Special fixture for special-shaped workpieces and operation method thereof

Abstract

The application relates to a special fixture for special-shaped workpieces and an operating method thereof, relates to the technical field of machining auxiliary equipment, and effectively solves the problems of difficult repeated positioning of special-shaped workpieces and insufficient machining precision; the technical scheme comprises a base, a plurality of supporting plates are arranged in the middle of the base, the supporting plates are arranged at intervals along the length direction of the base, and one side of the supporting plates is arranged to be inclined from top to bottom, a supporting table is detachably arranged on the inclined surface of the supporting plate, and a workpiece mounting plate is arranged on the top of the supporting table. The first positioning and clamping state and the second positioning and clamping state are arranged for the axial hole machining area and the top arc machining area of the special-shaped workpiece respectively, the two positioning states are switched, the workpiece can continue to be machined after the axial hole machining is completed without the need of searching for the machining datum again, accumulated positioning errors generated in the traditional multiple dismounting and mounting processes are effectively avoided, and the position consistency between different machining areas is improved.

Description

Technical Field

[0001] This invention relates to the field of auxiliary equipment for machining, and in particular to a special fixture for irregularly shaped workpieces and its operating method. Background Technology

[0002] With the increasing demands for machining precision, irregularly shaped structural parts are increasingly used in aerospace components, precision mechanical components, and automated equipment due to their complex outlines and multiple machining areas. These irregularly shaped workpieces typically require the simultaneous machining of multiple feature areas such as axial holes and curved surfaces, and there are high requirements for the positional correlation between different machining areas, necessitating the assurance of the relative positional accuracy between each machining feature.

[0003] In existing technologies, for irregularly shaped workpieces with axial holes and top arc-shaped machining areas, a segmented machining method is usually adopted. That is, the axial hole is first machined using one set of fixtures, and then the workpiece is disassembled and another set of fixtures is used to machine the arc-shaped area. However, due to the irregular structure of the irregularly shaped workpiece and the lack of a unified and stable positioning reference, installation deviations are easily generated during the secondary clamping process, resulting in a decrease in the positional accuracy between different machining areas. At the same time, traditional fixtures mostly adopt local clamping methods, which are difficult to provide stable support for the complex force characteristics of irregularly shaped workpieces. During the cutting process, vibration, displacement or elastic deformation are easily generated due to the cutting force, affecting the machining accuracy and surface quality.

[0004] In view of the above, we provide a special fixture for irregularly shaped workpieces and its operation method to solve the above problems. Summary of the Invention

[0005] To address the above issues, this invention provides a special fixture for irregularly shaped workpieces and its operating method. This device is used to process the axial holes and top arc-shaped area on the surface of the irregularly shaped workpiece. It includes a base with multiple support plates in the center. The support plates are spaced apart along the length of the base, and one side is inclined from top to bottom. A support platform is detachably mounted on the inclined surface of the support plate. A workpiece mounting plate is mounted on the top of the support platform. The workpiece mounting plate is used to mount and position the irregularly shaped workpiece, ensuring that the bearing hole axis on the surface of the workpiece remains vertical after mounting.

[0006] The base is provided with a zigzag-shaped support platform on the opposite side of the inclined surface of the support plate, and a first positioning component is adjustablely installed on the top of the support platform;

[0007] The base is provided with a lifting platform on one side of the inclined surface of the support plate. The top of the lifting platform is provided with a moving platform corresponding to the bearing hole of the irregular workpiece. A second positioning component is provided on the lifting platform corresponding to the first positioning component.

[0008] The first and second positioning components are provided on both sides of the bearing hole at the top of the irregular workpiece, and are used to clamp and position the area around the bearing hole in the arc-shaped area at the top of the irregular workpiece; after the lifting platform is disassembled, a mounting platform is provided on the base of the disassembly area, and the top area of ​​the mounting platform is located on both sides of the arc-shaped processing area; clamping platforms are installed on both sides of the platform, one clamping platform maintains a lateral limiting gap of 0.005~0.01mm with the edge of the irregular workpiece, and the other clamping platform is kept in close contact with the irregular workpiece;

[0009] The first positioning component, the lifting platform, the moving platform and the second positioning component form a first positioning and clamping state for machining the bearing hole of the irregular workpiece.

[0010] The clamping platform and the mounting platform cooperate to form a second positioning and clamping state for machining the arc-shaped area at the top of the irregular workpiece; and during operation, a contour piece is set every 25mm on the back of the arc-shaped machining area to form a bottom support, and the flatness of the contact surface of the contour piece is 0.015mm.

[0011] Preferably, the bottom of the inclined surface of the support plate protrudes upward to support the bottom of the workpiece mounting plate.

[0012] Preferably, the first positioning element includes a drive shaft, a turning shaft, and a clamping shaft;

[0013] The drive shaft is slidably connected to the support platform; wherein, the turning shaft is divided into area A and area B along the axial direction, and area A is inclined; the upper surface of area B is consistent with the inclination direction of area A, and its lower surface extends from the front end along the inclination direction of area A to the middle, and then extends downward in an arc transition, so that the lower surface of area B forms an arc-shaped structure that bulges upward in the middle.

[0014] The turning shaft extends vertically upward from the end away from area A to form a clamping shaft. During its upward extension, one side extends outward through an arc to increase its width. The clamping shaft is set to fit the surface of the irregular workpiece.

[0015] Preferably, a square opening is provided on the upper surface at the junction of area A and area B.

[0016] Preferably, the irregularly shaped workpiece has an axial hole and a back shaft around its periphery, and multiple back shafts are connected to the corresponding first positioning member, moving table or second positioning member through screw holes.

[0017] Preferably, the mounting platform includes a lower shaft and two upper shafts, the two upper shafts are spaced apart along the width direction of the lower shaft and are detachably connected to the lower shaft by bolts; both ends of the lower shaft are fixedly mounted on the base by bolts; the lower middle part of the lower shaft has a hollowed-out part, and a through mounting gap is formed between the two upper shafts, thereby forming a hollowed-out structure in the middle.

[0018] Operating instructions for special fixtures for irregularly shaped workpieces:

[0019] Step 1: First, install and fix the support plate, then install the support platform on the support plate, and finally install and fix the workpiece mounting plate on the support platform.

[0020] Step 2: Install the first positioning component, the lifting platform, the moving platform, and the second positioning component to machine the axial hole corresponding to the axial hole of the irregular workpiece;

[0021] Step 3: After completing the axial hole machining, remove all the workpieces connected to it. Then, position and install the clamping table, mounting table, and contoured parts corresponding to the arc-shaped area. Separate the cutting allowance on both sides of the arc-shaped area into separate processes to reduce the single cutting force. State 1: Only machine the outer arc surface; State 2: Flip / switch the clamps to machine the inner arc groove; Single cutting depth 0.3~0.4mm, radial cutting force 420~550N.

[0022] The beneficial effects of the above technical solution are as follows:

[0023] (1) This application sets a first positioning clamping state and a second positioning clamping state for the axial hole machining area and the top arc machining area of ​​the irregular workpiece respectively. By switching between the two positioning states, the workpiece can continue to perform arc machining without having to find the machining datum again after completing the axial hole machining, effectively avoiding the cumulative positioning error generated during the traditional multiple disassembly and assembly process, and improving the positional consistency between different machining areas.

[0024] (2) For machining the top arc area, a positioning method is formed by clamping on one side and limiting the micro gap on the other side through the clamping tables on both sides. This ensures the positioning accuracy of the workpiece while releasing some of the machining stress. Combined with the staged cutting method, the single machining load is reduced, so that the workpiece remains stable within a small displacement range, thereby improving the machining accuracy and surface quality of complex curved surfaces.

[0025] (3) A second positioning and clamping state is formed by the mounting table, clamping table and contouring parts. The clamping table provides lateral limiting clamping for the irregular workpiece, and the contouring parts are set at intervals according to the back contour of the arc processing area to form continuous support for the bottom of the workpiece, so that the processing area is more uniformly stressed, effectively reducing vibration, sinking and elastic deformation generated during processing, and improving the processing quality of the arc surface. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the first positioning element of the present invention;

[0027] Figure 2 This is a schematic diagram of the second positioning element of the present invention;

[0028] Figure 3 This is a schematic diagram of the mounting platform structure of the present invention;

[0029] Figure 4 This is a schematic diagram of the contouring component structure of the present invention.

[0030] In the diagram: 1001, irregular workpiece; 1, base; 2, support plate; 3, support platform; 4, workpiece mounting plate; 5, bearing platform; 6, first positioning component; 7, lifting platform; 8, moving platform; 9, second positioning component; 10, mounting platform; 101, lower shaft; 102, upper shaft; 11, clamping platform; 12, contouring component; 13, back shaft; 61, drive shaft; 62, turning shaft; 621, area A; 622, area B; 63, clamping shaft; 6211, square opening. Detailed Implementation

[0031] The foregoing and other technical contents, features and effects of the present invention are described in conjunction with the appendix below. Figures 1 to 4 As will be clearly shown in the detailed description of the embodiments, all structural contents mentioned in the following embodiments are based on the accompanying drawings.

[0032] This application proposes a special fixture for irregularly shaped workpieces and its operating method to solve the problem of deviation in irregularly shaped machining.

[0033] This device is used to process two parts: the axial hole on the surface of the irregularly shaped workpiece 1001 and the arc-shaped area on the top. In existing methods, these two parts are processed separately without positioning. After processing a single area, the workpiece is replaced with a fixture for further processing. However, repositioning and reinstalling the workpiece can easily cause deviations in the processing after reinstallation, leading to instability in subsequent installations. To solve this problem, this application provides a dedicated fixture to enable the processing and installation of this device. The two processing areas remain fixed in position, and processing at either position is unaffected.

[0034] The special fixture for this irregularly shaped workpiece is as follows:

[0035] For reference Figure 1 It includes a base 1, and a plurality of support plates 2 are provided in the middle of the base 1. The plurality of support plates 2 are arranged at equal intervals along the length of the base 1 and are located in the middle area of ​​the base 1, with gaps reserved on both wide sides to facilitate the subsequent installation of parts.

[0036] Support plates 2 are spaced along the length of base 1, and one side of them is inclined from top to bottom. The angle of inclination is designed according to the actual irregular workpiece being processed. Support platforms 3 are detachably installed on the inclined surface of support plates 2. The design of support platforms 3 fills the deficiencies in the design of the inclination angle of the base and makes up for the inclination defects. The side of support platform 3 facing support plate 2 is fitted with support plate 2, but the side away from support plate 2 is fitted with workpiece mounting plate 4. At the same time, the side that is fitted with workpiece mounting plate 4 is not limited in design, and is designed based on the surface shape of the irregular workpiece 1001.

[0037] A workpiece mounting plate 4 is installed on the top of the support platform 3. The workpiece mounting plate 4 is used to install and position irregularly shaped workpieces. After the workpiece mounting plate 4 is installed on the support platform 3, the axes of multiple bearing holes on the surface of the irregularly shaped workpiece 1001 remain vertical, facilitating subsequent horizontal machining and ensuring stability. Simultaneously, with the axis holes remaining vertical, the arc-shaped machining area on the top of the irregularly shaped workpiece 1001 is also vertically and horizontally positioned. This support ensures that both structural components remain vertical during subsequent installation, better facilitating the installation of subsequent parts.

[0038] Furthermore, the bottom of the inclined surface of the support plate 2 protrudes upwards to support the bottom of the workpiece mounting plate 4; it is not only designed with an inclined surface, but also with an upward protrusion.

[0039] For reference Figure 1-2 In the axial hole-based installation, a zigzag bearing platform 5 is further provided on the opposite side of the base 1 located on the inclined surface of the support plate 2. The zigzag design can reduce the load-bearing capacity of the base 1 while maintaining stability.

[0040] A first positioning component 6 is adjustablely mounted on the top of the support platform 5. The first positioning component 6 is installed against the side of the axial hole in the top arc-shaped machining area. The first positioning component 6 has a bent design to reduce the risk of structural deformation. If it completely corresponds to the design of the support platform 5, the area that the base 1 can bear and the distance between it and the irregular workpiece 1001 are set. At the same time, considering the inclined design of the workpiece mounting plate 4, the top area of ​​the workpiece mounting plate 4 needs to be avoided to avoid its structure. If the machining force is pushed onto the workpiece mounting plate 4 during operation, and the workpiece mounting plate 4 is then transported to the irregular workpiece 1001, it is easy to cause the workpiece to deform during processing. Therefore, to avoid this problem, the first positioning component 6 is designed to be bent and is composed of three parts: a drive shaft 61, a turning shaft 62, and a clamping shaft 63.

[0041] For reference Figure 1-2 The drive shaft 61 is slidably connected to the support platform 5, and the two form a stable guiding relationship, so that the drive shaft 61 always moves in a straight line along the preset axis during the front and rear adjustment process, effectively avoiding the phenomenon of swaying, tilting or axis deviation during the adjustment process, thereby ensuring the subsequent positioning accuracy and improving the repeatability and overall operational stability of the clamping mechanism.

[0042] The pivot shaft 62 is axially divided into section A 621 and section B 622, with section A 621 being inclined. The upper surface of section B 622 extends along the inclined direction of section A 621, and its lower surface extends from the front end along the inclined direction of section A 621 to the middle, then smoothly transitions downwards with an arc, forming an arc-shaped support structure with an upward bulge in the middle. This structural design makes the transition from the inclined section to the clamping section of the pivot shaft 62 smoother, avoiding stress concentration at traditional right-angle bends and improving the overall structural strength and bending resistance of the pivot shaft 62. Simultaneously, the arc-shaped support structure increases the support area at the root of the clamping shaft 63, allowing for more adequate support when the clamping shaft 63 is under force, effectively reducing the possibility of swaying, shifting, or deformation of the clamping shaft 63 under clamping force, thus improving clamping stability and long-term reliability.

[0043] The end of the pivot shaft 62 furthest from area A 621 extends vertically upward to form a clamping shaft 63. As the clamping shaft 63 extends upward, its side facing the irregularly shaped workpiece 1001 expands outward via an arc to form a widened portion, further increasing the contact area between the clamping shaft 63 and the irregularly shaped workpiece 1001 and adapting it to the contour of the workpiece 1001. By increasing the contact width and adopting an arc transition structure, not only can the clamping force distribution be more uniform, reducing local stress concentration and avoiding indentations or damage to the surface of the irregularly shaped workpiece 1001, but it can also effectively limit the workpiece's wobbling and displacement during processing, improving clamping reliability, ensuring positional consistency between different processing stations such as bearing holes and arc-shaped surfaces, and further improving processing accuracy and product qualification rate.

[0044] Furthermore, a square opening 6211 is provided on the upper surface of the junction between area A 621 and area B 622. The square opening 6211 and the arc-shaped transition structure on the lower surface of area B 622 cooperate with each other to ensure the overall structural strength while creating a stress-relieving effect on the junction area. This effectively disperses the bending stress and impact stress generated during the clamping process, preventing stress from concentrating at the turning point for a long time, which could lead to cracks or deformation. This improves the bending strength, fatigue resistance and long-term stability of the turning shaft 62.

[0045] A lifting platform 7 is provided on one side of the inclined surface of the support plate 2, located on the base 1. The lifting platform 7 is used to increase the installation support height, and its top is equipped with a movable platform 8 corresponding to the bearing hole of the irregular workpiece 1001. The movable platform 8 can be adjusted back and forth according to the position of the bearing hole of the irregular workpiece 1001 to achieve precise alignment with the bearing hole. By lifting the movable platform 7, the overall length of the movable platform 8 is reduced, its support rigidity and load-bearing stability are improved, and the movable platform 8 is less prone to shaking or deformation during adjustment, thereby ensuring the positioning accuracy of the bearing hole.

[0046] A second positioning element 9 is provided on the raised platform 7 at the position corresponding to the first positioning element 6. The second positioning element 9 is set with the axial hole corresponding to the arc-shaped machining area on the top of the irregular workpiece 1001, and cooperates with the first positioning element 6 to form a double-point clamping and positioning of the irregular workpiece 1001. Through the joint action of the two positioning elements, not only is the axial hole installed, but the irregular workpiece 1001 is also fixed on the upper side by the workpiece mounting plate 4. The second positioning element 9 forms a support point on the opposite side, and the moving platform 8 on both sides also shares the support force, so that the structure completes the machining and support work, effectively reducing unnecessary structural installation and lowering the overall weight. A stable force balance is formed during the machining process, effectively limiting the workpiece from moving forward and backward, warping and offset, and improving the machining stability and positioning accuracy of the bearing hole and the arc-shaped machining area on the top.

[0047] Furthermore, the irregular workpiece 1001 is provided with a back shaft 13 around each axial hole. Multiple back shafts 13 are connected and fixed to the corresponding first positioning member 6, moving table 8 or second positioning member 9 through screw holes, so that the clamping force is directly applied to the high-strength area around the axial hole, which further improves the clamping firmness of the irregular workpiece 1001, avoids loosening or displacement during processing, and ensures the consistency between each processing position.

[0048] In the above-described configuration, the first positioning element 6, the lifting platform 7, the moving platform 8, and the second positioning element 9 cooperate to form the first positioning and clamping state for machining the bearing hole of the irregular workpiece 1001. Specifically, the first positioning element 6 and the second positioning element 9 respectively limit and clamp the front and rear sides of the irregular workpiece 1001, the moving platform 8 provides support and positioning for the bearing hole area, and the lifting platform 7 provides a high-rigidity support foundation for the moving platform 8. This ensures that the irregular workpiece 1001 forms a stable four-point positioning support structure during the bearing hole machining process, thereby effectively improving clamping stability, positioning accuracy, and machining consistency.

[0049] After the axial hole of the irregular workpiece 1001 is machined, the first positioning component 6, the moving table 8, and the second positioning component 9 are removed to release the axial hole machining area and reserve machining space for the top arc-shaped area. Subsequently, the mounting table 10 is installed on the base 1 of the disassembly area. The top of the mounting table 10 is located on both sides of the top arc-shaped machining area of ​​the irregular workpiece 1001 to support the subsequent clamping components.

[0050] For reference Figure 3-4The mounting table 10 has clamping platforms 11 installed on both sides. One clamping platform 11 maintains a lateral limiting gap of 0.005 to 0.01 mm with the outer edge of the irregular workpiece 1001, allowing the irregular workpiece 1001 to obtain a small amount of compensation space during processing. This ensures the limiting accuracy while avoiding local extrusion deformation due to excessive clamping. The other clamping platform 11 is tightly attached to the outer edge of the irregular workpiece 1001, applying a stable clamping force to the irregular workpiece 1001. Through this combination of tight clamping on one side and limiting with a small gap on the other, the irregular workpiece 1001 can be reliably positioned while releasing some cutting stress. This effectively counteracts the maximum horizontal radial cutting force of approximately 650 N generated during processing, keeping the workpiece displacement in the XY direction within 0.007 mm, thereby ensuring the processing accuracy and dimensional consistency of the top arc-shaped area.

[0051] The clamping table 11 and the mounting table 10 cooperate to form a second positioning and clamping state for machining the top arc-shaped area of ​​the irregular workpiece 1001. This positioning and clamping state can switch between the first positioning and clamping state without recalibrating the workpiece datum, thus completing the transition from axial hole machining to machining the top arc-shaped area, improving machining efficiency, and ensuring positional accuracy between the two machining processes.

[0052] To further improve the load-bearing capacity during machining of the top arc-shaped area, a contouring component 12 is installed at 25mm intervals along the length of the back side of the arc-shaped machining area. Each contouring component 12 is adapted to the bottom contour of the irregular workpiece 1001, and the flatness of its supporting and contacting surface is controlled within 0.015mm. Multiple contouring components 12 together form a continuous contouring support structure, making the bottom of the irregular workpiece 1001 more evenly stressed, effectively dispersing the cutting load generated during machining, preventing the workpiece from sinking, vibrating, or elastically deforming due to local suspension, improving the overall rigidity and vibration resistance of the top arc-shaped area during machining, and further ensuring the machining accuracy, surface quality, and machining consistency of the arc contour.

[0053] Furthermore, the mounting table 10 includes a lower shaft 101 and two upper shafts 102. The two upper shafts 102 are spaced apart along the width direction of the lower shaft 101 and are detachably connected to the lower shaft 101 by bolts. The two upper shafts 102 provide the mounting base for the clamping table 11, allowing the clamping table 11 to be installed on both sides of the arc-shaped processing area of ​​the irregular workpiece 1001 to achieve lateral positioning and clamping of the workpiece. The detachable connection structure between the upper shafts 102 and the lower shafts 101 facilitates the adjustment or replacement of the positions of the upper shafts 102 and the clamping table 11 according to the processing requirements of irregular workpieces 1001 of different specifications, thereby improving the applicability of the mounting table 10.

[0054] Both ends of the lower shaft 101 are fixed to the base 1 with bolts, forming a stable and reliable connection between the mounting platform 10 and the base 1, thus improving the overall support rigidity during processing. A hollow section is formed in the lower middle part of the lower shaft 101, creating a through-hole between the two upper shafts 102, resulting in a hollow structure in the center of the mounting platform 10. This hollow design effectively reduces the structural weight while ensuring the overall load-bearing strength of the mounting platform 10, and provides clearance for the processing area, preventing interference between the mounting platform 10 and the processing tools or workpiece structure. Simultaneously, the through-hole structure facilitates the removal of debris generated during processing, improving the cleanliness of the processing environment and further enhancing the stability of equipment operation.

[0055] In the above description, the mounting table 10, clamping table 11, and contouring component 12 together form the second positioning and clamping state for machining the top arc-shaped area of ​​the irregular workpiece 1001. The mounting table 10 provides the mounting reference, the clamping table 11 provides lateral limiting and clamping positioning, and the contouring component 12 provides continuous bottom support. These three components work together to form a three-dimensional stable force system of upper clamping, lateral limiting, and bottom support for the irregular workpiece 1001 during the machining of the arc-shaped area. Combined with the first positioning and clamping state, the machining of the bearing hole and the top arc-shaped area can be completed in a single clamping operation under both positioning states, avoiding cumulative positioning errors caused by repeated clamping and improving the machining accuracy, efficiency, and product consistency of the irregular workpiece.

[0056] In view of the above, the operation method of this special fixture for irregularly shaped workpieces is as follows:

[0057] Step one: First, fix the base 1 on the workbench of the processing equipment. According to the overall structural dimensions of the irregular workpiece 1001, install multiple support plates 2 on the base 1 according to the preset positions, so that each support plate 2 forms a stable support foundation. Then, install and fix the support platform 3, which matches the inclined surface of the support plate 2, on the support plate 2, and install the workpiece mounting plate 4 on the top of the support platform 3, so that the workpiece mounting plate 4 forms the initial placement and positioning reference for the irregular workpiece 1001.

[0058] After installation, place the irregular workpiece 1001 to be processed on the workpiece mounting plate 4, so that the bottom of the irregular workpiece 1001 fits against the workpiece mounting plate 4, and adjust the initial position according to the shape of the workpiece so that the subsequent axial hole processing area is within the preset processing range.

[0059] Step 2: After the irregular workpiece 1001 is placed and positioned, the first positioning component 6, the lifting platform 7, the moving platform 8 and the second positioning component 9 are installed in sequence at the corresponding positions of the base 1 according to the position of its axial hole.

[0060] In this process, by adjusting the position of the moving stage 8, its top support area corresponds to the position of the axial hole to be processed on the irregular workpiece 1001; at the same time, the first positioning member 6 and the second positioning member 9 correspond to the positioning areas on the front and rear sides of the irregular workpiece 1001, respectively, and the two cooperate to form a front-to-back direction limiting clamp on the irregular workpiece 1001.

[0061] Furthermore, the back shaft 13, which is arranged around the axial hole of the irregular workpiece 1001, is connected to the first positioning member 6, the moving stage 8, and the second positioning member 9 through screw holes, so that the clamping force is applied to the area around the axial hole, thereby forming a stable first positioning and clamping state. It should be noted that the shape of the back shaft 13 is not limited, as long as it is adapted to the size and width of the connected structure.

[0062] In this state, the axial hole of the irregular workpiece 1001 is machined using the machining equipment. During the machining process, the first positioning member 6 and the second positioning member 9 restrict the front-to-back displacement of the workpiece. The moving table 8 provides bottom support for the machining area, and the lifting table 7 increases the support rigidity of the moving table 8, so that the irregular workpiece 1001 remains stable during drilling, boring or finishing, and avoids hole displacement caused by cutting vibration.

[0063] Step 3: After the axial hole machining is completed, remove the first positioning component 6, the lifting platform 7, the moving platform 8, the second positioning component 9, and related connecting components corresponding to the axial hole machining, so as to release the axial hole machining area.

[0064] Subsequently, based on the position of the arc-shaped machining area on the top of the irregular workpiece 1001, the mounting platform 10 is installed on the corresponding disassembly area of ​​the base 1, and the clamping platform 11 is installed on both sides of the mounting platform 10. At the same time, the contouring parts 12 are arranged at intervals on the back of the arc-shaped machining area.

[0065] The mounting platform 10 provides mounting support for the clamping platform 11, enabling the clamping platforms 11 on both sides to form a positioning relationship with the sides of the irregular workpiece 1001. One clamping platform 11 maintains a slight gap with the irregular workpiece 1001 for limiting positioning, while the other clamping platform 11 maintains a close fit with the irregular workpiece 1001, allowing the irregular workpiece 1001 to adapt to slight force changes during the processing while ensuring positioning accuracy.

[0066] Meanwhile, multiple contoured parts 12 located on the back of the arc-shaped processing area are fitted to fit the bottom contour of the irregular workpiece 1001, forming continuous support for the arc-shaped processing area, thereby forming a second positioning and clamping state together with the clamping table 11.

[0067] In the second positioning and clamping state, the top arc-shaped area of ​​the irregular workpiece 1001 is machined. In order to reduce the radial force during a single cutting process, the machining allowance of the arc-shaped area is cut in stages.

[0068] First, process state one:

[0069] The clamping direction is adjusted to the machining position corresponding to the outer arc surface, and only the outer arc surface area of ​​the irregular workpiece 1001 is cut. During the machining process, the clamping table 11 provides lateral limit and the contouring part 12 provides bottom support, so that the radial load generated by cutting is evenly transmitted to the mounting table 10 and the base 1, reducing workpiece vibration.

[0070] Then proceed with state two processing:

[0071] According to the processing requirements of the inner groove, the base 1 is rotated so that the irregular workpiece 1001 is in a suitable positioning state for inner processing, and the inner groove area of ​​the arc is processed.

[0072] During the machining of the arc-shaped area, the depth of cut in a single operation is controlled within the range of 0.3 to 0.4 mm, and the radial cutting force generated in a single operation is controlled within the range of 420 to 550 N. This avoids workpiece deformation or clamping instability caused by excessive cutting force, thereby improving the machining accuracy and surface quality of the arc-shaped surface.

[0073] Finally, after the axial hole and the top arc-shaped area have been machined, the clamping table 11, the contour piece 12 and the relevant positioning components are released in sequence, and the machined irregular workpiece 1001 is removed.

[0074] Through the above processing, the axial hole is processed using the first positioning and clamping state, and the top arc-shaped area is processed using the second positioning and clamping state. Without the need to re-align the processing datum, continuous processing of multiple areas of the irregular workpiece 1001 is achieved, which effectively reduces the positioning error caused by repeated clamping and improves processing efficiency, processing accuracy and product consistency.

[0075] The above description is only for illustrating the present invention and should be understood as not being limited to the above embodiments. Various modifications that conform to the spirit of the present invention are within the protection scope of the present invention.

Claims

1. A special fixture for irregularly shaped workpieces, used for machining axial holes and top arc-shaped areas on the surface of the irregularly shaped workpiece (1001); characterized in that: Includes a base (1), and a plurality of support plates (2) are provided in the middle of the base (1). The support plates (2) are spaced apart along the length of the base (1), and one side of them is inclined from top to bottom. A support platform (3) is detachably installed on the inclined surface of the support plate (2). A workpiece mounting plate (4) is installed on the top of the support platform (3). The workpiece mounting plate (4) is used to install and position irregular workpieces so that the bearing hole axis on the surface of the irregular workpiece remains vertical after installation. The base (1) is provided with a zig-shaped support platform (5) on the opposite side of the inclined surface of the support plate (2), and a first positioning component (6) is adjustablely installed on the top of the support platform (5). The base (1) is provided with a lifting platform (7) on one side of the inclined surface of the support plate (2). The top of the lifting platform (7) is provided with a moving platform (8) corresponding to the bearing hole of the irregular workpiece. The lifting platform (7) is provided with a second positioning member (9) corresponding to the first positioning member (6). The first positioning component (6) and the second positioning component (9) are provided on both sides of the bearing hole at the top of the irregular workpiece, and are used to clamp and position the bearing hole periphery area provided in the arc area at the top of the irregular workpiece; after the lifting platform (7) is disassembled, an installation platform (10) is provided on the base (1) of the disassembly area, and the top area of ​​the installation platform (10) is located on both sides of the arc processing area; clamping platforms (11) are installed on both sides of the area, one clamping platform (11) maintains a lateral limiting gap of 0.005~0.01mm with the edge of the irregular workpiece, and the other clamping platform (11) is kept in close contact with the irregular workpiece; Among them, the first positioning component (6), the lifting platform (7), the moving platform (8) and the second positioning component (9) form the first positioning and clamping state for machining the bearing hole of the irregular workpiece (1001); The clamping platform (11) and the mounting platform (10) cooperate to form a second positioning and clamping state for machining the top arc area of ​​the irregular workpiece; and during operation, a contour piece (12) is set every 25mm on the back of the arc area machining area to form a bottom support, and the contour piece (12) supports a flatness of 0.015mm on the contact surface.

2. The special fixture for irregularly shaped workpieces according to claim 1, characterized in that, The bottom of the inclined surface of the support plate (2) protrudes upward to support the bottom of the workpiece mounting plate (4).

3. The special fixture for irregularly shaped workpieces according to claim 1, characterized in that, The first positioning component (6) includes a drive shaft (61), a turning shaft (62), and a clamping shaft (63). The drive shaft (61) is slidably connected to the support platform (5); wherein, the turning shaft (62) is divided into area A (621) and area B (622) along the axial direction, and area A (621) is inclined; the upper surface of area B (622) is consistent with the inclined direction of area A (621), and its lower surface extends from the front end along the inclined direction of area A (621) to the middle, and then extends downwards through an arc transition, so that the lower surface of area B (622) forms an arc-shaped structure with the middle part raised upwards; The turning shaft (62) extends vertically upward from one end away from area A (621) to form a clamping shaft (63). During its upward extension, one side extends outward through an arc to increase its width. The clamping shaft (63) is set to fit the surface of the irregular workpiece (1001).

4. The special fixture for irregularly shaped workpieces according to claim 3, characterized in that, A square opening (6211) is provided on the upper surface at the junction of area A (621) and area B (622).

5. The special fixture for irregularly shaped workpieces according to claim 1, characterized in that, The irregular workpiece (1001) has an axial hole and a back shaft (13) around its periphery. Multiple back shafts (13) are connected to the corresponding first positioning member (6), moving table (8) or second positioning member (9) through screw holes.

6. The special fixture for irregularly shaped workpieces according to claim 1, characterized in that, The mounting platform (10) includes a lower shaft (101) and two upper shafts (102). The two upper shafts (102) are spaced apart along the width direction of the lower shaft (101) and are detachably connected to the lower shaft (101) by bolts. The two ends of the lower shaft (101) are fixedly installed on the base (1) by bolts. The lower middle part of the lower shaft (101) is provided with a hollow part, and a through installation gap is formed between the two upper shafts (102), thereby forming a hollow structure in the middle.

7. The operating method of the special fixture for irregularly shaped workpieces according to any one of claims 1-6, characterized in that: Step 1: First, install and fix the support plate (2), then install the support platform (3) on the support plate (2), and then install and fix the workpiece mounting plate (4) on the support platform (3); Step 2: Install the first positioning component (6), the lifting platform (7), the moving platform (8), and the second positioning component (9) on the axial hole of the irregular workpiece (1001) to perform axial hole machining; Step 3: After completing the axial hole machining, remove all the workpieces connected to it. Then, position and install the clamping table (11), mounting table (10), and contour part (12) in the corresponding arc area. Then, split the cutting allowance of the arc surface on both sides of the arc area into separate processes to reduce the single cutting force. State 1: Only machine the outer arc surface. State 2: Flip / switch the clamps to machine the inner groove of the arc. Single cutting depth 0.3~0.4mm, radial cutting force 420~550N.

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