Processing Method for Weak Rigidity and Large Arc Castings

Abstract

The processing method of a weakly rigid large arc-shaped casting belongs to the field of machining. According to the structural form of the weakly rigid large arc-shaped casting and the parts to be machined by cutting, in addition to designing supports and clamping at the regular planar-shaped process lugs, it is necessary to set up self-adaptive supports and self-adaptive clamping at the internal closed areas and the distal sharp corners of the weakly rigid large arc-shaped casting. The support and clamping structures should be set both inside and outside the ribbed parts of the weakly rigid large arc-shaped casting, and the support points should be evenly distributed; the support structure in the internal closed area is a spherical support structure; after installing and positioning the weakly rigid large arc-shaped casting through the support and clamping structures, workpiece machining is carried out.

Description

Technical Field

[0001] The present invention relates to a design method of machining process equipment, and particularly to the surface milling of large arc-shaped castings of aviation products with a closed structure. Background Art

[0002] The aircraft cockpit structural parts adopt an integral closed precision casting structure, and its rib parts do not need to be machined. However, for key assembly coordination parts, such as joint surfaces, airtight belt grooves, and sealing groove structural parts, precision milling is carried out. The general characteristics of the product structure are a large arc segment integral closed structure with a middle honeycomb structure. Between the machining parts, such as Figure 1 , the overall structure rigidity of the product shows the characteristics of being weak at the periphery and strong in the middle. The placement state of the product during machining is shown in Figure 2 , the set pressing and supporting parts are arranged around the milling arc segment, and the supporting and pressing structures are all arranged near the machining parts of the product. Because its interior is sealed inside by the surrounding supporting and pressing structures, it is impossible to manually operate and adjust the support inside the product structure, and it is impossible to set the pressing structure at the non-supporting parts. When machining the periphery of the arc segment, machining tremors occur, affecting the machining quality of the product. Surface quality problems such as ripples and machining out-of-tolerance often occur during the machining process. To reduce tremors and machining out-of-tolerance problems, in addition to improving tool parameters and cutting parameters, the workshop technicians cannot effectively solve the problem of large machining vibrations. Through in-depth analysis, it is considered that the insufficient rigidity of the clamping system is also one of the main reasons. By increasing the number of pressing points near the milling machining parts, due to inappropriate addition of pressing points, it is impossible to effectively improve the overall rigidity of the product and the tooling after clamping. Finally, the above problems can only be solved by reducing the machining cutting parameters, which greatly reduces the production efficiency of the product. Summary of the Invention

[0003] Technical problems to be solved: The method of the present invention mainly provides a technical method that can stably support and press the inside and curved surface parts of the arc-shaped curved surface parts, so as to form a stable rigid structure body after the product and the tooling are clamped, and solve the machining tremor problem during the machining process at the source of vibration.

[0004] Technical solution of the present invention:

[0005] A machining method for large arc-shaped castings with weak rigidity is as follows:

[0006] According to the structural form of the large arc-shaped casting with weak rigidity and the parts to be machined by cutting, in addition to designing supports and clamping at the regular planar process lugs, it is necessary to set up adaptive supports and adaptive clamping at the internal closed areas and distal sharp corners of the large arc-shaped casting with weak rigidity. The support and clamping structures should be set inside and outside the ribbed parts of the large arc-shaped casting with weak rigidity, and the support points should be evenly distributed; the support structure in the internal closed area is a spherical support structure; after installing and positioning the large arc-shaped casting with weak rigidity through the support and clamping structures, the workpiece is machined.

[0007] Furthermore, the spherical support structure uses spring force adaptive support in combination with hydraulic locking and pneumatic locking, or uses a pneumatically driven, hydraulically driven, or electrically driven spherical support structure with a sensor structure.

[0008] Furthermore, the spherical support structure supports the arc surface of the large arc-shaped casting with weak rigidity with a force of 5N through the springs of multiple elastic self-locking devices.

[0009] Furthermore, the large arc-shaped casting with weak rigidity has a triangular arc segment structure form. One end of the arc segment is a tip, and the other two ends are in a handlebar-shaped protrusion. According to the processing process requirements of the large arc-shaped casting with weak rigidity, the overall structural composition of the large arc-shaped casting with weak rigidity during processing is simulated and analyzed, and the rigidly weak and vibration-prone parts where the cutting force is transmitted are found. The large arc-shaped casting with weak rigidity is divided into main support structures set at the outer boundary of the arc-shaped part, the middle process lugs, the two handlebar-shaped protrusion parts, and the arc segment tip part.

[0010] Furthermore, the placement state requirement of the large arc-shaped casting with weak rigidity is: place the two handlebar-shaped protrusion parts of the large arc-shaped casting with weak rigidity in a horizontal state above, the tip below, and the convex surface of the arc segment product facing down.

[0011] According to the structural dimensions of the large arc-shaped casting with weak rigidity, at the handle protrusion parts where the structure of the large arc-shaped casting with weak rigidity is weak, an upper and lower split support structure is designed. The upper and lower split support structure is integrally fixed on the bottom plate 27;

[0012] Two support and clamping structures are connected and installed on the lower support 2 of the upper and lower split support structure. One is a fixed support structure, and the other is a movable support structure. The fixed support structure includes an upper support 1, a pressing plate 3, a nut 4, a stud 5, and a support bolt 6. The movable support structure includes a pressing plate 3, a nut 4, a stud 5, a support bolt 6, and a movable support 7; the movable support structure can be adjusted to adapt to the actual support parts of the blank product;

[0013] The upper support 1 is fixed on the lower support 2. An oblong hole is formed in the pressure plate 3 for adjusting the pressing position. The stud 5 passes through the oblong hole and its lower end is screwed into the upper support 1 to achieve fixation with the upper support 1. A nut 4 is screwed onto the upper end. The pressure plate 3 is pressed by rotating the nut 4. The support bolt 6 passes through the pressure plate 3 and is threadedly connected with the pressure plate 3. Its lower end contacts the upper surface of the upper support 1. The height of the pressure plate 3 relative to the upper support 1 is adjusted by the support bolt 6 through the thread.,

[0014] The movable support 7 can slide relative to the lower support 2. The upper end of the T-slot nut 9 is connected with the socket head cap screw 8 passing through the movable support 7 to form a sliding support assembly. A sliding pair structure is formed between the T-slot nut 9 and the T-slot structure made on the lower support 2. A round hole is formed in the pressure plate 3 of the movable support structure. The stud 5 passes through the round hole and its lower end is screwed into the movable support 7 to achieve fixation with the movable support 7. A nut 4 is screwed onto the upper end. The pressure plate 3 is pressed by rotating the nut 4. The support bolt 6 passes through the pressure plate 3 and is threadedly connected with the pressure plate 3. Its lower end contacts the upper surface of the lower support 2. The height of the pressure plate 3 relative to the lower support 2 is adjusted by the support bolt 6 through the thread; after the movable support 7 is adjusted to an appropriate position, it will be fixed on the lower support 2; after the movable support 7 is adjusted to an appropriate position, it will be fixed on the lower support 2.

[0015] The support and pressing structure at the tip includes a profiling pressing plate assembly and an adjustable support structure; the profiling pressing plate assembly includes a profiling pressing plate 25, a stud 5, a nut 4, and a support bolt 6. The pressing surface of the profiling pressing plate 25 is cut according to the product profile. The profiling pressing plate 25 has a limiting and pressing function. A long circular hole is opened on the profiling pressing plate 25. The stud 5 passes through the long circular hole and is screwed into the bottom plate 27 at the lower end to achieve fixation with the bottom plate 27. The nut 4 is screwed onto the upper end, and the profiling pressing plate 25 is pressed by rotating the nut 4. The support bolt 6 passes through the profiling pressing plate 25 and is threadedly connected to the profiling pressing plate 25. The lower end is placed in the tapered hole opened on the bottom plate 27. The support bolt 6 adjusts the height of the profiling pressing plate 25 relative to the lower bottom plate 27 through threads; there are two groups of adjustable support structures, distributed on both sides of the profiling pressing plate assembly; each group includes a fixed support 30, a removable pressing plate 26, a stud 5, a nut 4, a support bolt 6, an adjustable support 28, an external hexagonal thin nut 29, and a fixed support 30. The two fixed supports 30 are fixed on the bottom plate 27 and are used to support and position the left and right two lugs at the tip of the weakly rigid large-arc-shaped casting. A removable pressing plate 26 is arranged above the fixed support 30. A long circular hole is opened on the removable pressing plate 26 for adjusting the pressing position. The stud 5 passes through the long circular hole and is screwed into the base 27 at the lower end to achieve fixation with the removable pressing plate 26. The nut 4 is screwed onto the upper end, and the removable pressing plate 26 is pressed by rotating the nut 4. The support bolt 6 passes through the removable pressing plate 26 and is threadedly connected to the removable pressing plate 26, and contacts the upper surface of the bottom plate 27. The support bolt 6 adjusts the height of the removable pressing plate 26 relative to the lower bottom plate 27 through threads; the adjustable support 28 is located below the profiling pressing plate 25. The shape of the contact part with the weakly rigid large-arc-shaped casting is spherical, and the corresponding contact part is point contact. It is threadedly connected to the bottom plate 27 to achieve height adjustment, and thus support for the weakly rigid large-arc-shaped casting is realized. The external hexagonal thin nut 29 is sleeved on the adjustable support 28 and is threadedly connected to the adjustable support 28 for tightening the adjustable support 28.

[0016] Furthermore, the auxiliary support structure includes three support seats, namely the large support seat 14 in the middle and the small support seats 17 on both sides thereof. The shape of the support surface of the support seat is parallel to the arc tangent of the arc-shaped product and is at a certain distance therefrom, and it is ensured that the distance is controlled within a certain range. There are two small support seats 17 in total, and the support surface is composed of a section of tangent line and is arranged on both sides. The basic support surface of the large support seat 14 is composed of multiple lines parallel to the arc tangent of the arc-shaped product. Hydraulic zero-force support cylinders 15 are arranged on the support surfaces of the small support seats 17 and the large support seat 14 at certain positions, ensuring that when the fulcrum of the hydraulic zero-force support cylinder 15 is in contact with the theoretical outer shape height of the product data after installation, the length of its hydraulic rod can extend or retract by no less than 7 mm. This dimension should be greater than the maximum deviation dimension of the product blank. In the free state, the spring support force of the hydraulic zero-force support cylinder is less than 0.5 kg per piece. Hydraulic passage holes are designed inside the structures of the small support seats 17 and the large support seat 14, and connecting threads are made at the ends of the holes. The hydraulic zero-force support cylinders 15, the accumulator assembly 20, and the hydraulic pump assembly 21 are connected together using two-way connectors 19, conduits 16, and four-way connectors 18 to form a micro-elastic force support contact and locking control loop.

[0017] The fork-shaped hinge support assembly 22 is fixedly connected to the bottom plate 27 through screws and pin connectors. The bottom end of the longitudinal pressing plate assembly 24 is rotatably connected to the fork-shaped hinge support assembly 22. The top end of the longitudinal pressing plate assembly 24 is located between two vertically parallel pressing plates at the top of the large support seat 14 during use and is fixedly connected by contact extrusion with screws and nuts. A pressing plate 3 is arranged below the two vertically parallel pressing plates at the top of the large support seat 14. Long circular holes are opened on the pressing plate 3 for adjusting the pressing position. The pressing bolt 13 passes through the long circular hole and is screwed into the large support seat 14 at the lower end to achieve fixation with the large support seat 14, and a nut 4 is screwed onto the upper end. The pressing plate 3 is pressed by rotating the nut 4. The support bolt 6 passes through the pressing plate 3 and is threadedly connected with the pressing plate 3. The lower end contacts the upper surface of the large support seat 14. The support bolt 6 adjusts the height of the pressing plate 3 relative to the large support seat 14 through the thread.

[0018] Preferably, the upper support 1 is connected to the lower support 2 through internal hexagonal connection screws 8 and cylindrical fixing pins 10.

[0019] Preferably, a transverse pressing plate assembly 23 capable of swinging the pressing plate is designed on the longitudinal pressing plate assembly 24. A spherical movable joint perpendicular to each other is designed at the connection part between the longitudinal pressing plate assembly 24 and the transverse pressing plate assembly 23, enabling adaptive two-way adaptive floating pressing when pressing the product rib, ensuring the reliability of the pressing contact.

[0020] Preferably, a lifting point 31 is arranged on the bottom plate 27.

[0021] Preferably, counterbore holes are arranged on the upper surface of the large support seat 14, and weak-rigidity large arc-shaped castings are positioned by cooperating with positioning pins 11 and positioning bushings 12.

[0022] Advantages of the present invention:

[0023] 1. The adjustable mechanism has been verified to have good use effects, can achieve accurate auxiliary replacement for auxiliary support positioning, can achieve rapid and accurate auxiliary support, effectively reduce the on-site adjustment difficulty, reduce the working intensity of workers' operation and adjustment, and has reliable and stable positioning during use, ultimately ensuring the final accuracy of the processed products.

[0024] 2. This technical method completely solves the problem of chatter in the milling process of large arc castings, ensures reliable clamping on the basis of improving the cutting efficiency of the machine tool, and relatively improves the product processing quality and processing efficiency by at least 50% compared with the previous stage. Description of the drawings

[0025] Figure 1 The three lines with thickened endpoints are the parts of the surface support points;

[0026] Figure 2 The hatched part is the analysis of the support parts of the products distributed in the support area;

[0027] Figure 3 Product state diagram under view point one;

[0028] Figure 4 Product state diagram under view point two;

[0029] Figure 5 Schematic diagram of the product processing part (the blackened part);

[0030] Figure 6 State after installing the product;

[0031] Figure 7 State before installing the product;

[0032] In the figure: 1. Upper support; 2. Lower support; 3. Pressure plate; 4. Nut; 5. Stud; 6. Support bolt; 7. Movable support; 8. Socket head cap screw for connection; 9. T-slot nut; 10. Cylindrical fixing pin; 11. Positioning pin; 12. Positioning bushing; 13. Clamping bolt; 14. Large support; 15. Hydraulic zero-force support cylinder; 16. Pipe; 17. Small support; 18. Four-way joint; 19. Two-way joint; 20. Accumulator assembly; 21. Hydraulic pump assembly; 22. Fork-shaped hinge support assembly; 23. Transverse rotating pressure plate; 24. Longitudinal rotating pressure plate; 25. Contour pressure plate; 26. Removable pressure plate; 27. Base plate; 28. Adjustable support; 29. Thin hexagon nut; 30. Fixed support; 31. Lifting point. Detailed implementation manners

[0033] According to the product structure form and the parts to be machined by cutting, in addition to designing supports and clamps at the regular planar process lugs, adaptive supports and adaptive clamps need to be set at the internal closed areas and the distal sharp corners of the product. The support and clamp structures should be set inside and outside the ribbed parts of the product to facilitate structural design and increase the outer wall Figure 1 Design spherical zero-force support points in the area shown. The support points should be evenly distributed and evenly set in the inner closed area near the cutting part. Preferably, one support point is set every 200 mm - 260 mm. The required structure should be able to avoid the participation of workers, improve the support efficiency, and automatically adjust the support for the internal closed area that cannot be reached manually. The support structure for the internal closed area is a spherical support structure; preferably, a spring force adaptive support is used in combination with hydraulic locking, pneumatic locking, or a pneumatically driven, hydraulically driven, or electrically driven spherical support structure with a sensor structure.

[0034] The support structure for the internal closed area uses a spring force adaptive support for the product. After the product is installed and positioned, the spherical support structure contacts the product surface under the action of spring force, pneumatic drive, hydraulic drive, or electric drive. The supporting force of the spring force is such that it can reliably contact the product but is only a contact force and cannot be too large to prevent the product from deforming. At this time, the supporting force should be along the normal direction of the product surface. According to the processing and placement posture of the product, analyze the direction of the supporting force. The sum of the vertical components of the contact forces generated at the contact points should be avoided from being greater than the product gravity. After lifting the positioned product, a positioning error is generated between the product and the target machining position, that is: when ∑N 支撑力垂直分力 <W 产品 When this occurs, the entire support structure achieves self-locking and feeds back a signal to achieve self-locking of the hydraulic support or electric support structure, ensuring that the self-locking force of each support during clamping is greater than the clamping force generated when the opposite clamping structure clamps. That is: N 支撑力 >P 压紧力 The clamping structure also needs to be connected to the tooling when not working to prevent loss. The clamping part is set at the ribbed part. The pressure points between the longitudinal pressing plate and the product can swing freely to ensure reliable fitting between the pressure points and the product parts during clamping. The longitudinal clamping structure is designed as a flip card type adaptive floating clamping structure to ensure the convenience of using the clamping mechanism. Due to the above-mentioned support and clamping technical solutions, reliable support and clamping are achieved.

[0035] Set a product adaptive adjustable auxiliary support device in a specific area on the inner side of the arc section of the clamped product. The surface of the arc section product is supported by the springs of multiple elastic self-locking devices with a force of about 5 N, and the auxiliary support points with controllable supporting force; only set the clamping points at the end edges of the product arc section. Through the multi-support points with reliable contact, the overall structural rigidity of the tooling and the product after clamping is effectively improved. Through actual application, the cutting tremor during the processing is effectively eliminated, and the problems such as surface processing ripples caused by insufficient rigidity during the processing of large arc-shaped casting products are completely solved.

[0036] The structure of the large-arc-shaped casting is in the form of a triangular arc segment structure. One end of the arc segment is a tip, and the other two ends are in the shape of handlebar protrusions. According to the processing requirements of the large-arc-shaped casting, the overall structure composition of the large-arc-shaped casting during processing is simulated and analyzed, and the rigidly weak and vibration-prone parts where the cutting force is transmitted are found. The product is divided into a main support structure set at the outer boundary of the arc-shaped part, the middle process earpiece, the two handlebar protrusion parts, and the tip part of the arc segment. An auxiliary support area for improving the rigidity of the entire arc-shaped part is set, such as Figure 1 , from the tip of the arc-shaped part to the middle support process earpiece is the arc segment mid-division area belt. A total of 3 areas, including this area belt and the approximately mid-division part area belt of the other two arc-shaped handle belts of the casting, are pre-set as auxiliary support areas, effectively increasing the overall rigidity of the arc-shaped casting during processing.

[0037] The requirements for the processing and placement state of the product, such as Figure 1 , it is necessary to place the two handlebar protrusion parts of the product in a horizontal state above, the tip below, and the convex surface of the arc segment product facing down.

[0038] Remove all the pressure plates, and rotate the transverse rotating pressure plate 23 around the hinge pin on the fork-shaped hinge support and rotate the longitudinal rotating pressure plate 24 out of the pressing area.

[0039] Control the pressure relief through the hydraulic pump assembly 21. The hydraulic zero-force support cylinder 15 pushes the support piston out to the maximum stroke through the spring set inside the cylinder body. At this time, the height of the support point is controlled slightly higher than the contact state with the product blank surface. Install the product on the fixture. At this time, the weight of the product is sufficient to overcome the sum of the support forces of all the hydraulic zero-force support cylinders 15. The support piston fulcrum of the hydraulic zero-force support cylinder 15 is in reliable contact with the surface of the product blank. Use the above-mentioned pressure plates to press the product. After the hydraulic pump reaches the rated pressure value, disconnect the connection between the hydraulic pump assembly 21 and the accumulator assembly 20. The accumulator assembly 20 replenishes oil into the circuit at any time to ensure that the rated pressure in the circuit remains unchanged during operation. The hydraulic pressure locks the hydraulic zero-force support cylinder 15 to ensure that it does not retract after being pressed. At this time, the auxiliary support hydraulic zero-force support cylinder 15 and each main support surface of the product blank reliably support the product, the pressure plates press the product, forming a reliable rigid whole with the product, effectively preventing the machining tremor caused by the product being suspended during cutting, and improving the machining quality and efficiency of the product.

[0040] Such as Figure 2 In the left side view, hoist the product on the fixture with its arc tip down. Adjust the adjustable support 28. When the gap between the upper handle of the product and the positioning surfaces of the upper support and the movable support 7 on part 1 is zero, the adjustment is completed. Insert the positioning pin 11, and the installation and adjustment of the product are completed.

[0041] Press the product tightly at the corresponding positions with the pressing plate 2, the profiling pressing plate 25, the removable pressing plate 26, and the matching pressing bolts or nuts, etc. Rotate the transverse rotating pressing plate 23 and cooperate with the longitudinal rotating pressing plate 24 to adaptively buckle on the flat ribs of the product to complete the pressing.

Claims

1. Processing method for a weakly rigid large-arc-shaped casting, characterized in that, The details are as follows: The weakly rigid large arc-shaped casting has a triangular arc segment structure. One end of the arc segment is a tip, and the other end has two handle-shaped protrusions. Place the two handle-shaped protrusion parts of the weakly rigid large arc-shaped casting horizontally above, with the tip below and the convex side of the arc segment facing downwards. According to the processing technology requirements of the weakly rigid large arc-shaped casting, simulate and analyze the overall structural composition of the weakly rigid large arc-shaped casting during processing, and find the parts with weak rigidity and prone to vibration where the cutting force is transmitted. In addition to designing supports and clamps at the regular planar process lugs, support and clamp structures need to be set in the internal closed area and the tip of the weakly rigid large arc-shaped casting. The support and clamp structures should be set inside and outside the ribbed parts of the weakly rigid large arc-shaped casting, and the support points should be evenly distributed. The support structure in the internal closed area is a spherical support structure. After installing and positioning the weakly rigid large arc-shaped casting through the support and clamp structures, the workpiece is processed; According to the structural dimensions of the weakly rigid large arc-shaped casting, an upper and lower split support structure is designed at the handle-shaped protrusion part with weak structural rigidity of the weakly rigid large arc-shaped casting. The upper and lower split support structure is fixedly installed on the bottom plate (27). Two support and clamp structures are connected and installed on the lower support (2) of the upper and lower split support structure, one is a fixed support structure and the other is a movable support structure. The movable support structure can be adjusted to adapt to the actual support parts of the blank product; The support and clamp structure at the tip part includes a profiling pressing plate assembly and an adjustable support structure; The profiling pressing plate assembly includes a profiling pressing plate (25), studs (5), nuts (4), and support bolts (6). The pressing surface of the profiling pressing plate (25) is cut according to the profile of the weak-rigidity large-arc-shaped casting. The profiling pressing plate (25) has a limiting and pressing function. A long circular hole is provided on the profiling pressing plate (25). The stud (5) passes through the long circular hole, and the lower end is screwed into the bottom plate (27) to fix it to the bottom plate (27). The nut (4) is screwed onto the upper end, and the profiling pressing plate (25) is pressed by rotating the nut (4). The support bolt (6) passes through the profiling pressing plate (25) and is threadedly connected to the profiling pressing plate (25). The lower end is placed in the tapered hole provided on the bottom plate (27). The support bolt (6) adjusts the height of the profiling pressing plate (25) relative to the lower bottom plate (27) through threads; there are two groups of adjustable support structures, distributed on both sides of the profiling pressing plate assembly; each group includes a fixed support (30), a removable pressing plate (26), studs (5), nuts (4), support bolts (6), an adjustable support (28), a thin hexagon nut (29), and a fixed support (30). The two fixed supports (30) are fixed to the bottom plate (27) to support and position the two lugs on the left and right of the tip of the weak-rigidity large-arc-shaped casting. A removable pressing plate (26) is arranged above the fixed support (30). A long circular hole is provided on the removable pressing plate (26) to adjust the pressing position. The stud (5) passes through the long circular hole, and the lower end is screwed into the bottom plate (27) to fix it to the removable pressing plate (26). The nut (4) is screwed onto the upper end, and the removable pressing plate (26) is pressed by rotating the nut (4). The support bolt (6) passes through the removable pressing plate (26) and is threadedly connected to the removable pressing plate (26), and contacts the upper surface of the bottom plate (27). The support bolt (6) adjusts the height of the removable pressing plate (26) relative to the lower bottom plate (27) through threads; the adjustable support (28) is located below the profiling pressing plate (25). The shape of the contact part with the weak-rigidity large-arc-shaped casting is spherical, and the corresponding contact part is point contact. It is threadedly connected to the bottom plate (27) to achieve height adjustment, thereby realizing the support for the weak-rigidity large-arc-shaped casting. The thin hexagon nut (29) is sleeved on the adjustable support (28) and is threadedly connected to the adjustable support (28) to lock the adjustable support (28); It also includes an auxiliary support structure. The auxiliary support structure includes three support seats, a large support (14) in the middle and small supports (17) on both sides. The shape of the support surface of the support seat is parallel to the arc tangent of the weak-rigidity large-arc-shaped casting and is at a certain distance, and the distance is ensured to be controlled within a certain range. There are two small supports (17) in total, and the support surface is composed of a section of tangent line and is arranged on both sides. The basic support surface of the large support (14) is composed of three multi-segments parallel to the arc tangent of the weak-rigidity large-arc-shaped casting; Hydraulic zero-force support cylinders (15) are arranged on the support surfaces of the small supports (17) and the large support (14) at certain positions; The fork hinge support assembly (22) is connected and fixed to the bottom plate (27) by means of screws and pin connectors. The bottom end of the longitudinal pressure plate assembly (24) is rotatably connected to the fork hinge support assembly (22). When in use, the top end of the longitudinal pressure plate assembly (24) is located between two vertically parallel pressure plates at the top end of the large support (14) and is fixed by means of screws and nuts for contact and extrusion. A pressing plate (3) is arranged below the two vertically parallel pressing plates at the top of the large support (14). An oblong hole is provided on the pressing plate (3) for adjusting the clamping position. The clamping bolt (13) passes through the oblong hole. The lower end is screwed into the large support (14) to achieve fixation with the large support (14). The nut (4) is screwed on the upper end. The pressing plate (3) is clamped by rotating the nut (4). The support bolt (6) passes through the pressing plate (3) and is threadedly connected with the pressing plate (3). The lower end is in contact with the upper surface of the large support (14). The support bolt (6) is used to adjust the height of the pressing plate (3) relative to the large support (14) through the thread. The longitudinal pressure plate assembly (24) is provided with a swingable transverse pressure plate assembly (23), and the connection portion between the longitudinal pressure plate assembly (24) and the transverse pressure plate assembly (23) is provided with a mutually perpendicular spherical movable joint, so that bidirectional adaptive floating pressing can be achieved when pressing the ribs of the weak rigidity large arc casting, thereby ensuring the reliability of the pressing contact.

2. The processing method of the weak-rigidity large-arc-shaped casting according to claim 1, characterized in that The spherical support structure adopts spring force adaptive support in combination with hydraulic locking, pneumatic locking, or adopts a pneumatic drive, hydraulic drive, or electric drive spherical support structure with a sensor structure.

3. The machining method of the weakly rigid large-arc-shaped casting according to claim 1, characterized in that The spherical support structure supports the arc segment surface of the weak rigidity large arc casting with a force of 5N through the springs of multiple elastic self-locking devices.

4. The machining method for the weakly rigid large-arc-shaped casting according to claim 1, wherein The described fixed support structure includes an upper support (1), a pressing plate (3), a nut (4), a stud (5), and a support bolt (6). The movable support structure includes a pressing plate (3), a nut (4), a stud (5), a support bolt (6), and a movable support (7). The upper support (1) is fixed to the lower support (2). A long circular hole is provided on the pressing plate (3) for adjusting the pressing position. The stud (5) passes through the long circular hole and is screwed into the upper support (1) at the lower end to achieve fixation with the upper support (1). A nut (4) is screwed onto the upper end, and the pressing plate (3) is pressed by rotating the nut (4). The support bolt (6) passes through the pressing plate (3) and is threadedly connected to the pressing plate (3). The lower end contacts the upper surface of the upper support (1), and the support bolt (6) adjusts the height of the pressing plate (3) relative to the upper support (1) through the thread. The movable support (7) can slide relative to the lower support (2). The upper end of the T-slot nut (9) is connected to the socket head cap screw (8) passing through the movable support (7) to form a sliding support assembly. A sliding pair structure is formed between the T-slot nut (9) and the T-slot structure made on the lower support (2). A circular hole is provided on the pressing plate (3) in the movable support structure. The stud (5) passes through the circular hole and is screwed into the movable support (7) at the lower end to achieve fixation with the movable support (7). A nut (4) is screwed onto the upper end, and the pressing plate (3) is pressed by rotating the nut (4). The support bolt (6) passes through the pressing plate (3) and is threadedly connected to the pressing plate (3). The lower end contacts the upper surface of the lower support (2), and the support bolt (6) adjusts the height of the pressing plate (3) relative to the lower support (2) through the thread. After the movable support (7) is adjusted to the appropriate position, it will be fixed to the lower support (2).

5. The machining method for a weakly rigid large arc-shaped casting according to claim 1, wherein The upper support (1) is connected to the lower support (2) through socket head cap screws (8) and cylindrical fixing pins (10).

6. The machining method of the weak-rigidity large-arc-shaped casting according to claim 1, wherein When the hydraulic zero-force support cylinder (15) is installed and its hydraulic rod can extend or retract by no less than 7 mm when the rear support point is in contact with the theoretical outer shape height of the weak-rigidity large arc-shaped casting. This dimension should be greater than the maximum deviation dimension of the rough blank of the weak-rigidity large arc-shaped casting. In the free state, the spring support force of the hydraulic zero-force support cylinder (15) is less than 0.5 kg per piece. Hydraulic passage holes are designed inside the structures of the small support (17) and the large support (14), and connecting threads are made at the ends of the holes. The hydraulic zero-force support cylinder (15), the accumulator assembly (20), and the hydraulic pump assembly (21) are connected together using a two-way joint (19), a conduit (16), and a four-way joint (18) to form a micro-elastic force support contact and locking control loop.

7. The machining method of the weak-rigidity large-arc-shaped casting according to claim 1, characterized in that, Counterbored holes are provided on the upper surface of the large support (14), and the weak-rigidity large arc-shaped casting is positioned by cooperating with a positioning pin (11) and a positioning bushing (12).

Images