Aero-engine blind cavity nut assembly device

Abstract

The application discloses an aero-engine blind cavity nut assembly device, which comprises a mechanical arm, a screwing assembly for screwing a nut component into the blind cavity, a sliding rail for moving the screwing assembly is arranged on the mechanical arm, a connecting block is fixed on the sliding block of the sliding rail, the connecting block is connected with the screwing assembly and adjusts the phase angle of the screwing assembly, the screwing assembly comprises a power shaft for providing screwing power, a fixed torsion shaft for rotating the nut component, a transmission part arranged between the power shaft and the fixed torsion shaft for transmission, a floating torsion shaft for pushing the clamping nut component, a torsion-resistant fixed shaft for bearing the counter torque generated by the installed nut component, and a visual part arranged in the torsion-resistant fixed shaft for observing the assembly state of the nut component. The application can realize one-time installation of the nut, the check ring and the snap spring, and when different models of nuts are assembled, only the floating torsion shaft and the torsion-resistant fixed shaft need to be replaced, so that the universality is high.

Description

Technical Field

[0001] This invention relates to a nut assembly device, and more particularly to a nut assembly device for a blind cavity of an aero-engine. Background Technology

[0002] The shaft end nut of an aero-engine is a key component for assembling the compressor and turbine rotors. The locking groove and retaining ring groove on the shaft end nut are fitted with retaining rings and snap rings, respectively, to prevent rotation and axial movement of the nut. During the assembly of the shaft end nuts of the low-voltage turbine shaft of an aero-engine, the torque and protection requirements for tightening and loosening these nuts are extremely stringent. Simultaneously, it is necessary to ensure that the "outer lug" on the locking ring engages with the "anti-rotation groove" of the clamping nut, and that the "inner lug" engages with the "anti-rotation groove" on the turbine shaft, thereby achieving a loosening effect and ensuring safe rotor operation.

[0003] Most existing tools are nut-assisted tightening tools. They use torque amplifiers and electric tightening guns to tighten the turbine shaft nuts. The nuts need to be manually installed to the contact position and then tightened with tools. It is impossible to determine whether the anti-rotation grooves of the nuts and turbine shafts are aligned, requiring repeated adjustments. It is impossible to achieve one-time installation. Furthermore, the retaining rings and retaining rings are installed using separate tooling equipment. In other words, the tooling is not universal. Different types of nuts require different types of tooling equipment, resulting in high assembly costs. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide an aero-engine blind cavity internal nut assembly device that can achieve one-time installation, requires no repeated adjustments, and has high versatility.

[0005] Technical solution: The present invention provides a nut assembly device for aero-engine blind cavity, comprising a robotic arm and a tightening assembly that extends into the blind cavity for tightening the nut component. The robotic arm is provided with a slide rail for moving the tightening assembly, and a connecting block is fixed on the slider of the slide rail. The connecting block is connected to the tightening assembly and adjusts the phase angle of the tightening assembly.

[0006] Furthermore, the tightening assembly includes a power shaft for providing tightening power, a fixed torsion shaft for rotating the nut component, a transmission component disposed between the power shaft and the fixed torsion shaft for transmission, a floating torsion shaft for pushing and clamping the nut component, an anti-torsion fixed shaft for bearing the counter-torque generated by installing the nut component, and a vision component disposed inside the anti-torsion fixed shaft for observing the assembly state of the nut component. The floating torsion shaft slides relative to and is detachably connected to the fixed torsion shaft. The anti-torsion fixed shaft passes through the interior of the floating torsion shaft and is detachably connected to the transmission component. The anti-torsion fixed shaft is provided with observation ports that match the vision component, and the number and position of the observation ports correspond to the protrusion at the end of the turbine shaft.

[0007] Furthermore, the front end of the floating torsion shaft is provided with a protrusion that matches the nut component to be assembled, which facilitates the assembly of the nut. The left end of the anti-torsion fixing shaft is provided with a protrusion that matches the end of the turbine shaft, which facilitates fixing the turbine shaft during the assembly of the nut and resisting the counter-torque force during the assembly process.

[0008] Furthermore, the tightening assembly also includes an installation module for assembling the retaining ring and the snap ring. The two ends of the installation module are consistent with the end slots of the nut component to be assembled, and the outer periphery of the installation module is provided with a spring plate to prevent the retaining ring from falling off. The installation module is provided with a push ring inside, the front end of the push ring contacts the snap ring, and the rear end contacts the anti-torsion fixing shaft. After assembling the nut, the installation of the retaining ring and the snap ring can be completed in one go without changing tools or repeatedly adjusting and finding the slot.

[0009] Furthermore, the transmission component includes a gearbox and a fixed disk fixedly installed inside the gearbox. Multiple sets of planetary gears are rotatably mounted on the fixed disk via bearings, and a central gear is rotatably mounted on the right side of the fixed disk. The central gear is located at the center of the multiple sets of planetary gears and meshes with the multiple sets of planetary gears. The output shaft of the power shaft is fixedly connected to the central gear.

[0010] Furthermore, a partial worm gear is fixed to the outside of the gearbox, and guide blocks are provided on both sides of the partial worm gear. A worm is installed on the connecting block, and the worm meshes with the partial worm gear. A guide groove is provided on the inner wall of the connecting block, and the guide block extends into the guide groove and is slidably connected to it.

[0011] Furthermore, the fixed torsion shaft is rotatably connected to the gearbox via bearings, and a first gear is provided at the rear end of the fixed torsion shaft. The first gear is located on the left side of the fixed disk and meshes with the planetary gear. The inner wall of the fixed torsion shaft is provided with a first internal spline, and the outer wall of the floating torsion shaft is provided with a first external spline that mates with the first internal spline.

[0012] Furthermore, the fixed torsion shaft is provided with a preload spring surrounding the outer circumference of the floating torsion shaft, and the preload spring abuts against the end face of the first external spline. The fixed torsion shaft is also provided with a sliding bearing sleeve to guide the sliding of the floating torsion shaft. An anti-detachment block is fixed to the outer circumference of the floating torsion shaft, and an anti-detachment retaining ring that blocks the anti-detachment block is threadedly connected to the left end of the fixed torsion shaft.

[0013] Furthermore, a copper sleeve is connected to the port of the floating torsion shaft by screws. The outer periphery of the copper sleeve is provided with a step, and a spring piece is fitted on the step to prevent the nut component from loosening. The protruding structure and number of the spring piece are consistent with the nut component to be assembled and are matched with the slot at the tail of the nut component.

[0014] Furthermore, the rear end of the anti-torsion fixing shaft is provided with a second external spline, the interior of the fixing disk is provided with a second internal spline adapted to the second external spline, and the exterior of the anti-torsion fixing shaft is also provided with a mounting block that is detachably connected to the fixing disk.

[0015] Furthermore, the vision component includes a telescopically movable camera with a light source and a mounting body, wherein the camera with a light source slides inside the mounting body, and the mounting body is threadedly connected to a fixed disc.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following advantages: The present invention can realize the installation of the nut into the cavity in one go, avoiding the process of manual pre-installation of the nut and repeated adjustment to find the slot; When assembling different types of nuts, the present invention only needs to replace the floating torsion shaft and the anti-torsion fixing shaft, without having to replace the entire set of assembly tools, thus having high versatility; The present invention can also realize the one-time installation of the retaining ring and the snap ring through the setting of the installation module, without having to repeatedly adjust to find the slot; The present invention can resist the counter-torque force of the turbine shaft during the assembly process, thus improving the accuracy of assembly. Attached Figure Description

[0017] Figure 1 This is the front view of the present invention.

[0018] Figure 2 This is a schematic diagram of the connecting block of the present invention.

[0019] Figure 3 This is another structural schematic diagram of the connecting block of the present invention.

[0020] Figure 4 This is a schematic diagram of the tightening assembly of the present invention.

[0021] Figure 5 For the present invention Figure 4 A schematic diagram of the structure in its split state.

[0022] Figure 6 This is a schematic diagram of the structure of the power shaft, fixed torsion shaft and transmission component of the present invention.

[0023] Figure 7 This is a schematic diagram of the structure of the fixed disk of the present invention.

[0024] Figure 8 This is a cross-sectional view of the fixing disc of the present invention.

[0025] Figure 9 This is a cross-sectional view of the fixed torsion shaft of the present invention.

[0026] Figure 10 This is a schematic diagram of the structure of the floating torsion shaft of the present invention.

[0027] Figure 11This is another structural schematic diagram of the floating torsion shaft of the present invention.

[0028] Figure 12 This is a schematic diagram of the anti-torsional shaft of the present invention.

[0029] Figure 13 This is a schematic diagram of the structure of the vision component of the present invention.

[0030] Figure 14 This is a schematic diagram of the installation module of the present invention. Detailed Implementation

[0031] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0032] As shown in the figure, a nut assembly device for a blind cavity of an aero-engine includes a robotic arm 1, a tightening component 2 that extends into the blind cavity for tightening the nut, and a slide rail 3 mounted on the robotic arm 1 for moving the tightening component 2. The fixed part of the slide rail 3 is fixedly mounted on the robotic arm 1, and a connecting block 4 is fixed on the slider of the slide rail 3. After the slide rail 3 is activated, it drives the tightening component 2 to move through the connecting block 4. The connecting block 4 cooperates with the tightening component 2 to adjust the phase angle of the tightening component 2. For some special engine models, the installation depth to bore diameter ratio reaches 10:1, with a depth of nearly 1 meter. It is impossible for a human hand to penetrate deep into the blind cavity for pre-installation. The cooperation of the tightening component 2 and the slide rail 3 allows direct penetration into the blind cavity without the need for manual pre-installation.

[0033] A partial worm gear 235 is fixed to the outside of the gearbox 231, and guide blocks 236 are provided on both sides of the partial worm gear 235. A worm 41 is installed on the connecting block 4, and the worm 41 meshes with the partial worm gear 235. The inner wall of the connecting block 4 is provided with a guide groove 42, and the guide block 236 extends into the guide groove 42 and is slidably connected. When the phase angle of the tightening assembly 2 is adjusted, the worm 41 is rotated, and the worm 41 drives the partial worm gear 235 to rotate, which in turn drives the gearbox 231 to rotate.

[0034] The tightening assembly 2 includes a power shaft 21, a fixed torsion shaft 22, a transmission component 23, a floating torsion shaft 24, an anti-torsion fixed shaft 25, and a vision component 26. The power shaft 21 is a servo tightening shaft that provides tightening power when installing the nut assembly. The fixed torsion shaft 22 is rotatably connected to the power shaft 21 via the transmission component 23. The transmission component 23 includes a gearbox 231 and a fixed disk 232 fixedly installed inside the gearbox 231. Multiple sets of planetary gears 233 are rotatably mounted on the fixed disk 232 via bearings, and a central gear 234 is rotatably mounted on the right side of the fixed disk 232. The central gear 234 is located at the center of the multiple sets of planetary gears 233. The power shaft 21 is meshed with multiple sets of planetary gears 233. The output shaft of the power shaft 21 is fixedly connected to the central gear 234. The fixed torsion shaft 22 is rotatably connected to the gearbox 231 through bearings. The rear end of the fixed torsion shaft 22 is provided with a first gear 221. The first gear 221 is located on the left side of the fixed disk 232 and meshes with the planetary gears 233. The first gear 221 is located at the center of the multiple sets of planetary gears 233. The power shaft 21 drives the central gear 234 to rotate. The central gear 234 drives the planetary gears 233 that mesh with it to rotate. The planetary gears 233 then drive the first gear 221 to rotate, which in turn drives the fixed torsion shaft 22.

[0035] The floating torsion shaft 24 slides relative to and is detachably connected to the fixed torsion shaft 22. The floating torsion shaft 24 passes through the fixed torsion shaft 22, with its right end located inside the fixed torsion shaft 22 and its left end extending to the outside of the fixed torsion shaft 22. The inner wall of the fixed torsion shaft 22 is provided with a first internal spline 222, and the outer wall of the floating torsion shaft 24 is provided with a first external spline 241 that mates with the first internal spline 222. The arrangement of the first internal spline 222 and the first external spline 241 allows the floating torsion shaft 24 to rotate relative to the fixed torsion shaft 22 while the floating torsion shaft 24 and the fixed torsion shaft 22 rotate synchronously. The interior of the fixed torsion shaft 22 is provided with a preload surrounding the outer circumference of the floating torsion shaft 24. Spring 223, and the preload spring 223 abuts against the end face of the first external spline 241. The setting of the preload spring 223 allows the floating torsion shaft 24 to slide inside the fixed torsion shaft 22, which can push the clamping nut component during installation. The fixed torsion shaft 22 is also provided with a sliding bearing sleeve 224 to guide the sliding of the floating torsion shaft 24. An anti-detachment block 242 is fixed on the outer periphery of the floating torsion shaft 24. An anti-detachment retaining ring 225 is threadedly connected to the left end of the fixed torsion shaft 22 to block the anti-detachment block 242. The setting of the anti-detachment retaining ring 225 and the anti-detachment block 242 can prevent the floating torsion shaft 24 from sliding out and falling from the inside of the fixed torsion shaft 22. That is, the floating torsion shaft 24 is detachably connected to the fixed torsion shaft 22 through the anti-detachment retaining ring 225.

[0036] The floating torsion shaft 24 has a protrusion at its front end that is adapted to the nut component to be assembled. A copper sleeve 243 is connected to the end of the floating torsion shaft 24 by a screw. The copper sleeve 243 has consistent protrusions on both sides. The outer periphery of the copper sleeve 243 has a step, and a spring piece 244 is fitted on the step to prevent the nut component from loosening. The protrusion structure and number of the spring piece 244 are consistent with the nut component to be assembled and are matched with the slot at the tail of the nut component. During installation, the spring piece 244 is precisely inserted into the slot at the tail of the nut to be installed to prevent the nut from loosening.

[0037] The left end of the anti-torsion fixed shaft 25 has a protrusion that matches the end of the turbine shaft. During installation, the left end of the anti-torsion fixed shaft 25 is engaged with the turbine shaft. The anti-torsion fixed shaft 25 passes through the interior of the floating torsion shaft 24. The rear end of the anti-torsion fixed shaft 25 is provided with a second external spline 252. The interior of the fixed disk 232 is provided with a second internal spline 237 that matches the second external spline 252. The anti-torsion fixed shaft 25 is used to withstand the counter-torque force generated when installing the nut component. When installing the nut component, the fixed disk 232 remains stationary. The provision of the second external spline 252 and the second internal spline 237 prevents the anti-torsion fixed shaft 25 from rotating relative to the nut component. The exterior of the anti-torsion fixed shaft 25 is also provided with a mounting block 253 that is detachably connected to the fixed disk 232. When installing different types of nuts, only the corresponding anti-torsion fixed shaft 25 and floating torsion shaft 24 need to be replaced, without replacing other components.

[0038] The anti-torsion fixing shaft 25 has a visual element 26 inside for observing the assembly status of the nut component, and the anti-torsion fixing shaft 25 has observation ports 251 that match the visual element 26. The position and number of observation ports 251 correspond to the protrusion at the end of the turbine shaft. The visual element 26 includes a telescopic camera 261 with a light source and a mounting body 262. The camera 261 with a light source slides inside the mounting body 262. The telescopic movement of the camera 261 with a light source can be achieved by a cylinder or other telescopic component. The mounting body 262 is threadedly connected to the fixing plate 232, and the fixing plate 232 has through holes for cables and air pipes for mounting the visual element 26. When the floating torsion shaft 24 drives the copper sleeve 243 to rotate, the visual element 26 monitors the position of the protrusion at the tail of the copper sleeve 243 through the observation ports 251, thereby indirectly obtaining the spatial position of the protrusion at the end of the nut, and thus determining whether the nut protrusion and the turbine shaft protrusion have overlapping grooves.

[0039] The tightening assembly 2 also includes an installation module 27 for assembling a retaining ring and a snap ring. The structure at both ends of the installation module 27 is consistent with the end slots of the nut component to be assembled. The outer periphery of the installation module 27 is provided with a spring plate 271 to prevent the retaining ring from falling off. The installation module 27 is provided with a push ring 272 inside. The front end of the push ring 272 contacts the snap ring and the rear end contacts the anti-torsion fixing shaft 25.

[0040] Working process: First, adjust the robotic arm 1 to make the tightening assembly 2 coaxial with the turbine shaft to be installed. Then, install the nut to be installed on the left end of the floating torsion shaft 24, that is, snap the spring 244 with the nut to be installed. Start the slide rail 3 so that the tightening assembly 2 and the nut to be installed extend into the blind cavity to be installed. Monitor the position of the left end of the floating torsion shaft 24 and the anti-torsion fixed shaft 25 through the vision device 26. Then rotate the worm gear 41 to adjust the phase angle of the tightening assembly 2 so that the anti-torsion fixed shaft 25 corresponds with the turbine shaft to be installed. Then start the slide rail 3 again until the left end of the anti-torsion fixed shaft 25 is snapped with the turbine shaft to be installed. Then turn on the power shaft 21, which drives the fixed torsion shaft 22 to rotate. Due to the action of the first internal spline 222 and the first external spline 241, the floating torsion shaft 24 rotates. The nut is installed at the end of the floating torsion shaft 24 and rotates synchronously with the fixed torsion shaft 22, causing the nut to rotate. At the same time, the floating torsion shaft 24 pushes the nut under the action of the preload spring 223, that is, the nut component rotates and moves forward at the same time to complete the assembly. During the assembly process, the anti-torsion fixed shaft 25 is connected to the fixed plate 232 through the second external spline 252 and the second internal spline 237. Therefore, the anti-torsion fixed shaft 25 will not rotate, thereby preventing the turbine shaft from rotating and bearing the reaction torque during the assembly process. The visual component 26 observes the protrusion position of the copper sleeve 243 of the floating torsion shaft 24 through the observation port 251 of the anti-torsion fixed shaft 25, thereby indirectly obtaining the spatial position of the protrusion at the end of the nut, and then observing whether it is tightened and aligned. After tightening and aligning, the power shaft 21 is closed and the slide rail 3 is activated to move the tightening assembly 2 to the outside of the blind cavity. First, install the retaining ring and snap ring into the mounting module 27. Then, install the mounting module 27 on the left end of the floating torsion shaft 24. Since the tightening component 2 exits the blind cavity directly after assembling the nut, there is no need to readjust its phase angle. Then, start the slide rail 3 to extend the mounting module 27 into the blind cavity. The structure at both ends of the mounting module 27 is consistent with the end slots of the nut component to be assembled. After the mounting module 27 is fully inserted, the protrusion of the mounting module 27 is embedded in the rear end slot of the nut, making the mounting module 27 centered and preventing rotation. The retaining ring slot is aligned. At this time, the floating torsion shaft 24 does not move under the action of the preload spring 223, and the contacting mounting module 27 does not move either. When the anti-torsion fixing shaft 25 goes deeper with the tightening component 2, its shaft head pushes the push ring 272 of the mounting module 27. The push ring 272 drives the snap ring and retaining ring it contacts to move together towards the nut until the snap ring is embedded in the mounting nut slot, and the installation is completed. Because the tightening shaft uses a long, thin shaft design and the anti-torsion shaft is designed internally, it is unrelated to the position and size of the engine rotor's internal dimensions. The only factors affecting its versatility are the thread size and slot structure of the nut to be installed and the turbine shaft.The only difference between different nut models is the size and number of the keyway protrusions on the head, as well as the size and distribution of the slots. Therefore, when assembling different nut models, only the floating torsion shaft 24, the anti-torsion fixing shaft 25, and the mounting module 27 need to be replaced. The specific replacement method is as follows: First, rotate the anti-disengagement retaining ring 225 at the threaded connection of the left end of the fixed torsion shaft 22 to remove the floating torsion shaft 24. Then, remove the mounting block 253 of the anti-torsion fixing shaft 25 and remove the anti-torsion fixing shaft 25. Then, install the new floating torsion shaft 24 and anti-torsion fixing shaft 25 in reverse order. The corresponding mounting module 27 can be directly installed during assembly.

Claims

1. An assembly device for nuts in blind cavities of an aeroengine, comprising a mechanical arm (1), characterized in that: Also include the inside of the blind cavity for tightening nut component tightening assembly (2), the mechanical arm (1) is equipped with a slide rail (3) for moving the tightening assembly (2), the slide rail (3) slider is fixed with the connecting block (4), the connecting block (4) and the tightening assembly (2) are matched with the phase angle of the tightening assembly (2). The connecting block (4) is matched with the phase angle of the tightening assembly (2). The tightening assembly (2) includes a power shaft (21) for providing tightening power, a fixed torsion shaft (22) for rotating the nut component, a transmission member (23) arranged between the power shaft (21) and the fixed torsion shaft (22) for transmission, a floating torsion shaft (24) for pushing the clamping nut component, a torsion resistant fixed shaft (25) for resisting the counter torque generated by the mounting nut component, a visual member (26) arranged inside the torsion resistant fixed shaft (25) for observing the assembly state of the nut component. The floating torsion shaft (24) is opposite to the fixed torsion shaft (22) and is detachably connected. The torsion resistant fixed shaft (25) penetrates the inside of the floating torsion shaft (24) and is detachably connected with the transmission member (23). The torsion resistant fixed shaft (25) is provided with an observation port (251) matched with the visual member (26), and the number and position of the observation port (251) correspond to the protrusions on the end of the turbine shaft. The tightening assembly (2) further comprises an installation module (27) for assembling the check ring and the circlip, the two end structures of the installation module (27) are consistent with the end notches of the nut component to be assembled, and the outer periphery of the installation module (27) is provided with spring sheets (271) for preventing the check ring from falling off. The inside of the installation module (27) is provided with a push ring (272), the front end of the push ring (272) is in contact with the circlip, and the rear end is in contact with the torsion resistant fixed shaft (25).

2. The aeroengine blind cavity nut assembly apparatus of claim 1, wherein: The front end of the floating torsion shaft (24) is provided with a protrusion matched with the nut component to be assembled, and the left end of the torsion resistant fixed shaft (25) is provided with a protrusion matched with the end of the turbine shaft.

3. The aeroengine blind cavity nut assembly apparatus of claim 1, wherein: The transmission member (23) includes a gear box (231), a fixed disc (232) fixedly installed in the gear box (231), a plurality of planetary gears (233) rotatably installed on the fixed disc (232) through bearings, and a central gear (234) rotatably installed on the right side of the fixed disc (232). The central gear (234) is located at the center position of the plurality of planetary gears (233) and is in meshing connection with the plurality of planetary gears (233). The output shaft of the power shaft (21) is fixedly connected with the central gear (234).

4. The aeroengine blind cavity nut assembly apparatus of claim 3, wherein: The outside of the gear box (231) is fixedly provided with a partial worm wheel (235), and the two sides of the partial worm wheel (235) are provided with guide blocks (236). The connecting block (4) is provided with a worm (41). The worm (41) is in meshing connection with the partial worm wheel (235). The inner wall of the connecting block (4) is provided with a guide sliding groove (42). The guide blocks (236) extend into the guide sliding groove (42) and are in sliding connection.

5. The aeroengine blind cavity nut assembly apparatus of claim 3 or 4, wherein: The fixed torsion shaft (22) is rotationally connected with the gear box (231) through a bearing, the rear end of the fixed torsion shaft (22) is provided with a first gear (221), the first gear (221) is located at the left side of the fixed disc (232) and is in meshing connection with the planetary gear (233), the inner wall of the fixed torsion shaft (22) is provided with a first inner spline (222), and the outer wall of the floating torsion shaft (24) is provided with a first outer spline (241) matched with the first inner spline (222); The inside of the fixed torsion shaft (22) is provided with a pre-tightening spring (223) surrounding the outer periphery of the floating torsion shaft (24), and the pre-tightening spring (223) is in abutment with the end face of the first outer spline (241), the inside of the fixed torsion shaft (22) is further provided with a sliding bearing sleeve (224) for guiding the sliding of the floating torsion shaft (24), the outer periphery of the floating torsion shaft (24) is fixedly provided with an anti-disengagement block (242), and the left end port of the fixed torsion shaft (22) is threadedly connected with an anti-disengagement stop ring (225) for blocking the anti-disengagement block (242).

6. The aeroengine blind cavity nut assembly apparatus of claim 1, wherein: The end port of the floating torsion shaft (24) is connected with a copper sleeve (243) through a screw, the outer periphery of the copper sleeve (243) is provided with a step, and the step is provided with an elastic sheet (244) for preventing the nut component from loosening, the protruding structure and the number of the elastic sheet (244) are consistent with the nut component to be assembled and are matched with the clamping groove at the tail of the nut component.

7. The aeroengine blind cavity nut assembly apparatus of claim 3, wherein: The rear end of the anti-torsion fixed shaft (25) is provided with a second outer spline (252), the inside of the fixed disc (232) is provided with a second inner spline (237) matched with the second outer spline (252), and the outside of the anti-torsion fixed shaft (25) is further provided with a mounting block (253) detachably connected with the fixed disc (232).

8. The aeroengine blind cavity nut assembly apparatus of claim 3, wherein: The visual part (26) comprises a light source camera (261) and a mounting body (262) which can be telescopically moved, the light source camera (261) slides in the inside of the mounting body (262), and the mounting body (262) is threadedly connected with the fixed disc (232).

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