Clamp tool for rough machining of blade body of small-allowance blade

Abstract

The utility model relates to a clamp tool for rough machining of a blade body of a small-allowance blade. The periphery of a machined part is suspended, cutting-in of a cutter is facilitated, chip removal is convenient, and the tool is designed to reduce deformation of the machined part and meet the size requirement. The machined part is small in deformation, the size is easy to guarantee, the time for clamping and disassembling the part is saved, the efficiency is improved, and the cost is saved.

Description

Technical Field

[0001] This utility model relates to a fixture for machining the blade base and blade back after the blade is clamped in one go and the positioning plate is flipped. In particular, it is a fixture for rough machining of blade body with small margin, which is used for rough machining of small margin blade parts such as aero-engines, and belongs to the field of machine tool fixture components. Background Technology

[0002] The application of three-axis machining centers in rough milling of blade profiles is becoming increasingly widespread in the field of aerospace blade parts processing, especially considering economic efficiency, particularly in the application of tooling on complex curved surfaces and other difficult-to-machine surfaces.

[0003] Most aerospace blades are forged blanks with large allowances. After machining the locating surfaces, rough milling the blade profile is quite difficult. Previously, this was done on ordinary milling machines using template milling or profile milling, which involved extensive use of forming tools. However, the large tool diameter resulted in high resistance, making the blade body prone to deformation and leading to low machining efficiency. Existing surface machining fixtures involve machining the blade head, then removing the part, flipping it, and clamping it on another fixture to machine the blade back. This process, while machining one side, causes deformation or twisting of the blade body due to reduced allowance on that side, resulting in significant deformation and making dimensional control difficult. With continuous technological advancements, the rapid development of artificial intelligence, and the research and manufacturing of advanced equipment, the role of fixtures in blade machining is becoming increasingly important. Direct rough machining on a five-axis blade machining center is costly and inefficient. To save costs, different tooling can be used to achieve different profile cutting when rough machining blades on a three-axis machining center. The main function of the newly designed tooling is to reduce the deformation of the part caused by the tool cutting the surface material of the part during machining when removing the profile allowance. By relying on the clamping force (tension force) of the pressure plate to be greater than the deformation shrinkage force of the part during the initial clamping state, the process table and tenon end face are fixed on the fixture. After machining one side, the part does not need to be disassembled. The base is fixed, and the entire tooling is flipped over and the upper frame is fixed so that the other side can be machined directly. It has the characteristics of convenient clamping, flexibility, accurate positioning, and small deformation of the blade body after machining. It is particularly suitable for batch machining of blades with small allowance. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of large blade deformation after processing by existing tooling, meet product processing quality, reduce production costs and improve efficiency, and provide a fixture tooling with supporting tension and positioning functions, which clamps the processing parts of the parts on the tooling in one go, and processes the blade basin and blade back by the overall flipping positioning frame.

[0005] The technical solution of this utility model is: a fixture for rough machining of blades with small allowance, characterized in that it includes at least: a fixture base assembly 1 (including a baffle 5, a double-ended stud 20, and an internal hexagonal screw 24), a flip plate assembly 2 (including a positioning block 3, a support block 4, a support 6, a positioning pin 7, a pressure plate 8, a pressure plate 9, and a process table positioning block 17). The fixture base assembly 1 includes a boss positioning surface 11 and a boss side positioning surface 12. There are two sets of positioning keyways 10 on the middle boss surface of the boss positioning surface 11, and positioning surfaces 12 and 13 on the side of the boss. It also includes a double-ended stud 20 and a hexagonal flange nut 21. The flip plate assembly 2 includes upper and lower positioning surfaces 14 and 15, a tenon basin side positioning surface 16, a process table positioning block 17, a positioning pin 7, a pressure plate 8, a pressure plate 9, a support 6, and an exhaust edge tenon. The parts are secured by the following components: head-side positioning block 3, intake-side tenon-side support block 4, smooth pressure block 18, four positioning keys 19 in the middle of the flip plate, hexagonal screws 22, 24, 25, 27, and 29, cylindrical pin 28, hexagonal head bolt 23, and process hole 30. The parts are fixed on the process table side of the flip plate 2 using process table positioning block 17, positioning pin 7, pressure plate 8, support 6, and hexagonal head bolt 23. The tenon side is positioned by the tenon basin-side positioning surface 16 on the flip plate 2 and the tenon exhaust-side positioning block 3. The other side is fixed by support block 4, knurled screw 26, and smooth pressure block 18. The back side is fixed by pressure plate 9, support 6, and hexagonal head bolt 23. Finally, the flip plate 2 and the base 1 are positioned by positioning key 19 and baffle 5 and fixed with nut 21, so that the blade area is close to the plane, which is convenient for machining with a three-axis machining center.

[0006] The tooling base assembly 1 consists of a base plate and six bosses. The bottom surface of the boss base plate is parallel to the upper surface 11 of the bosses on the base 1, with a parallelism of no more than 0.01mm. The six bosses are required to be of equal height and have a flatness of no more than 0.01mm. When the tooling is clamped, the bottom surface of the base plate is placed flat on the workbench and the four U-shaped grooves are pressed with screws. The base reference surface 12 is aligned with a 0.02mm difference. Four studs 20 are connected and locked to the bosses. The baffle 5 is connected to the base 1 with screws 24.

[0007] The tenon side of the flip plate assembly 2 is positioned and fixed on the flip plate 2 by the positioning block 3 with two screws 29 (M6×25) and two cylindrical pins 28 (φ6×32). The contact surface of the positioning block 3 is perpendicular to the positioning surface 16 of the tenon side of the flip plate 2, with a perpendicularity of no more than 0.01mm. The longitudinal angle between the positioning block 3 and the positioning surface 14 on the flip plate 2 is guaranteed to be 18°±0.5°. The support block 4 is fixed on the flip plate with two screws 25 (M5×16) and assembled with the knurled screw 26 and the smooth pressure block 18. The support 6 is assembled between the pressure plate 9 and the flip plate 2 to provide support. After assembly, the contact surface of the pressure plate 9 and the positioning surface 16 of the tenon side of the flip plate 2 are required to be parallel to each other.

[0008] The process table side of the flip plate assembly 2 is positioned and fixed by the process table positioning block 17, four hexagon socket screws 27 (M6×25), and two cylindrical pins 28 (φ6×32). The positioning pins 7 are assembled with the process table positioning block 17. After assembly, the lateral angle between the positioning surface of the process table positioning block 17 and the flip plate positioning surface 14 is guaranteed to be 18°±0.5°. The perpendicularity between the pin and the positioning surface is not greater than 0.01mm. Then, the pressure plate 8 is connected with hexagon head bolts 23 (M10×50). The support 6 is assembled between the pressure plate 8 and the flip plate 2 to provide support. The pressing surface of the pressure plate is required to be parallel to the positioning surface of the process table positioning block 17.

[0009] After the flip plate assembly 2 is assembled, the tenon basin side positioning surface 16 and the process table positioning block 17 positioning surface are required to be parallel with a parallelism of no more than 0.01mm, ensuring that the step difference between the two positioning surfaces is 9.8±0.01mm, and the center of the positioning pin 7 and the contact surface between the tenon exhaust side positioning block 3 and the part are guaranteed to be 37.045±0.01mm.

[0010] The rotation plate positioning surfaces 14 and 15 are required to have a parallelism of no more than 0.01 mm and a perpendicularity of no more than 0.015 mm to the side positioning surfaces during processing.

[0011] The base assembly 1, flip plate assembly 2, process table positioning block 17, pressure plate 8, pressure plate 9 and other parts are made of 45 steel and must undergo heat treatment. The heat treatment hardness must not be lower than HRC35. The positioning block 3 and positioning pin 7 are made of CrWMn and the heat treatment hardness must not be lower than HRC55. The roughness of the upper positioning surface 14, lower positioning surface 15 and side surface of the flip plate 2 must reach Ra0.8. The roughness of the upper and lower positioning surfaces of the base 1 must also reach Ra0.8.

[0012] The installation sequence of this fixture is as follows: When loading and unloading parts, open pressure plate 8 and pressure plate 9, clamp the blade basin side downwards, ensure the blade process hole and positioning pin 7 are properly fitted, ensure the blade process basin side positioning surface is flush with the process platform positioning block 17 and check with a 0.02mm feeler gauge, ensure the blade tenon exhaust side reference surface is flush with the process platform 3 positioning surface and check with a 0.02mm feeler gauge, ensure the blade basin side tenon positioning surface is flush with the flip plate basin side positioning surface 16 and check with a 0.02mm feeler gauge, gently tighten pressure plate 8 and pressure plate 9 with bolt 23, and rotate knurled screw 26 to drive the smooth pressure block 18 to the top. After tightening the air intake edge of the blade tenon, tighten bolt 23, and install the flip plate assembly 2 with the parts installed to the base 1. During installation, the process table is on the left side of the machine tool worktable. Place the blade back upwards, and the positioning key 19 and the positioning key groove 10 on the two protrusions in the middle of the base 1 are engaged. The side of the flip plate 2 is close to the baffle 5, and the positioning surface 15 of the flip plate 2 is close to the six protrusions of the base 1. Use a 0.02mm feeler gauge to check the gap at the above-mentioned mating surfaces. After confirming that the above gaps meet the requirements, tighten the nut 21. When machining the blade basin side, flip the flip frame 2 back and forth and repeat the installation and inspection process with the base 1.

[0013] The advantages of this utility model are: The suspended position around the workpiece facilitates tool entry and chip removal. The purpose of this fixture is to reduce deformation after machining and meet dimensional requirements. It mainly utilizes the fact that the clamping force (friction) of the tenon and upper and lower positioning surfaces of the blade on the flip plate 2 assembly (pressure plates 8 and 9) in its natural state is greater than the internal stress generated when the tool removes the workpiece blank during blade machining. The workpiece is clamped in one go without disassembly. Because the blade is a forged blank, the black outer layer bears a large internal stress. After removing the black outer layer from one side, deformation tends to occur on the machined surface, while the unmachined surface will also deform. The deformation generated during blade basin machining will not result in irreversible deformation due to the need for disassembly during blade back machining. The workpiece is machined after one flip of the flip plate 2 assembly. This results in minimal deformation of the machined part, easy dimensional assurance, and saves time on clamping and disassembly, improving efficiency and saving costs.

[0014] The present invention will be further described below with reference to the accompanying drawings of the embodiments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the tooling structure of this utility model;

[0016] Figure 2 Schematic diagram of the flip panel assembly structure;

[0017] Figure 3 Schematic diagram of the base component structure;

[0018] Figure 4 Schematic diagram of blade clamping status;

[0019] Figure 5 This is a schematic diagram of the tooling structure before it is flipped over;

[0020] Figure 6 This is a schematic diagram of the structure after the tooling is flipped over.

[0021] In the diagram, 1. Base assembly; 2. Flip plate assembly; 3. Positioning block; 4. Support block; 5. Baffle; 6. Support; 7. Positioning pin; 8. Pressure plate; 9. Pressure plate; 10. Positioning keyway; 11. Boss positioning surface; 12. Positioning surface on one side of the boss; 13. Positioning surface on the other side of the boss; 14. Upper positioning surface of the flip frame; 15. Lower positioning surface of the flip frame; 16. Positioning surface of the flip frame tenon on the side; 17. Process table positioning block; 18. Smooth pressure block; 9. Locating key; 20. Double-ended stud M10×85; 21. Hexagonal flange nut M10; 22. Socket head cap screw M6×16; 23. Hex head bolt M10×50; 24. Socket head cap screw M5×16; 25. Socket head cap screw M5×16; 26. Knurled screw M8×35; 27. Socket head cap screw M6×25; 28. Cylindrical pin φ6×25; 29. ​​Socket head cap screw M6×25; 30. Process hole. Detailed Implementation

[0022] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6As shown, a fixture for rough machining of blades with small allowance includes: a fixture base assembly 1 (including a baffle 5, a double-ended stud 20, and an internal hexagonal screw 24), and a flip plate assembly 2 (including a positioning block 3, a support block 4, a support 6, a positioning pin 7, a pressure plate 8, a pressure plate 9, and a process table positioning block 17). The fixture base assembly 1 includes a boss positioning surface 11 and a boss side positioning surface 12. Two sets of positioning keyways 10 are located on the middle boss surface of the boss positioning surface 11, and positioning surfaces 12 and 13 are located on the side of the boss. It also includes a double-ended stud 20 and a hexagonal flange nut 21. The flip plate assembly 2 includes upper and lower positioning surfaces 14 and 15, a tenon-side positioning surface 16, a process table positioning block 17, a positioning pin 7, a pressure plate 8, a pressure plate 9, a support 6, an exhaust side tenon-side positioning block 3, and an inlet... The components include a tenon side support block 4, a smooth pressure block 18, four positioning keys 19 in the middle of the flip plate, hexagonal screws 22, 24, 25, 27, and 29, cylindrical pins 28, hexagonal head bolts 23, and process holes 30. The parts are fixed on the process table side of the flip plate 2 using process table positioning blocks 17, positioning pins 7, pressure plates 8, supports 6, and hexagonal head bolts 23. The tenon side is positioned using the tenon basin side positioning surface 16 on the flip plate 2 and the tenon exhaust side using positioning blocks 3. The other side is fixed using support blocks 4, knurled screws 26, and smooth pressure blocks 18. The back side is fixed using pressure plates 9, supports 6, and hexagonal head bolts 23. Finally, the flip plate 2 and the base 1 are positioned using positioning keys 19 and baffles 5 and fixed with nuts 21, so that the blade shape is close to the plane, making it easy to process with a three-axis machining center.

[0023] The tooling base assembly 1 consists of a base plate and six bosses. The bottom surface of the boss base plate is parallel to the upper surface 11 of the bosses on the base 1, with a parallelism of no more than 0.01mm. The six bosses are required to be of equal height and have a flatness of no more than 0.01mm. When the tooling is clamped, the bottom surface of the base plate is placed flat on the workbench and the four U-shaped grooves are pressed with screws. The base reference surface 12 is aligned with a 0.02mm difference. Four studs 20 are connected and locked to the bosses. The baffle 5 is connected to the base 1 with screws 24.

[0024] like Figure 2 As shown, the tenon side of the flip plate assembly 2 is positioned and fixed on the flip plate 2 by the positioning block 3 using two screws 29 (M6×25) and two cylindrical pins 28 (φ6×32). The contact surface of the positioning block 3 is perpendicular to the positioning surface 16 of the tenon side of the flip plate 2, with a perpendicularity of no more than 0.01mm. The longitudinal angle between the positioning block 3 and the positioning surface 14 on the flip plate 2 is guaranteed to be 18°±0.5°. The support block 4 is fixed on the flip plate with two screws 25 (M5×16) and assembled with the knurled screw 26 and the smooth pressure block 18. The support 6 is assembled between the pressure plate 9 and the flip plate 2 to provide support. After assembly, the contact surface of the pressure plate 9 and the positioning surface 16 of the tenon side of the flip plate 2 are required to be parallel to each other.

[0025] The process table side of the flip plate assembly 2 is positioned and fixed by the process table positioning block 17, four hexagon socket screws 27 (M6×25), and two cylindrical pins 28 (φ6×32). The positioning pins 7 are assembled with the process table positioning block 17. After assembly, the lateral angle between the positioning surface of the process table positioning block 17 and the flip plate positioning surface 14 is guaranteed to be 18°±0.5°. The perpendicularity between the pin and the positioning surface is not greater than 0.01mm. Then, the pressure plate 8 is connected with hexagon head bolts 23 (M10×50). The support 6 is assembled between the pressure plate 8 and the flip plate 2 to provide support. The pressing surface of the pressure plate is required to be parallel to the positioning surface of the process table positioning block 17.

[0026] After the flip plate assembly 2 is assembled, the tenon basin side positioning surface 16 and the process table positioning block 17 positioning surface are required to be parallel with a parallelism of no more than 0.01mm, ensuring that the step difference between the two positioning surfaces is 9.8±0.01mm, and the center of the positioning pin 7 and the contact surface between the tenon exhaust side positioning block 3 and the part are guaranteed to be 37.045±0.01mm.

[0027] The rotation plate positioning surfaces 14 and 15 are required to have a parallelism of no more than 0.01 mm and a perpendicularity of no more than 0.015 mm to the side positioning surfaces during processing.

[0028] like Figure 3 As shown, the base assembly 1, flip plate assembly 2, process table positioning block 17, pressure plate 8, pressure plate 9 and other parts are made of 45 steel and all need to undergo heat treatment. The heat treatment hardness cannot be lower than HRC35. The positioning block 3 and positioning pin 7 are made of CrWMn and the heat treatment hardness cannot be lower than HRC55. The roughness of the upper positioning surface 14, lower positioning surface 15 and side surface of the flip plate 2 reaches Ra0.8. The roughness of the upper and lower positioning surfaces of the base 1 also needs to reach Ra0.8.

[0029] like Figure 4 , Figure 5 , Figure 6As shown, the installation sequence of this fixture is as follows: When loading and unloading parts, open pressure plate 8 and pressure plate 9, clamp the blade basin side downwards, ensure the blade process hole and positioning pin 7 are properly fitted, ensure the blade process basin side positioning surface is flush with the process platform positioning block 17 and check with a 0.02mm feeler gauge, ensure the blade tenon exhaust side reference surface is flush with the process platform 3 positioning surface and check with a 0.02mm feeler gauge, ensure the blade basin side tenon positioning surface is flush with the flip plate basin side positioning surface 16 and check with a 0.02mm feeler gauge, gently tighten pressure plate 8 and pressure plate 9 with bolt 23, and rotate knurled screw 26 to drive smooth pressure block 1. 8. After tightening the air intake edge of the blade tenon, tighten bolt 23 and install the flip plate assembly 2 with the parts installed to the base 1. During installation, the process table is on the left side of the machine tool worktable. Place the blade back upwards. The positioning key 19 and the positioning key groove 10 on the two protrusions in the middle of the base 1 are engaged. The side of the flip plate 2 is close to the baffle 5. The positioning surface 15 of the flip plate 2 is close to the six protrusions of the base 1. Use a 0.02mm feeler gauge to check the gap at the above-mentioned mating surfaces. After confirming that the above gaps meet the requirements, tighten the nut 21. When machining the blade basin side, flip the flip frame 2 back and forth and repeat the installation and inspection process with the base 1.

Claims

1. A fixture for rough machining of blades with small allowance, characterized in that: at least include: The fixture base assembly and the flip plate assembly are as follows: The fixture base assembly includes a baffle, double-ended studs, hex socket screws, a boss positioning surface and a boss side positioning surface; the flip plate assembly includes a positioning block, a support block, a support, a positioning pin, a pressure plate, and a process table positioning block. The boss positioning surface has two sets of positioning keyways on the middle boss surface, and positioning surfaces and positioning surfaces on the sides of the boss. It also includes double-ended studs and hex flange nuts. The flip plate assembly includes upper and lower positioning surfaces, a tenon-side positioning surface, a process table positioning block, a positioning pin, a pressure plate, a support, an exhaust side tenon-side positioning block, an intake side tenon-side support block, and a smooth pressure block. The flip plate is equipped with a positioning key, hexagonal screws, cylindrical pins, hexagonal head bolts, and process holes in the middle. The parts are fixed on the process table side of the flip plate using process table positioning blocks, positioning pins, pressure plates, supports, and hexagonal head bolts. The tenon side is positioned using the tenon basin side positioning surface and the tenon venting side side of the flip plate, and the other side is fixed using support blocks, knurled screws, and smooth pressure blocks. The back side is fixed using pressure plates, supports, and hexagonal head bolts. Finally, the flip plate and the base are positioned using positioning keys and baffles and fixed with nuts, so that the blade shape is close to the plane, which is convenient for machining with a three-axis machining center.

2. The fixture for rough machining of blades with small allowance as described in claim 1, characterized in that: The tooling base assembly includes a boss base plate and six bosses. The bottom surface of the boss base plate is parallel to the upper surface of the bosses on the base, with a parallelism of no more than 0.01mm. The six bosses are required to be of equal height, with a flatness of no more than 0.01mm. When clamping the tooling, the bottom surface of the base plate is placed flat on the workbench and the four U-shaped grooves are pressed with screws. The base reference surface is aligned with no more than 0.02mm. Four studs are connected and locked to the bosses. The baffle is connected to the base with screws.

3. The fixture for rough machining of blades with small allowance as described in claim 1, characterized in that: The tenon side of the flip plate assembly is fixed on the flip plate by a positioning block with two screws and two cylindrical pins. The contact surface of the positioning block is perpendicular to the positioning surface of the tenon side of the flip plate, with a perpendicularity of no more than 0.01mm. The longitudinal angle between the positioning block and the positioning surface on the flip plate is guaranteed to be 18°±0.5°. The support block is fixed on the flip plate with two screws and assembled with knurled screws and smooth pressure blocks. It is assembled between the pressure plate and the flip plate to provide support. After assembly, the contact surface of the pressure plate and the positioning surface of the tenon side of the flip plate are required to be parallel to each other.

4. The fixture for rough machining of blades with small allowance as described in claim 1, characterized in that: The flip plate assembly is fixed to the process table side by a process table positioning block, four hexagon socket screws, and two cylindrical pins. The positioning pins are assembled with the process table positioning block. After assembly, the lateral angle between the positioning surface of the process table positioning block and the positioning surface of the flip plate is guaranteed to be 18°±0.5°. The perpendicularity of the pins to the positioning surface is no more than 0.01mm. Then, the pressure plate is connected and supported between the pressure plate and the flip plate with hexagon head bolts to provide support. The pressing surface of the pressure plate and the positioning surface of the process table positioning block are required to be parallel.

5. The fixture for rough machining of blades with small allowance as described in claim 1, characterized in that: The tenon basin-side positioning surface of the flip plate assembly is kept parallel to the positioning surface of the process table positioning block, with a parallelism of no more than 0.01mm, ensuring that the step difference between the two positioning surfaces is 9.8±0.01mm, and the contact surface between the positioning pin center and the tenon exhaust side positioning block and the part is guaranteed to be 37.045±0.01mm.

6. The fixture for rough machining of blades with small allowance as described in claim 1, characterized in that: The aforementioned flip plate positioning surface and positioning surface are required to have a parallelism of no more than 0.01mm and a perpendicularity of no more than 0.015mm to the side positioning surface during processing.

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