollow cylinder to make the two end surfaces of the hollow cylinder parallel; A milling module, used for milling the outer wall of a hollow cylinder; Quenching module: used for vacuum quenching of hollow cylinders after milling; Ice-cooling treatment module, used to cool the hollow cylinder after vacuum quenching; Cutting module, used for cutting hollow cylinders.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A method for processing a concave die of a special blanking die, characterized in that: include: Use CNC lathe to process the inner hole and the outer circle with the maximum contour of the hollow cylinder; Grinding the two end surfaces of the processed hollow cylinder to make the two end surfaces of the hollow cylinder parallel; Taking the polished bottom surface of the hollow cylinder as a reference, the outer wall of the hollow cylinder is milled to obtain a conical cutting edge, wherein the conical cutting edge is located on one side of the hollow cylinder; The milled hollow cylinder is vacuum quenched and ice-cooled; Fine grinding the two end surfaces of the hollow cylinder after the ice-cold treatment by a surface grinder; Based on CNC coordinate grinding, the hollow cylinder is processed; The hollow cylinder processed by the CNC coordinate grinding is subjected to plunge grinding and contour grinding; The hollow cylinder is cut by slow wire cutting, and the conical cutting edge is polished to obtain a concave die.

2. The die processing method according to claim 1, characterized in that: Using a CNC lathe, the inner hole and the outer circle with the largest contour of the hollow cylinder are machined, wherein the inner hole is machined with a machining allowance of 4 mm to 6 mm reserved according to the minimum diameter of the cutting edge contour; The maximum outer circle of the contour reserves a machining allowance of 0.5mm~2mm according to the maximum outer circle of the cutting edge contour, and the verticality between the end face of the hollow cylinder and the inner hole is less than or equal to 0.02mm for machining, and ensures that the maximum outer circle of the contour is coaxial with the inner hole.

3. The die processing method according to claim 1, characterized in that: The step of grinding the two end surfaces of the processed hollow cylinder to make the two end surfaces of the hollow cylinder parallel includes: Use a surface grinder to grind the two end surfaces of the hollow cylinder to ensure that the two end surfaces of the hollow cylinder are parallel to 0.009~0.02mm.

4. The die processing method according to claim 1, characterized in that: The outer wall of the hollow cylinder is milled based on the bottom surface of the hollow cylinder after grinding to obtain a conical cutting edge, wherein the conical cutting edge is located on one side of the hollow cylinder, and specifically includes: Taking the polished bottom surface of the hollow cylinder as a reference, a CNC milling machine is used to flatten the outer contour of the hollow cylinder through a one-time clamping and milling process, so that the outer wall of the hollow cylinder has a conical cutting edge.

5. The die processing method according to claim 1, characterized in that: The hollow cylinder after milling is vacuum quenched and cooled, including: A vacuum furnace is used to vacuum quench the hollow cylinder after milling, so that the hardness of the hollow cylinder reaches HRC58-62, and the deformation of the hollow cylinder is less than or equal to 0.02mm; At the same time, the hollow cylinder after vacuum quenching is subjected to ice cooling treatment.

6. The die processing method according to claim 1, characterized in that: The two end surfaces of the hollow cylinder after the ice-cold treatment are finely ground by a surface grinder, specifically comprising: The two end faces of the hollow cylinder are processed by surface grinding to eliminate the deformation caused by quenching so that the surface roughness of the hollow cylinder reaches Ra0.

2.

7. The die processing method according to claim 1, characterized in that: Based on CNC coordinate grinding, the hollow cylinder is processed, including: Install the hollow cylinder on the magnetic table of the CNC coordinate grinder, straighten the process flatness, and align the inner hole of the hollow cylinder.

8. The die processing method according to claim 1, characterized in that: The hollow cylinder after the CNC coordinate grinding is subjected to plunge grinding and contour grinding, specifically comprising: Use CBN grinding wheel to grind the outer wall and conical edge of the hollow cylinder by plunge grinding and contour cutting. In the process of plunge grinding, the bottom surface of the hollow cylinder after flat grinding is used as the reference, and the grinding wheel is plunged up and down along the taper direction of the conical cutting edge, and the feed speed is 3HZ; During the contour cutting process, the grinding wheel cuts along the contour of the conical cutting edge of the hollow cylinder, and feeds clockwise for the outer contour of the hollow cylinder and counterclockwise for the inner contour of the hollow cylinder.

9. The die processing method according to claim 1, characterized in that: The hollow cylinder is cut by wire cutting, and the conical edge is polished to obtain a concave die, which specifically includes: Through multiple slow wire cutting, ensure that the diameter of the inner hole meets the requirements and obtain the concave die.

10. A processing system for a female die of a special blanking die, characterized in that: include: Processing module, used for processing the inner hole and the outer circle with the maximum contour of the hollow cylinder; A grinding module is used to grind the two end surfaces of the hollow cylinder to make the two end surfaces of the hollow cylinder parallel; A milling module, used for milling the outer wall of a hollow cylinder; Quenching module: used for vacuum quenching of hollow cylinders after milling; Cold treatment module, used to cool the hollow cylinder after vacuum quenching; Cutting module, used for cutting hollow cylinders.

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