An automatic tightening robot for connecting bolts of high-pressure turbine rotors in aircraft engines

Abstract

This invention relates to an automatic tightening robot for connecting bolts of high-pressure turbine rotors in aero-engines, belonging to the field of automated assembly technology. It includes: a workpiece positioning and clamping system for positioning, clamping, and fixing the workpiece to be assembled, providing a stable operating reference for the tightening robot; an assembly system for moving, positioning, and tightening the workpiece at the tightening end; and an automatic grease coating system for applying grease to the threads before bolt assembly. It also includes a contour simulation system for precision calibration and torque testing before robot operation. This invention improves the process consistency and tightening torque accuracy of high-pressure turbine rotor connecting bolt tightening quality, and increases production efficiency; simultaneously, it reduces manual intervention and lowers labor intensity.

Description

Technical Field

[0001] This invention belongs to the field of automated assembly technology, and in particular relates to an automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines. Background Technology

[0002] In the core of an aero-engine, the high-vortex rotor is formed by fastening a multi-stage bladed disk rotor with dozens of bolts and nuts evenly distributed along the axis. The fastening quality of the threaded connections directly determines the rotor assembly performance and the overall reliability of the engine.

[0003] During the assembly of high-vortex rotors, bolts are usually pre-installed before the rotor components are connected. In a few special cases, bolt installation and tightening need to be completed inside the rotor. Due to the limitations of the engine structure, the available space inside the high-vortex rotor is extremely limited. The feed channel is narrow, the tightening operation space is limited, and the diameter of the internal fasteners is large. This leads to three core challenges for automatic tightening equipment: narrow channel, small space, and easy interference.

[0004] Currently, the installation and tightening of high-vortex rotor connecting bolts in the industry are still mainly done manually, lacking dedicated automated tightening equipment. Manual operation has the following significant drawbacks: 1) Poor assembly quality consistency, making it impossible to guarantee the uniformity of all bolt tightening processes; 2) Insufficient tightening torque accuracy, as manual operation makes it difficult to accurately control torque output, easily leading to over-tightening or under-tightening of bolts; 3) Low production efficiency, as manual operation in confined spaces is difficult and time-consuming; 4) High labor intensity, complex working environment, and limited safety and stability of manual operation.

[0005] Therefore, there is an urgent need to develop a special automatic tightening equipment that is adapted to the internal working environment of high-vortex rotors, has a high degree of automation, and combines tightening accuracy and efficiency. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides an automatic tightening robot for connecting bolts of high-pressure turbine rotors in aero engines.

[0007] An automated tightening robot for connecting bolts of a high-pressure turbine rotor in an aero-engine includes:

[0008] The workpiece positioning and clamping system positions, clamps, and fixes the workpiece to be assembled, providing a stable operating reference for the tightening robot;

[0009] An assembly system for moving, positioning, and tightening the working end of the assembly;

[0010] An automatic grease coating system applies grease to the threads before bolt assembly.

[0011] The workpiece positioning and clamping system includes a fixed support and a workpiece bearing part installed on the fixed support. The workpiece bearing part can slide and rotate along the fixed support. The clamping plate can be raised and lowered and connected to the fixed support for clamping from the top of the workpiece.

[0012] The assembly system includes a circumferential indexing component and an axial feed component mounted on the circumferential indexing component. A radial synchronous feed component is mounted on the axial feed component, and a tightening component is located at the end of the radial synchronous feed component, realizing three-dimensional movement and tightening of the tightening working end. The axial feed component, circumferential indexing component, and radial synchronous feed component all have built-in encoders. Rotary and linear motions are controlled by photoelectric switches, forming a closed-loop detection to achieve precise alignment between the tightening working end and the bolt hole.

[0013] The radial synchronous feed assembly includes two sets of tightening assemblies with identical structures. The radial synchronous feed assembly is set on the axial feed assembly through a transmission mechanism, and is synchronously fed in the opposite direction through the transmission mechanism.

[0014] The tightening assembly includes a tightening power source, a cap-recognition transmission assembly connected to the output end of the tightening power source via a swing transmission assembly, and a tightening sleeve installed at the output end of the cap-recognition transmission assembly. The swing transmission assembly adopts an L-shaped force transmission structure to transmit torque to the tightening sleeve via the cap-recognition transmission assembly. During tightening, the tightening power source drives the cap-recognition transmission assembly and the swing transmission assembly to swing as a whole to complete the torque transmission.

[0015] The tightening assembly is equipped with an endoscope embedding and guiding structure at its end for installing an endoscope to assist in observing the bolt cap and tightening status in a narrow space.

[0016] The assembly system also includes an automatic bolt feeding assembly, comprising a fixing part mounted on the circumferential indexing assembly, a stocking tray mounted on the fixing part, bolts being hung circumferentially on the edge of the bolt stocking tray, the edge having a corresponding semi-opening; a line pushing assembly corresponding to the bottom of the bolts, pushing the bolts upwards from the stocking tray away from the stocking tray for feeding; a gripping assembly is provided on the swing transmission assembly, the gripping assembly being moved to the bolts away from the stocking tray by the linkage of the circumferential feed cylinder and the horizontal cylinder, clamping and gripping the bolts and conveying them to the tightening sleeve to complete the cap recognition.

[0017] The automatic grease application system includes a grease gun, a horizontal feed cylinder for the grease gun, and an independent grease pump, all mounted on the assembly system. The grease gun is installed at the movable end of the horizontal feed cylinder for advancing the grease gun forward to bring it close to the threaded position of the bolt.

[0018] It also includes a contour simulation system for precision calibration and torque testing before robot operation.

[0019] The contour simulation system includes a simulated component moving base with a torque sensor mounted on it, which performs accuracy calibration and torque testing before the robot operates; the simulated component moving base is a telescopic frame.

[0020] By employing the above technical solution, the present invention has at least the following beneficial effects:

[0021] This invention integrates a gearbox capping and a swaying tightening mechanism into a single structure. The gearbox transmits power to the screw to cap it with a nut. When a high torque output is required for final tightening, the gearbox locks the screw in place, while the entire gearbox rotates to tighten it. This device avoids the limitations imposed by space constraints, small gear size, and inability to output high torque when tightening with a gearbox, and also overcomes the drawback of pure swaying structures being unable to cap the screw.

[0022] This invention improves the consistency of the tightening process and the accuracy of the tightening torque of the connecting bolts of the high-vortex rotor, and increases production efficiency; at the same time, it reduces manual intervention and lowers the intensity of manual labor. Attached Figure Description

[0023] Figure 1 A schematic diagram of the overall structure of the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines provided by the present invention;

[0024] Figure 2 This is a schematic diagram of the assembly system in the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines according to the present invention;

[0025] Figure 3 This is a front view of the assembly system in the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines according to the present invention;

[0026] Figure 4 This is a side view of the assembly system in the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines according to the present invention.

[0027] Figure 5 This is a top view of the assembly system in the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines according to the present invention;

[0028] Figure 6 This is a schematic diagram of the automatic bolt feeding unit of the assembly system in this invention;

[0029] Figure 7 This is a schematic diagram of the tightening part of the assembly system in this invention. Figure 1 (The bolt feeding clamp is conveying bolts in various states).

[0030] Figure 8 This is a schematic diagram of the tightening part of the assembly system in this invention. Figure 2(Bolt loading jaws open and raised);

[0031] Figure 9 A schematic diagram of the workpiece positioning and clamping system of the automatic tightening robot for connecting bolts of high-pressure turbine rotors of aero engines provided by the present invention;

[0032] Figure 10 A schematic diagram of the contour simulation system for the automatic tightening robot for connecting bolts of high-pressure turbine rotors in aero-engines provided by the present invention;

[0033] In the picture:

[0034] 1. Assembly system; 2. Tooling indexing and positioning unit; 3. Tightening central unit; 4. Horizontal synchronous feed unit; 5. Automatic bolt feeding unit; 6. Workpiece positioning and clamping system; 7. Contouring simulation system; 8. Automatic grease application system; 9. Lifting screw mounting plate; 10. Lifting guide rail; 11. Lifting drive motor reducer screw; 12. Left and right mounting plate connecting frame; 13. Lifting guide rail slide; 14. Lifting base plate; 15. Lifting limit stop; 16. Tooling lifting fixture; 17. Horizontal slide; 18. Horizontal drive motor reducer; 19. Drive gear; 20. Short rack; 21. Horizontal guide rail; 22. Indexing drive motor reducer; 23. Indexing drive gear; 24. Indexing gear seat; 25. Indexing fixed gear ring; 26. Indexing rotary table; 27. Turntable bearing; 28. Turntable fixed base plate; 29. ​​Tightening power source; 30. Tightening shaft C-type bearing bracket; 31. L-shaped tightening power swing transmission shaft; 32. Cap recognition transmission gearbox; 33. Tightening sleeve; 34. Cap recognition drive motor reducer; 35. Bolt feeding axial feed cylinder; 36. Bolt feeding gripper cylinder; 37. Bolt feeding gripper; 38. Bolt preparation tray; 39. Preparation tray rotation drive motor; 40. Bolt pushing cylinder action mechanism; 41. Bolt detection photoelectric switch; 42. Glue gun; 43. Glue gun horizontal feed cylinder; 44. 45. Adhesive supply pump; 46. Movable frame with horizontal guide rail; 47. Rotary adjustment base; 48. Screw lifter; 49. Pressure plate; 50. Pressure force sensor; 51. Pressure transition fixture; 51. Simulation component moving base; 51-1. Fixed base; 51-2. Telescopic mounting frame; 51-2-1. Bottom bracket; 51-2-2. Mounting frame; 52. Torque sensor; 53. Endoscope; 54. Fixed support; 55. Feeding base. Detailed Implementation

[0035] To better explain and facilitate understanding of the present invention, the technical solution and effects of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] like Figures 1-10As shown, an automated bolt tightening robot for high-pressure turbine rotor connections in aero-engines includes a contour simulation system 7, a workpiece positioning and clamping system 6, an assembly system 1, and an automated grease application system 8 that work together. The contour simulation system 7 is used for precision calibration and torque testing before robot operation. The workpiece positioning and clamping system 6 is used to position, clamp, and fix the workpiece to be assembled, providing a stable operating reference for the tightening robot. The assembly system 1 is used for automated assembly of the workpiece. The automated grease application system 8 is used for automated grease application to the bolt threads, ensuring lubrication and reliable tightening of the bolt assembly. This invention achieves fully automated operation of bolts from material preparation to tightening through the coordinated work of the workpiece positioning and clamping system 6, the assembly system 1, the automated grease application system 8, and the contour simulation system.

[0037] The contour simulation system 7 includes an independent simulation component moving base 51 and a torque sensor 52. The torque sensor 52 is installed in the frame of the simulation component moving base 51 to test the tightening torque of the tightening robot. The rotor simulation component is installed in the positioning groove on the top of the simulation component moving base 51.

[0038] Specifically, the simulated component moving base 51 includes a fixed base 51-1 and a telescopic mounting frame 51-2 mounted on the fixed base 51-1. A torque sensor 52 is installed within the telescopic mounting frame 51-2. The telescopic mounting frame 51-2 includes a bottom support 51-2-1 and a mounting frame 51-2-2 slidably connected to the bottom support 51-2-1. The mounting frame 51-2-2 includes two opposing semi-circular frames that can move radially along the bottom support 51-2-1 to form a complete circular mounting frame for placing the robot assembly system 1, facilitating precision calibration and torque testing before robot operation. The mounting frame 51-2-2 slides radially on the bottom support 51-2-1, facilitating the installation of the assembly system 1 and adapting to assembly systems 1 of different sizes.

[0039] In the non-working state before formal assembly, the robot's assembly system 1 is placed in the positioning groove on the top of the simulated component moving base 51 of the contour simulation system 7 to test the positioning accuracy of the bolt mounting holes and the accuracy difference between the output torque of the tightening power source 29 and the set value, to ensure that the robot's performance meets the standards before operation.

[0040] The workpiece positioning and clamping system 6 includes a fixed support 54, an independent movable frame 45 with a horizontal guide rail, a rotating adjustment base 46, a screw lifter 47, a clamping plate 48, a clamping force sensor 49, and a clamping transition fixture 50. The independent movable frame 45 with a horizontal guide rail is mounted on the fixed support 54. The rotating adjustment base 46 is slidably connected to the independent movable frame 45 with a horizontal guide rail and cooperates with the horizontal guide rail 21 for accommodating and moving the workpiece to be assembled. The rotating adjustment base 46 includes a sliding base and a workpiece carrier rotatably connected thereto. The sliding base cooperates with the horizontal guide rail 21. The workpiece carrier has a disc-shaped structure and can rotate around its own rotation axis to achieve the rotation of the workpiece to be assembled carried on it. Specifically, the sliding base and the independent movable frame 45 with a horizontal guide rail are connected by a screw drive. The motor drives the screw to rotate, causing the sliding base threaded on the screw to move along the horizontal guide rail 21. Furthermore, the fixed support 54 is semi-enclosed, with one end of the horizontal guide rail 21 corresponding to the opening of the fixed support 54. By rotating the adjusting base 46 and moving it along the horizontal guide rail 21, the workpiece to be assembled can be moved from the opening of the fixed support 54 to the inside of the fixed support 54 for subsequent clamping and further assembly.

[0041] Furthermore, the clamping plate 48 is mounted on the independent movable frame 45 with horizontal guide rails via a screw lifter 47. The independent movable frame 45 with horizontal guide rails has guide rails installed along its height. Driven by the screw lifter 47, the clamping plate 48 moves up and down along its height, thereby longitudinally clamping the workpiece to be assembled. Furthermore, a clamping force sensor 49 is installed on the clamping plate 48 to detect the clamping force in real time, ensuring reliable clamping without damaging the workpiece. To ensure stable and precise clamping of the workpiece to be assembled, a clamping transition fixture 50 is installed on the clamping plate 48, located above the workpiece on the rotating adjustment base 46. The screw lifter 47 drives the clamping plate 48 to descend, and the clamping plate 48 clamps the workpiece through the clamping transition fixture 50. The tightening robot is connected and fixed to the clamping transition fixture 50 via a positioning pin, achieving axis alignment between the robot and the workpiece.

[0042] The clamping transition fixture 50 includes a clamping top plate connected to the clamping plate 48, located near the workpiece to be assembled. The bottom structure of the tightening robot is positioned and connected to the clamping top plate by a pin, and the circumferential torque is transmitted to the clamping transition fixture 50 and the clamping plate 48. The workpiece to be assembled is located between the clamping transition fixture 50 and the rotating adjustment base 46. Since the tightening robot is positioned above the workpiece via a lifting mechanism, it cannot be directly connected and fixed to the workpiece. Therefore, the workpiece itself cannot provide anti-torque support during tightening. Based on this, the clamping transition fixture 50 enables the workpiece body to transmit anti-torque to the clamping plate 48 through the clamping transition fixture 50. The clamping plate 48 and the clamping transition fixture 50 are raised and lowered by screw lifters 47 on both sides. When pressing the workpiece, the clamping force value is determined by the clamping force sensor 49.

[0043] Furthermore, the bottom end face of the clamping top plate is provided with teeth. Before assembly, the high-vortex rotor of the workpiece to be assembled is installed on the rotating adjustment base 46 of the workpiece positioning and clamping system 6. The rotating adjustment base 46 is rotated to adjust the orientation of the workpiece to be assembled. A clamping transition fixture 50 is installed on the top of the workpiece to be assembled, and the teeth on the top shaft end face of the workpiece to be assembled are engaged. After the two are interlocked, the workpiece to be assembled is locked. The lead screw drives the rotating adjustment base 46 and the high-vortex rotor of the workpiece to be assembled on it to move into the fixed support 54 to below the clamping plate 48. The screw jack 47 drives the clamping plate 48 to descend, so that the clamping plate 48 presses the clamping transition fixture 50 from the top. Then the robot is hoisted above the clamping transition fixture 50 and connected and positioned with the clamping transition fixture 50 through the positioning pin. During tightening, the clamping top plate and the teeth of the workpiece to be assembled provide circumferential counter-torsion to ensure the fixation of the workpiece to be assembled.

[0044] The assembly system 1 includes a tooling lifting unit, a horizontal synchronous feed unit 4, a tightening central unit 3, an automatic bolt feeding unit 5, and a tooling indexing and positioning unit 2. Specifically, the tooling lifting unit is used to achieve precise lifting and feeding along the rotor axis. The horizontal synchronous feed unit 4 is mounted on the lifting part of the tooling lifting unit and is used to achieve synchronous reverse movement along the rotor radial direction. Two sets of tightening central units 3 are respectively installed on the horizontal moving part of the horizontal synchronous feed unit 4 and are used to achieve automatic head matching and tightening of the bolt head and tightening sleeve 33. The material preparation part of the automatic bolt feeding unit 5 is installed on the indexing rotation part of the tooling indexing and positioning unit 2, and the feeding jaws are connected to the swing transmission end of the tightening central unit 3 to achieve continuous automated bolt supply. The turntable fixing part of the tooling indexing and positioning unit 2 is connected to the contour simulation system 7 and the workpiece positioning and clamping system 6 in sequence. The tooling indexing and positioning unit 2 is used to complete the bolt hole indexing in the 360° circumferential direction. Each system is connected by a mechanical structure and linked with the CNC system to form a complete operation link. Its core function is to work together to achieve precise three-dimensional positioning of "axial lifting - circumferential indexing - radial feeding", complete the automated feeding, cap recognition, conveying and precise tightening of bolts. It is suitable for the narrow space inside the high vortex rotor and the scenario of multiple bolts distributed circumferentially. It not only ensures the accuracy of bolt tightening torque and assembly consistency, but also greatly improves assembly efficiency and reduces the intensity of manual labor.

[0045] Specifically, the tooling lifting unit is installed on the tooling indexing and positioning unit 2, including two opposing lifting screw mounting plates 9, which are mounted on the indexing rotary disk 26 of the tooling indexing and positioning unit 2. Two drive motor reducer screws 11 are correspondingly mounted on the two lifting screw mounting plates 9, and move synchronously left and right. The lifting guide rail slide 13 is threadedly connected to the drive motor reducer screw 11, and the lifting base plate 14 is connected to the two lifting guide rail slides 13. The lifting drive motor reducer screw 11 provides power for the lifting of the lifting slide 13, and the lifting base plate 14 achieves lifting by driving the two lifting guide rail slides 13 to move synchronously up and down through the drive motor reducer screw 11. A lifting limit block 15 is provided at the top of the lifting screw mounting plate 9 to limit the upward movement of components on the lifting base plate 14. Furthermore, a lifting guide rail 10 is arranged parallel to the drive motor reducer screw 11 on the lifting screw mounting plate 9, and a lifting guide rail slide 13 is sleeved on the lifting guide rail 10 to provide lifting guidance for the lifting guide rail slide 13, so that the lifting slide 13 can move up and down along the lifting guide rail 10 to realize the lifting of the lifting base plate 14.

[0046] The lifting drive motor reducer screw 11 is the power source, which drives the two lifting guide rail slides 13 on both sides to move up and down synchronously along the lifting guide rail 10, thereby driving the middle lifting base plate 14 to achieve lifting action, and finally carrying the tightening central unit 3 and the horizontal synchronous feed unit 4 installed on the lifting base plate 14 to complete the axial feed.

[0047] The horizontal synchronous feed unit 4 has identical left and right structures, specifically including two parallel horizontal slides 17, on which the tightening central unit 3 is mounted. Further, the horizontal slides 17 are connected to the tooling lifting unit via a gear and rack transmission mechanism to achieve horizontal synchronous feed. Specifically, a horizontal drive motor reducer 18 is mounted on each horizontal slide 17, and a drive gear 19 is connected to the output end of the reducer. The drive gear 19 meshes with a short rack 20 mounted on the lifting base plate 14. The horizontal drive motor reducer 18 drives the drive gear 19 to rotate, and the meshing of the drive gear 19 with the short rack 20 achieves the opposite synchronous horizontal movement of the two horizontal slides 17, realizing the radial feed and reset of the tightening central unit 3. Simultaneously, to ensure stable movement of the horizontal slides 17, a horizontal guide rail 21 is arranged parallel to the short rack 20 on the lifting base plate 14 for guiding the movement of the horizontal slides 17.

[0048] The horizontal drive motor reducer 18 meshes with the short rack 20 through the drive gear 19, driving the two horizontal slides 17 to move the tightening central unit 3 on them synchronously in opposite directions along the horizontal guide rail 21, thereby realizing the radial feed and reset of the tightening central system.

[0049] The tightening central unit 3 includes a tightening power source 29, specifically a tightening gun, mounted on the horizontal slide 17. An L-shaped tightening power swing transmission shaft 31 is rotatably connected to the output end of the tightening power source 29. A bearing for connecting the L-shaped tightening power swing transmission shaft 31 to the tightening power source 29 is mounted on a C-shaped bearing bracket 30, which is fixed to the horizontal slide 17. A cap-recognition transmission gearbox 32 is mounted at the end of the L-shaped tightening power swing transmission shaft 31, and a tightening sleeve 33 is mounted at the output end of the cap-recognition transmission gearbox 32 to complete the tightening action. Furthermore, a cap-recognition drive motor reducer 34 drives the input end of the cap-recognition transmission gearbox 32, which serves as the power source for the cap-recognition transmission gearbox 32, thereby transmitting torque to the tightening sleeve 33 at its output end through the cap-recognition transmission gearbox 32.

[0050] To facilitate the cap identification operation, the bottom of the cap identification transmission gearbox 32 is equipped with an endoscope 53 embedded in a guide groove for installation. The endoscope 53 can assist in observing the cap identification and tightening status of bolts in confined spaces.

[0051] The tightening power source 29 provides precise torque output, which is transmitted to the cap-adjusting transmission gearbox 32 via an L-shaped tightening power swing transmission shaft, causing the cap-adjusting transmission gearbox 32 to rotate. The cap-adjusting drive motor reducer 34 drives the cap-adjusting transmission gearbox 32 to rotate the tightening sleeve 33, achieving cap-adjusting adaptation between the bolt head and the tightening sleeve 33. During tightening, the operation is completed by the overall swing of the cap-adjusting transmission gearbox 32 driven by the cap-adjusting drive motor reducer 34. Combined with the support and anti-torsion design formed by the meshing of the clamping transition fixture 50 and the longwall gear at the top shaft end of the workpiece to be assembled, structural deformation is avoided from affecting the tightening accuracy.

[0052] To achieve the assembly and tightening of all bolts in the circumferential direction, the tooling indexing and positioning unit 2 includes an indexing rotary disk 26. An indexing drive gear 23, driven by an indexing drive motor reducer 22, is mounted on the indexing rotary disk 26 and connected and fixed via an indexing gear seat 24. The indexing drive gear 23 meshes with an indexing fixed gear ring 25 located on the inner ring of the turntable fixed base plate 28. The indexing drive motor reducer 22 provides power for the rotary indexing and positioning. A turntable bearing 27 is provided between the turntable fixed base plate 28 and the indexing rotary disk 26 to provide rotational support for the rotational movement of the indexing rotary disk 26.

[0053] The indexing drive motor reducer 22 provides rotational power, driving the indexing drive gear 23 fixed on the indexing rotary table 26 to rotate along the indexing fixed gear ring 25 fixed on the turntable fixed base plate 28. During rotation, the turntable bearing 27 provides stable rotational support for the indexing rotary table 26, and the rotation angle is precisely controlled by the encoder to achieve bolt hole positioning in the 360° circumferential direction.

[0054] To achieve automatic feeding, the automatic bolt feeding unit 5 includes a feeding base 55 mounted on an indexing rotary table 26, and a bolt storage tray 38 mounted on the feeding base 55 and driven by a tray rotation drive motor 39. Bolts to be tightened are circumferentially hung on the edge of the bolt storage tray 38, which has corresponding notches on its side. A bolt-pushing cylinder actuation mechanism 40 is also installed on the feeding base 55. Aligning the bolts with the bolt storage tray 38, the extension action of the bolt-pushing cylinder actuation mechanism 40 pushes one bolt hanging on the bolt storage tray 38 upwards, away from the upper surface of the tray 38. A bolt detection photoelectric switch 41 is installed on the feeding base 55. Furthermore, a gripper is installed on the L-shaped tightening power swing transmission shaft 31 via a bolt feeding axial feed cylinder 35. The gripper is installed on the movable end of the bolt feeding axial feed cylinder 35 and can move longitudinally up and down along the height direction of the L-shaped tightening power swing transmission shaft 31. Driven by the bolt feeding axial feed cylinder 35, the gripper moves to the bottom of the bolt clamping transmission gearbox 32 to clamp the bolt.

[0055] Furthermore, the gripper includes two bolt feeding jaws 37 connected by a bolt feeding jaw cylinder 36. The two bolt feeding jaws 37 are arranged opposite each other for gripping bolts. The extension and retraction direction of the bolt feeding jaw cylinder 36 is horizontal, perpendicular to the extension and retraction direction of the bolt feeding axial feed cylinder 35.

[0056] During loading, the bolt storage tray 38 is driven by a rotary drive motor to rotate stepwise. A bolt detection photoelectric switch 41 continuously monitors the presence of bolts in the tray's holes. When a bolt rotates to the position corresponding to the gripper, a bolt pusher cylinder mechanism 40 pushes the bolt upwards, placing it in the gripping position. The bolt loading gripper 37 opens under the drive of the bolt loading gripper cylinder 36, descends under the drive of the bolt loading axial feed cylinder 35, and closes under the drive of the bolt loading gripper cylinder 36 to grip the bolt in the gripping position. The bolt loading axial feed cylinder 35 then rises, pushing the bolt below the tightening sleeve 33, coordinating with the bolt cap recognition action to complete the bolt handover.

[0057] The bolt storage tray 38 is driven by a rotary drive motor to rotate in one step per bolt. The bolt detection photoelectric switch 41 can detect whether there are spare bolts in the holes on the tray. After the spare bolt is turned to face the axis of the indexing rotary table 26 and aligns with the gripper, the bolt pushing cylinder action mechanism 40 removes the bolt from the half-open hole (notch) of the tray by lifting and then moving it outward. The tooling lifting unit is activated, the lifting base plate 14 rises, and the L-shaped tightening power swing transmission shaft 31 rises to a position higher than the bolt storage tray 38. The bolt loading gripper 37 on the L-shaped tightening power swing transmission shaft 31 is pushed by the bolt loading axial feed cylinder 35 and the bolt loading gripper cylinder 36 to descend to a position lower than the height of the tightening sleeve 33. The horizontal synchronous feed unit 4 is activated, positioning the tightening sleeve 33 directly above the bolt to be gripped. Subsequently, the bolt feeding gripper cylinder 36 closes the bolt feeding gripper 37, clamping the bolt head at its end. The bolt feeding axial feed cylinder 35 then rises, bringing the bolt head closer to the tightening sleeve 33. Simultaneously, the cap-recognition drive motor reducer 34 drives the cap-recognition transmission gearbox 32, rotating the tightening sleeve 33 until the bolt head is screwed into the tightening sleeve 33, successfully recognizing the bolt. The elastic clips inside the tightening sleeve 33 hold the bolt head in place, preventing it from falling. The bolt feeding gripper 37 then opens and rises above the cap-recognition transmission gearbox 32, completing the automatic bolt feeding operation.

[0058] To achieve grease application, the automatic grease application system 8 includes two grease guns 42 mounted on the indexing rotary table 2626, a horizontal feed cylinder 43 for the grease guns, and an independent glue supply pump 44. The grease guns 42 are mounted on the movable end of the horizontal feed cylinder 43 to advance the grease guns 42 forward, bringing them close to the threaded position of the bolt. The glue supply pump 44 provides the grease source to the grease guns 42.

[0059] After the tightening sleeve 33 clamps the bolt head, the automatic grease application system 8 located to the side starts, and the horizontal feed cylinder 43 of the grease gun actuates, pushing the grease gun 42 forward and close to the bolt thread. The cap-recognition drive motor reducer 34 operates, and the cap-recognition transmission gearbox 32 drives the tightening sleeve 33 and the bolt to rotate; at the same time, the tooling lifting unit operates, allowing the bolt thread to rotate and rise simultaneously at the nozzle of the grease gun 42. The glue supply pump 44 starts, applying grease to the bolt thread through the grease gun 42. After application, the grease gun 42 retracts, the horizontal synchronous feed unit 4 starts, and the two horizontal slides 17 move towards each other, forming a back-to-back structure, ready to enter the rotor cavity, thus completing the automatic grease application process.

[0060] After the automatic grease application is completed, the tooling lifting unit is activated, and the drive motor reducer screw 11 rotates, causing the lifting guide slide 13 to move downwards. This allows the cap-recognition transmission gearbox 32 to pass through the indexing rotary disk 26 and the high-vortex rotor center hole into the rotor cavity, completing the downward movement of the tightening central unit 3 along the rotor's central axis. The indexing drive motor drives the indexing drive gear 23 to rotate, causing the indexing rotary disk 26 to rotate around the indexing fixed gear ring 25. Based on the encoder recording the first bolt hole position data, the tightening sleeve 33 rotates to that direction. The horizontal synchronous feed unit 4 is activated, and the two horizontal slides 17 move radially outwards along the rotor until the tightening sleeve 33 is directly above the bolt hole position. With the assistance of the endoscope 53, combined with the downward feed and the rotation of the cap-recognition transmission gearbox 32 and the tightening sleeve 33, the bolt is screwed into the hole, completing the automatic positioning and screwing of the bolt.

[0061] In the aforementioned automatic bolt tightening robot for connecting high-pressure turbine rotors of aero-engines, both rotary operation and linear motion are controlled by photoelectric switches. Meanwhile, the contour simulation system 7, workpiece positioning and clamping system 6, assembly system 1, and automatic grease application system 8 are all electrically connected to the control system. All electric cylinders, motors, and reducers have built-in encoders, specifically absolute encoders, which are electrically connected to the control system to form a closed-loop position detection and control adjustment.

[0062] In order to achieve the overall lifting of the robot, the lifting screw mounting plate is equipped with left and right mounting plate connecting frames 12, and tooling lifting fixtures 16 are provided on the left and right mounting plate connecting frames 12.

[0063] The working principle and process of the above-mentioned automatic tightening robot for connecting bolts of high-pressure turbine rotors in aero engines are as follows:

[0064] All electrical components are returned to their initial positions: the lifting base plate 14 is raised to its highest zero position, both horizontal slides 17 move towards each other to their innermost zero positions, the tooling indexing and positioning unit 2 rotates to the preset 0° position, and the tightening power source 29 outputs a zero position with no deflection. All zero points are detected by the motor's encoder, and the control system performs subsequent operations after receiving feedback of all zero-point signals.

[0065] Tightening output torque test: In the non-working state before formal assembly, the robot's assembly system 1 is placed in the positioning groove on the top of the simulated component moving base 51 of the contour simulation system 7. The positioning accuracy of the bolt mounting hole and the accuracy difference between the output torque of the tightening power source 29 and the set value are tested to ensure that the robot's performance meets the standards before operation.

[0066] High-vortex rotor workpiece pre-assembly and robot axis alignment: The high-vortex rotor of the workpiece to be assembled is installed on the rotating adjustment base 46 of the workpiece positioning and clamping system 6. The rotating adjustment base 46 is rotated to adjust the orientation of the workpiece to be assembled. The clamping transition fixture 50 is installed on top of the workpiece to be assembled. After aligning the gear teeth, the workpiece to be assembled and the clamping transition fixture 50 are locked together. The lead screw drives the rotating adjustment base 46 and the high-vortex rotor of the workpiece to be assembled on it to move into the fixed support 54 to below the clamping plate 48. The screw jack 47 drives the clamping plate 48 to descend, so that the clamping plate 48 presses the clamping transition fixture 50 from the top. Then the robot is hoisted above the clamping transition fixture 50 and connected and positioned with the clamping transition fixture 50 through the positioning pin.

[0067] Automatic bolt feeding: The bolt storage tray 38 is driven by a rotary drive motor to rotate in one step per bolt. The bolt detection photoelectric switch 41 can detect whether there are spare bolts in the holes on the tray. After the spare bolt is turned to face the axis of the indexing rotary table 26 and aligns with the gripper, the bolt pushing cylinder action mechanism 40 removes the bolt from the half-open hole (notch) of the tray by lifting and then moving it outward. The tooling lifting unit is activated, the lifting base plate 14 rises, and the L-shaped tightening power swing transmission shaft 31 rises to a position higher than the bolt storage tray 38. The bolt feeding gripper 37 on the L-shaped tightening power swing transmission shaft 31 is pushed by the bolt feeding axial feed cylinder 35 and the bolt feeding gripper cylinder 36 to a position lower than the height of the tightening sleeve 33. The horizontal synchronous feed unit 4 is activated, positioning the tightening sleeve 33 directly above the bolt to be gripped. Subsequently, the bolt feeding gripper cylinder 36 closes the bolt feeding gripper 37, clamping the bolt head at its end. The bolt feeding axial feed cylinder 35 then rises, bringing the bolt head closer to the tightening sleeve 33. Simultaneously, the cap-recognition drive motor reducer 34 drives the cap-recognition transmission gearbox 32, rotating the tightening sleeve 33 until the bolt head is screwed into the tightening sleeve 33, successfully recognizing the bolt. The elastic clips inside the tightening sleeve 33 hold the bolt head in place, preventing it from falling. The bolt feeding gripper 37 then opens and rises above the cap-recognition transmission gearbox 32, completing the automatic bolt feeding operation.

[0068] Automatic grease application: After the tightening sleeve 33 clamps the bolt head, the automatic grease application system 8 located to the side starts, and the horizontal feed cylinder 43 of the grease gun actuates, pushing the grease gun 42 forward and close to the bolt thread. The cap-recognition drive motor reducer 34 works, and the cap-recognition transmission gearbox 32 drives the tightening sleeve 33 and the bolt to rotate; at the same time, the tooling lifting unit operates, allowing the bolt thread to rotate and rise simultaneously at the nozzle of the grease gun 42. The glue supply pump 44 starts, applying grease to the bolt thread through the grease gun 42. After application, the grease gun 42 retracts, the horizontal synchronous feed unit 4 starts, and the two horizontal slides 17 move towards each other, forming a back-to-back structure, ready to enter the rotor cavity, thus completing the automatic grease application process.

[0069] Automatic bolt positioning and screwing: The tooling lifting unit is activated, driving the drive motor reducer screw 11 to rotate, causing the lifting guide slide 13 to move downwards. This allows the cap-recognition transmission gearbox 32 to pass through the indexing rotary disk 26 and the high-vortex rotor center hole into the rotor cavity, completing the downward movement of the tightening pivot unit 3 along the rotor's central axis. The indexing drive motor drives the indexing drive gear 23 to rotate, causing the indexing rotary disk 26 to rotate around the indexing fixed gear ring 25. Based on the encoder recording the first bolt hole position data, the tightening sleeve 33 rotates to that direction. The horizontal synchronous feed unit 4 is activated, and the two horizontal slides 17 move radially outwards along the rotor until the tightening sleeve 33 is directly above the bolt hole position. With the assistance of the endoscope 53, combined with the downward feed and the rotation of the cap-recognition transmission gearbox 32 and the tightening sleeve 33, the bolt is screwed into the hole, completing the automatic bolt positioning and screwing.

[0070] Tightening Operation: When the bolt is screwed into the bottom of the hole and tightening torque is required, the cap-recognition drive motor reducer 34 switches to a brake-locked state, preventing the cap-recognition transmission gearbox 32 and the tightening sleeve 33 from rotating. The tightening power source 29 increases the output torque, causing the tightening shaft C-type bearing bracket 30, L-type tightening power swing transmission shaft 31, cap-recognition transmission gearbox 32, and tightening sleeve 33 to perform repeated swing arm tightening actions as a whole, gradually tightening the bolt. When the torque value detected by the torque sensor integrated in the tightening power source 29 reaches the process set value, the bolt is considered to be successfully tightened, and one tightening process is completed. The tooling lifting unit starts to rise, separating the tightening sleeve 33 from the bolt head, and the L-type tightening power swing transmission shaft 31 of the tightening central unit 3 rotates back to the intermediate zero position. The horizontal synchronous feed unit 4 starts, and the two horizontal slides 17 move towards each other to the innermost back-to-back position, preparing to withdraw from the rotor cavity.

[0071] Tighten the next bolt: Slowly rise and tighten the central unit 3 and withdraw it from the inner cavity of the high-vortex rotor to complete the aforementioned automatic bolt feeding action to replenish bolt supplies. The indexing drive motor reducer 22 provides rotational power, driving the indexing drive gear 23 fixed on the indexing rotary table 26 to rotate along the indexing fixed gear ring 25 fixed on the turntable fixed base plate 28. Continue to repeat the aforementioned automatic bolt positioning, screwing in, and tightening operation procedure until all bolts are tightened.

[0072] Tightening operation complete: The control system resets the electrical components to zero. After the control system completes its self-check and zeroing process, if it is necessary to continue tightening the next set of high-vortex rotor workpieces, there is no need to separate the robot from the clamping plate 48. Simply lift the clamping plate 48 to separate it from the tightened high-vortex rotor workpiece, remove it from under the clamping plate 48, and replace it with a new high-vortex rotor workpiece to continue the automatic tightening operation. If there is no further work, the tightening robot can be lifted as a whole, separated from the clamping plate 48, and placed back on the contour simulation part.

Claims

1. An automatic tightening robot for a high pressure turbine rotor connecting bolt of an aeroengine, characterized in that, include: The workpiece positioning and clamping system positions, clamps, and fixes the workpiece to be assembled, providing a stable operating reference for the tightening robot; An assembly system for moving, positioning, and tightening the working end of the assembly; The assembly system includes a circumferential indexing assembly and an axial feed assembly mounted on the circumferential indexing assembly. A radial synchronous feed assembly is mounted on the axial feed assembly. Specifically, the radial synchronous feed assembly is set on the axial feed assembly through a transmission mechanism and synchronously feeds in the opposite direction through the transmission mechanism. A tightening assembly is set at the end of the radial synchronous feed assembly to realize the three-dimensional movement and tightening of the tightening end. The axial feed assembly, circumferential indexing assembly, and radial synchronous feed assembly all have built-in encoders. Rotary and linear motions are controlled by photoelectric switches to form a closed-loop detection, achieving precise alignment between the tightening end and the bolt hole. An automatic grease coating system applies grease to the threads before bolt assembly.

2. The automatic tightening robot for the connecting bolt of the high pressure turbine rotor of an aero-engine according to claim 1, characterized in that: The workpiece positioning and clamping system includes a fixed support and a workpiece bearing part installed on the fixed support. The workpiece bearing part can slide and rotate along the fixed support. The clamping plate can be raised and lowered and connected to the fixed support for clamping from the top of the workpiece.

3. The automatic tightening robot for the connecting bolt of the high pressure turbine rotor of an aero-engine according to claim 1, characterized in that: The radial synchronous feed assembly includes two sets of tightening assemblies with identical structures.

4. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 1, characterized in that: The tightening assembly includes a tightening power source, a cap-recognition transmission assembly connected to the output end of the tightening power source via a swing transmission assembly, and a tightening sleeve installed at the output end of the cap-recognition transmission assembly. The swing transmission assembly adopts an L-shaped force transmission structure to transmit torque to the tightening sleeve via the cap-recognition transmission assembly. During tightening, the tightening power source drives the cap-recognition transmission assembly and the swing transmission assembly to swing as a whole to complete the torque transmission.

5. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 4, characterized in that: The tightening assembly is equipped with an endoscope embedding and guiding structure at its end for installing an endoscope to assist in observing the bolt cap and tightening status in a narrow space.

6. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 4, characterized in that: The assembly system also includes an automatic bolt feeding assembly, comprising a fixing part mounted on the circumferential indexing assembly, a stocking tray mounted on the fixing part, bolts being hung circumferentially on the edge of the bolt stocking tray, the edge having a corresponding semi-opening; a line pushing assembly corresponding to the bottom of the bolts, pushing the bolts upwards from the stocking tray away from the stocking tray for feeding; a gripping assembly is provided on the swing transmission assembly, the gripping assembly being moved to the bolts away from the stocking tray by the linkage of the circumferential feed cylinder and the horizontal cylinder, clamping and gripping the bolts and conveying them to the tightening sleeve to complete the cap recognition.

7. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 1, characterized in that: The automatic grease application system includes a grease gun, a horizontal feed cylinder for the grease gun, and an independent grease pump, all mounted on the assembly system. The grease gun is installed at the movable end of the horizontal feed cylinder for advancing the grease gun forward to bring it close to the threaded position of the bolt.

8. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 1, characterized in that: It also includes a contour simulation system for precision calibration and torque testing before robot operation.

9. The automatic tightening robot for connecting bolts of a high-pressure turbine rotor of an aero-engine according to claim 8, characterized in that: The contour simulation system includes a simulated component moving base with a torque sensor mounted on it, which performs accuracy calibration and torque testing before the robot operates; the simulated component moving base is a telescopic frame.

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