Aircraft engine pylon and method of changing

Abstract

This invention provides an aircraft engine pylon template and its replacement method based on digital measurement and scanning. Support frame assemblies are symmetrically fixed to the top two sides of the bottom frame assembly, and a crossbeam assembly is fixed to the top of the support frame assemblies. An end frame positioning assembly is fixed to one end of the bottom frame assembly, and tie rod assemblies are arranged on both sides of the end frame positioning assembly. A middle frame positioning assembly is fixed to the top of the bottom frame assembly. Front suspension joint positioning assemblies are symmetrically arranged at the inner bottom end of the crossbeam assembly, and mounting bracket positioning assemblies are arranged between the front suspension joint positioning assemblies. Rear suspension joint positioning assemblies are symmetrically arranged on one side of the inner bottom end of the crossbeam assembly. This template uses a combination of theoretical and physical positioning. The template is coarsely adjusted using the theoretical coordinate values ​​of the design digital model, and finely adjusted using the physical positioning of the pylon product. This effectively eliminates accumulated errors during scanning modeling, parts manufacturing, and final assembly and debugging, improving the overall positioning accuracy of the template.

Description

Technical Field

[0001] This invention relates to the field of aviation maintenance tooling technology, specifically to an aircraft engine mount bracket for aircraft mount joint replacement, repair, and shape-maintaining positioning. Background Technology

[0002] The replacement and deep repair of aircraft engine pylon joints is an essential equipment maintenance project. This process requires designing a suitable jig for the positioning and installation of the engine pylons. A key challenge in jig design is the high precision required for positioning. The spatial positioning accuracy of the eight relevant mounting points on both the upper and lower sides of the engine pylon must not exceed 0.1mm; otherwise, the replacement joints will be unusable. Furthermore, deformation of the jig or loosening or misalignment of positioning components during use will directly affect its positioning accuracy.

[0003] Currently, the conventional jig design and manufacturing process generally uses digital quantity transfer throughout the entire process, and the jig is debugged based on the theoretical positioning of the design digital model. During the scanning modeling, parts manufacturing and final assembly debugging processes, certain cumulative errors will occur, which will affect the overall accuracy of the jig to a certain extent. This will in turn affect the installation accuracy during the subsequent engine mount joint maintenance process, and affect the secondary installation on the aircraft after the maintenance of the aircraft mount. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an aircraft engine pylon template and replacement method based on digital measurement and scanning. This template combines theoretical and physical positioning. The template is coarsely adjusted using the theoretical coordinate values ​​of a digital model, and finely adjusted using the physical positioning of the pylon product. This effectively eliminates accumulated errors during scanning modeling, parts manufacturing, and final assembly, improving the overall positioning accuracy of the template. After the template is finely adjusted, a laser tracker measures the spatial three-dimensional coordinate values ​​of each positioning component. Based on this measured data, the template's status can be monitored in real time during product repair to prevent deformation and misalignment. This template and method achieve one-time qualified installation of the repaired product, solving the problem of high-precision positioning and reassembly for pylon joint repair and replacement. It can be widely applied in similar repair projects.

[0005] To achieve the aforementioned technical features, the present invention aims to provide an aircraft engine pylon bracket based on digital measurement scanning, comprising a base frame assembly, support frame assemblies symmetrically fixed on both sides of the top of the base frame assembly, and a crossbeam assembly fixed on the top of the support frame assembly; an end frame positioning assembly fixed at one end of the base frame assembly, and tie rod assemblies arranged on both sides of the end frame positioning assembly; a middle frame positioning assembly fixed on the top of the base frame assembly; front suspension joint positioning assemblies symmetrically arranged at the inner bottom end of the crossbeam assembly, mounting bracket positioning assemblies arranged between the front suspension joint positioning assemblies, and a rear suspension joint positioning assembly symmetrically arranged on one side of the inner bottom end of the crossbeam assembly.

[0006] Preferably, the bottom frame assembly includes a bottom frame skeleton, with base plates at the four bottom corners of the bottom frame skeleton, connecting plates for mounting support frame assemblies fixed at the four top corners of the bottom frame skeleton, a central mounting seat for mounting a central frame positioning assembly provided in the middle of the bottom frame skeleton, a first mounting plate for mounting an end frame positioning assembly fixed on one side of the top of the bottom frame skeleton, and second mounting plates fixed on both sides of the first mounting plate.

[0007] Preferably, the support frame assembly includes a support frame skeleton, and two reference seats for laser tracker measurement are fixed on the two outer walls of the support frame skeleton.

[0008] Preferably, the crossbeam assembly includes a crossbeam frame, with a first top mounting seat fixed to the inner bottom end of the crossbeam frame for installing the front suspension joint positioning assembly and the mounting bracket positioning assembly, and a second top mounting seat fixed to one side of the inner bottom end of the crossbeam frame for installing the rear suspension joint positioning assembly.

[0009] Preferably, the end frame positioning assembly includes a first pad block disposed on the top of the first mounting plate, an end frame positioning seat fixed on the top of the first pad block, a positioning shaft hole seat disposed at the center of the end frame positioning seat, the positioning shaft hole seat being used to cooperate with the positioning shaft of the aircraft pylon, a plurality of through first laser measuring holes being machined on the positioning shaft hole seat, a first limit pin being symmetrically disposed on the end frame positioning seat, and a plurality of first leveling screws being installed on the end frame positioning seat.

[0010] Preferably, the pull rod assembly includes a positive and negative threaded locking sleeve, with screws installed at both ends of the positive and negative threaded locking sleeve, a U-shaped hinge joint fixed at the end of the screw, a plate rod installed in the middle part of the positive and negative threaded locking sleeve, the U-shaped hinge joint at the bottom end being hinged to the first lug at the top of the second mounting plate via a pin, and the U-shaped hinge joint at the top end being hinged to the hanger lug of the aircraft hanger via a pin.

[0011] Preferably, the middle frame positioning assembly includes a second pad block disposed on the top of the middle mounting base, a middle frame positioning seat fixed on the top of the second pad block, a transverse positioning pin hinged to the top of the middle frame positioning seat via a pin seat, the transverse positioning pin passing through a pin sleeve at the bottom of the aircraft pylon; a second laser measuring hole is machined in the center of the transverse positioning pin, multiple sets of first positioning pins and second leveling screws are provided on the middle frame positioning seat, and a third laser measuring hole is machined on the middle frame positioning seat.

[0012] Preferably, the front suspension connector positioning assembly and the rear suspension connector positioning assembly adopt the same structure and are respectively connected to the front suspension connector and the rear suspension connector on the top of the aircraft pylon. The front suspension connector positioning assembly includes a third pad block disposed at the bottom end of the first top mounting base. A suspension connector seat is fixed at the bottom end of the third pad block. A third leveling screw is disposed on the suspension connector seat. A second ear seat is fixed on the suspension connector seat by a first threaded pin arranged diagonally. A plurality of through fourth laser measuring holes are machined on the second ear seat. A first connecting pin for engaging with the front suspension connector is installed at the bottom end of the second ear seat. A diagonally arranged tapered positioning pin is disposed between the inner suspension connector seat and the second ear seat. A fifth laser measuring hole is machined at the center of the first connecting pin.

[0013] Preferably, the mounting bracket positioning assembly includes a fourth pad block disposed at the middle of the bottom end of the first top mounting base, a mounting bracket positioning seat fixed at the bottom end of the fourth pad block, a fourth leveling screw disposed on the mounting bracket positioning seat, a third ear seat fixed on the mounting bracket positioning seat by second threaded pins arranged diagonally, a first positioning pin fixed at the bottom end of the third ear seat, and a sixth laser measuring hole machined on the third ear seat.

[0014] Another aspect of the present invention provides a method for replacing aircraft pylons, the method employing the aforementioned aircraft engine pylon template based on digital measurement scanning, and includes the following steps: S1, 3D scanning and reverse modeling: Perform 3D scanning and reverse modeling on the aircraft pylon to obtain the theoretical numerical model of the aircraft pylon; at the same time, use a laser tracker to collect the original spatial coordinate data of the suspension joints and the pylon body on the aircraft pylon. S2, Frame positioning, leveling and coarse adjustment: Fix the bottom frame assembly to the work site and level it. Based on the theoretical model, perform overall coarse adjustment of the aircraft rack frame. S3, Aircraft pylon mounting and fixing: The aircraft pylon is hoisted onto the frame, first fixed by the middle frame positioning component, then fixed by the end frame positioning component, and then locked with the tie rod component to prevent the aircraft pylon from pitching due to the shift of the center of gravity. S4, Physical fine-tuning and benchmark locking: Using the actual aircraft rack as a benchmark, fine-tune the front suspension joint positioning component, the rear suspension joint positioning component, and the mounting bracket positioning component to a matching state. After locking each positioning component, use a laser tracker to collect the three-dimensional coordinates of each positioning component as the original benchmark for subsequent accuracy monitoring. S5, stress-free disassembly, replacement and riveting: stress-free disassembly of faulty suspension joints on aircraft racks, replacement of new joints with in-situ riveting, monitoring rack accuracy and positioning status throughout the process, ensuring that all positioning components are free from loosening and jamming. S6, Post-repair re-measurement and comparison: When the replacement and riveting are completed and the aircraft rack is not removed, re-measure the coordinates of each positioning point and compare them with the original benchmark. S7, Final inspection after removal from the rack: After the aircraft rack is removed from the rack, the coordinates of each positioning point are re-measured to confirm that there is no stress release and the coordinate deviation is qualified, and the replacement is completed.

[0015] Beneficial effects of this invention: 1. The present invention employs a combination of theoretical and physical positioning for the mold frame. The mold frame is coarsely adjusted using the theoretical coordinate values ​​of the design digital model, and finely adjusted using the physical positioning of the hanger product. This effectively eliminates accumulated errors during scanning modeling, parts manufacturing, and final assembly, improving the overall positioning accuracy of the mold frame. After the mold frame is finely adjusted, a laser tracker is used to measure the spatial three-dimensional coordinate values ​​of each positioning component. Based on this measured data, the state of the mold frame can be detected and monitored in real time during product repair to prevent deformation and misalignment. This invention achieves one-time qualified installation of the repaired product, solving the problem of high-precision positioning and reassembly for hanger joint repair and replacement, and can be widely applied in similar repair projects.

[0016] 2. This invention solves the problem of high-precision positioning and reassembly for repairing and modifying hanger joints by flexibly converting and applying conventional 3D scanning modeling, frame manufacturing and digital assembly technologies.

[0017] 3. This invention adopts a combination of theoretical positioning and physical positioning. The theoretical coordinate values ​​of the design model are used to coarsely adjust the frame, and the physical positioning of the hanger product is used to finely adjust the frame. This can effectively eliminate the cumulative errors in the scanning modeling, parts manufacturing and final assembly and debugging process, and improve the overall positioning accuracy of the frame.

[0018] 4. After the frame is finely adjusted, the present invention uses a laser tracker to measure the spatial three-dimensional coordinates of each positioning component. Based on this measured data, the status of the frame can be detected and monitored in real time during product repair to prevent deformation and misalignment. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a first-view perspective and a partial three-dimensional view of part A of the present invention.

[0021] Figure 2 This is a three-dimensional view from the second perspective of the present invention.

[0022] Figure 3 For the present invention Figure 2 Partial view of B in the middle.

[0023] Figure 4 This is a three-dimensional view from the third perspective of the present invention.

[0024] Figure 5 For the present invention Figure 4 A partial view in C.

[0025] Figure 6 This is a three-dimensional view from the fourth perspective of the present invention.

[0026] Figure 7 This is a diagram showing the installation of the aircraft pylon of the present invention on the mounting frame.

[0027] Figure 8 This is a first-view 3D view of the aircraft pylon of the present invention.

[0028] Figure 9 This is a second-view 3D diagram of the aircraft pylon of the present invention.

[0029] Figure 10 This is a flowchart of the method of the present invention.

[0030] In the diagram: 1. Bottom frame assembly; 2. Support frame assembly; 3. Crossbeam assembly; 4. End frame positioning assembly; 5. Middle frame positioning assembly; 6. Mounting bracket positioning assembly; 7. Front suspension joint positioning assembly; 8. Tie rod assembly; 9. Rear suspension joint positioning assembly; 10. Aircraft pylon. The base frame 101, base plate 102, second mounting plate 103, middle mounting base 104, connecting plate 105, and first mounting plate 106 are also included. Support frame skeleton 201, reference base 202; 301 crossbeam frame, 302 first top mounting base, 303 second top mounting base; First pad 401, end frame positioning seat 402, first laser measuring hole 403, first leveling screw 404, first limiting pin 405, positioning shaft hole seat 406; Second pad 501, middle frame positioning seat 502, third laser measuring hole 503, first positioning pin 504, second leveling screw 505, second laser measuring hole 506, horizontal positioning pin 507. Fourth pad 601, mounting bracket positioning seat 602, fourth leveling screw 603, second threaded pin 604, third ear seat 605, sixth laser measuring hole 606, first positioning pin 607; First connecting pin 701, fifth laser measuring hole 702, second ear seat 703, fourth laser measuring hole 704, first threaded pin 705, tapered positioning pin 706, third leveling screw 707, suspension connector seat 708, third pad 709. First ear seat 801, U-shaped hinge joint 802, screw 803, positive and negative thread locking sleeve 804, plate rod 805; Front suspension connector 1001, rear suspension connector 1002, positioning shaft 1003, hanger ear plate 1004, pin sleeve 1005. Detailed Implementation

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

[0032] Example 1: See Figure 1-9 A digital measurement and scanning-based aircraft engine pylon frame is disclosed. To establish an overall support and positioning benchmark for the aircraft engine pylon 10, the frame adopts a rigid frame structure, including a base frame assembly 1. Support frame assemblies 2 are symmetrically fixed to the top two sides of the base frame assembly 1, and a crossbeam assembly 3 is fixed to the top of the support frame assembly 2. To achieve end positioning and center-of-gravity stability constraints for the pylon, an end frame positioning assembly 4 is fixed to one end of the base frame assembly 1, and tie rod assemblies 8 are arranged on both sides of the end frame positioning assembly 4. To achieve main positioning of the pylon's center, a center frame positioning assembly 5 is fixed to the top of the base frame assembly 1. To achieve high-precision positioning of multiple joints and mounting brackets at the top of the pylon, front suspension joint positioning assemblies 7 are symmetrically arranged at the inner bottom end of the crossbeam assembly 3, mounting bracket positioning assemblies 6 are arranged between the front suspension joint positioning assemblies 7, and rear suspension joint positioning assemblies 9 are symmetrically arranged on one side of the inner bottom end of the crossbeam assembly 3. This overall structure can form a stable spatial positioning system, providing a rigid benchmark for stress-free pylon replacement and ensuring stable overall positioning accuracy.

[0033] Furthermore, to provide a solid foundation for the overall installation of the frame and ensure reliable ground fixation, the bottom frame assembly 1 includes a bottom frame skeleton 101. Base plates 102 are provided at the four bottom corners of the bottom frame skeleton 101, and connecting plates 105 for mounting the support frame assembly 2 are fixed at the four top corners of the bottom frame skeleton 101. A central mounting seat 104 for mounting the central frame positioning assembly 5 is provided in the middle of the bottom frame skeleton 101. A first mounting plate 106 for mounting the end frame positioning assembly 4 is fixed to one side of the top of the bottom frame skeleton 101, and second mounting plates 103 are fixed to both sides of the first mounting plate 106. The bottom frame assembly undergoes post-weld heat treatment to relieve stress, and each mounting surface is CNC machined to ensure flatness, effectively eliminating welding deformation and providing a high-precision installation reference for the upper assembly.

[0034] Furthermore, to establish a global measurement benchmark for the laser tracker and ensure the rigidity of the vertical support, the support frame assembly 2 includes a support frame skeleton 201, on which two reference seats 202 for laser tracker measurement are fixed respectively. The reference seats 202 serve as fixed reference points for frame accuracy detection. The support frame is stress-relieved and is not easily deformed during long-term use, ensuring a stable and reliable measurement benchmark.

[0035] Furthermore, to provide a mounting carrier for the top positioning components and achieve zoned positioning, the crossbeam assembly 3 includes a crossbeam frame 301. A first top mounting seat 302 for mounting the front suspension connector positioning component 7 and the mounting bracket positioning component 6 is fixed to the inner bottom end of the crossbeam frame 301. A second top mounting seat 303 for mounting the rear suspension connector positioning component 9 is fixed to one side of the inner bottom end of the crossbeam frame 301. The crossbeam assembly has high rigidity and high mounting surface precision, ensuring the coaxiality and positional accuracy of multiple positioning components, meeting the 0.1mm-level positioning requirements.

[0036] Furthermore, to achieve precise positioning of the hanger end and provide laser measurement points, the end frame positioning assembly 4 includes a first pad 401 disposed on the top of the first mounting plate 106. An end frame positioning seat 402 is fixed to the top of the first pad 401. A positioning shaft hole seat 406 is disposed at the center of the end frame positioning seat 402. The positioning shaft hole seat 406 is used to cooperate with the positioning shaft 1003 of the aircraft hanger 10. Multiple sets of through first laser measurement holes 403 are machined on the positioning shaft hole seat 406. First limit pins 405 are symmetrically arranged on the end frame positioning seat 402. Multiple sets of first leveling screws 404 are installed on the end frame positioning seat 402. Fine-tuning of height and attitude can be achieved through the first leveling screws 404. The precise cooperation between the positioning shaft hole seat and the hanger positioning shaft ensures reliable end positioning. The laser measurement holes are used to collect coordinate data.

[0037] Furthermore, to prevent pitching and swaying due to center of gravity shift after the pylon is mounted, the tie rod assembly 8 includes a threaded locking sleeve 804 with screws 803 installed at both ends. A U-shaped hinge joint 802 is fixed to the end of each screw 803. A plate rod 805 is installed in the middle of the threaded locking sleeve 804. The U-shaped hinge joint 802 at the bottom is hinged to the first lug 801 at the top of the second mounting plate 103 via a pin, and the U-shaped hinge joint 802 at the top is hinged to the pylon lug 1004 of the aircraft pylon 10 via a pin. Rotating the plate rod allows for quick adjustment and locking of the tie rod length, achieving stable front-to-back constraint of the pylon. The operation is simple, reliable, and stress-free.

[0038] Furthermore, to achieve the main positioning of the pylon and provide lateral constraint, the central frame positioning assembly 5 includes a second pad 501 disposed on the top of the central mounting base 104. A central frame positioning seat 502 is fixed to the top of the second pad 501. A transverse positioning pin 507 is hinged to the top of the central frame positioning seat 502 via a pin seat. The transverse positioning pin 507 passes through a pin sleeve 1005 at the bottom of the aircraft pylon 10. A second laser measuring hole 506 is machined at the center of the transverse positioning pin 507. Multiple sets of first positioning pins 504 and second leveling screws 505 are provided on the central frame positioning seat 502. A third laser measuring hole 503 is machined on the central frame positioning seat 502. The transverse positioning pin can be flexibly inserted and removed, facilitating rapid mounting and positioning of the pylon. The leveling screws are used for fine-tuning the attitude, and the multiple sets of laser measuring holes ensure comprehensive and accurate coordinate acquisition.

[0039] Furthermore, to achieve detachable and high-precision positioning of the top suspension connector of the pylon, the front suspension connector positioning assembly 7 and the rear suspension connector positioning assembly 9 adopt the same structure and cooperate with the front suspension connector 1001 and the rear suspension connector 1002 on the top of the aircraft pylon 10, respectively. The front suspension connector positioning assembly 7 includes a third pad 709 disposed at the bottom end of the first top mounting base 302. A suspension connector seat 708 is fixed to the bottom end of the third pad 709, and a third leveling screw 70 is disposed on the suspension connector seat 708. 7. A second lug 703 is fixed to the suspension connector seat 708 by a first threaded pin 705 arranged diagonally. Multiple sets of through-hole fourth laser measuring holes 704 are machined on the second lug 703. A first connecting pin 701 for engaging with the front suspension connector 1001 is installed at the bottom of the second lug 703. A diagonally arranged tapered positioning pin 706 is provided between the inner suspension connector seat 708 and the second lug 703. A fifth laser measuring hole 702 is machined at the center of the first connecting pin 701. The threaded pins facilitate quick assembly and disassembly of the lugs, the tapered positioning pins ensure accurate disassembly and reassembly, and the leveling screws allow for fine-tuning of the spatial posture, ensuring a stress-free and jam-free process.

[0040] Furthermore, to achieve precise alignment between the mounting bracket positioning and the connector positioning, the mounting bracket positioning assembly 6 includes a fourth pad 601 located at the middle of the bottom end of the first top mounting base 302. A mounting bracket positioning seat 602 is fixed to the bottom end of the fourth pad 601. A fourth leveling screw 603 is provided on the mounting bracket positioning seat 602. A third ear seat 605 is fixed to the mounting bracket positioning seat 602 via diagonally arranged second threaded pins 604. A first positioning pin 607 is fixed to the bottom end of the third ear seat 605. A sixth laser measuring hole 606 is machined on the third ear seat 605. This assembly structure is consistent with the suspension connector positioning assembly, and is adjustable, detachable, and monitorable, ensuring consistent positioning accuracy between the mounting bracket and the connector.

[0041] Example 2: See Figure 10 In another aspect, the present invention provides a method for replacing aircraft pylons, the method employing the aforementioned aircraft engine pylon template based on digital measurement scanning, comprising the following steps: S1, 3D scanning and reverse modeling: Perform 3D scanning and reverse modeling on the aircraft pylon 10 to obtain the theoretical numerical model of the aircraft pylon; at the same time, use a laser tracker to collect the original spatial coordinate data of the suspension joint and the pylon body on the aircraft pylon 10. S2, Frame positioning, leveling and coarse adjustment: Fix the bottom frame assembly 1 to the work site and level it. Based on the theoretical model, perform overall coarse adjustment of the aircraft rack frame. S3, Aircraft pylon mounting and fixing: The aircraft pylon 10 is hoisted onto the frame, first fixed by the middle frame positioning component 5, then fixed by the end frame positioning component 4, and locked with the tie rod component 8 to prevent the aircraft pylon 10 from pitching due to the shift of the center of gravity. S4, Physical fine-tuning and benchmark locking: Using the aircraft pylon 10 as the benchmark, fine-tune the front suspension joint positioning component 7, the rear suspension joint positioning component 9 and the mounting bracket positioning component 6 to the matching state. After locking each positioning component, use a laser tracker to collect the three-dimensional coordinates of each positioning component as the original benchmark for subsequent accuracy monitoring. S5, stress-free disassembly, replacement and riveting: stress-free disassembly of faulty suspension joints on aircraft racks, replacement of new joints with in-situ riveting, monitoring rack accuracy and positioning status throughout the process, ensuring that all positioning components are free from loosening and jamming. S6, Post-repair re-measurement and comparison: When the replacement and riveting are completed and the aircraft rack 10 is not removed, re-measure the coordinates of each positioning point and compare them with the original benchmark. S7, Final inspection after removal from the rack: After the aircraft rack 10 is removed from the rack, the coordinates of each positioning point are re-measured to confirm that there is no stress release and the coordinate deviation is qualified, and the replacement is completed.

[0042] Working principle of this invention: First, a 3D scan and reverse modeling of the aircraft pylon 10 are performed to obtain a theoretical digital model. Simultaneously, a laser tracker is used to collect the original spatial coordinates of the aircraft pylon 10 and suspension joints 1001 and 1002. The bottom frame assembly 1 is fixed and leveled, and the frame is roughly adjusted based on the theoretical digital model. The aircraft pylon 10 is then hoisted onto the frame, first fixed by the middle frame positioning assembly 5, then fixed by the end frame positioning assembly 4, and secured with the tie rod assembly 8 to balance the center of gravity and prevent pitch. The aircraft... Using the actual pylon 10 as a reference, the front suspension joint positioning component 7, the rear suspension joint positioning component 9, and the mounting bracket positioning component 6 were finely adjusted. After locking, the three-dimensional coordinates of each positioning point were collected as the original reference. The faulty suspension joints 1001 and 1002 were disassembled without stress on the jig, and the new joints were riveted in place to replace them. The accuracy and positioning status of the jig were monitored throughout the process. After the replacement was completed, the coordinates were remeasured before the aircraft pylon 10 was removed from the rack, and then remeasured again after it was removed from the rack. After confirming that there was no stress release and the coordinate deviation was qualified, the replacement was completed.

[0043] Example 3: Based on the process requirements for replacing the suspension joints of aircraft engine mounts, and with the principles of facilitating process operations and ensuring that the engine mount does not deform during the disassembly, replacement, and riveting of the suspension joints, the overall design concept of the engine mount frame is determined as follows: Step 1: A three-dimensional digital model of the aircraft engine pylon is created through three-dimensional scanning and reverse modeling, which serves as a reference for tooling design.

[0044] Step 2: The main frame of the frame is composed of three parts: the base frame, the support frame, and the crossbeam. The frame is made of Q345 square tubes and rectangular tubes welded together. After welding, the materials are subjected to heat treatment to eliminate welding stress.

[0045] Step 3: Based on the actual engine mount, use the 1-frame positioning pin and the 12-frame suspension point as references to limit and fix the engine mount on the frame. Install auxiliary tie rod assembly on the frame to prevent the engine mount from tilting due to instability of the center of gravity when it is mounted.

[0046] Step 4: The four suspension joint positioning seats and mounting bracket positioning seats and the frame mounting plate are CNC machined and have an adjustable structure to facilitate fine-tuning of their spatial posture and position. After they are positioned with the actual product, they are locked and reliably positioned by using positioning pins.

[0047] Step 5: The four suspension connector lugs and mounting bracket positioning seats are all positioned by precision threaded pins, which facilitates easy disassembly and installation of the suspension connectors without causing interference.

[0048] Step 6: Four TB point mounting bases are installed on the frame, which are used as reference points for the laser tracker to collect data. All eight positioning points are equipped with OTP points for the collection and comparative analysis of raw data and post-repair data.

[0049] Engine mount bracket working process: 1. The original data of the four suspension lugs and four suspension joints of the engine mount on the aircraft were collected by a laser tracker and compared and analyzed.

[0050] 2. The engine frame base frame assembly is fixed in the designated position in the factory and leveled. The engine mount is then mounted. First, the 12 frame suspension points are fixed, then the 1 frame positioning pin is fixed, and finally the frame tie rod assembly is used to assist in fixing the engine mount.

[0051] 3. After adjusting the spatial positions of the four suspension joints and mounting bracket positioning seats according to the actual engine mount, fix each positioning component. After fixing, ensure that the positioning pins of each positioning point can rotate flexibly without jamming on site. Then, use a laser tracker to collect the original data of the positioning pins of frame 1, the suspension points of frame 12, the four suspension joints, and the two positioning points of the mounting bracket.

[0052] 4. During the repair process, ensure that the positioning pins at each positioning point can still rotate flexibly without jamming on site, and ensure stress-free assembly throughout the entire repair process.

[0053] 5. After repairs are completed but before the product is removed from the shelves, collect data again and compare it with the original data for analysis. Remove the product from the shelves only after confirming that there are no errors.

[0054] 6. After removal from the assembly line, measure the data of the four suspension joints and the two positioning points of the mounting bracket again and compare them with the original data to ensure that there is no stress during the entire assembly process and no stress release after removal from the assembly line.

Claims

1. An aircraft engine pylon mount based on digital measurement scanning, characterized in that, The assembly includes a bottom frame assembly (1), a support frame assembly (2) symmetrically fixed on both sides of the top of the bottom frame assembly (1), and a crossbeam assembly (3) fixed on the top of the support frame assembly (2); an end frame positioning assembly (4) fixed at one end of the bottom frame assembly (1), and tie rod assemblies (8) provided on both sides of the end frame positioning assembly (4); a middle frame positioning assembly (5) fixed on the top of the bottom frame assembly (1); a front suspension joint positioning assembly (7) symmetrically provided at the inner bottom end of the crossbeam assembly (3), a mounting bracket positioning assembly (6) provided between the front suspension joint positioning assemblies (7), and a rear suspension joint positioning assembly (9) symmetrically provided on one side of the inner bottom end of the crossbeam assembly (3).

2. The aircraft engine pylon type according to claim 1, characterized in that: The bottom frame assembly (1) includes a bottom frame skeleton (101), with a bottom plate (102) at the four bottom corners of the bottom frame skeleton (101), and a connecting plate (105) for mounting the support frame assembly (2) fixed at the four top corners of the bottom frame skeleton (101). A middle mounting seat (104) for mounting the middle frame positioning assembly (5) is provided in the middle of the bottom frame skeleton (101), and a first mounting plate (106) for mounting the end frame positioning assembly (4) is fixed on one side of the top of the bottom frame skeleton (101). Second mounting plates (103) are fixed on both sides of the first mounting plate (106).

3. The aircraft engine pylon type according to claim 2, characterized in that: The support frame assembly (2) includes a support frame skeleton (201), and two reference seats (202) for laser tracker measurement are fixed on the two outer walls of the support frame skeleton (201).

4. The aircraft engine pylon type according to claim 3, characterized in that: The crossbeam assembly (3) includes a crossbeam frame (301), with a first top mounting seat (302) fixed at the inner bottom end of the crossbeam frame (301) for installing the front suspension joint positioning assembly (7) and the mounting bracket positioning assembly (6), and a second top mounting seat (303) fixed on one side of the inner bottom end of the crossbeam frame (301) for installing the rear suspension joint positioning assembly (9).

5. The aircraft engine pylon type according to claim 4, characterized in that: The end frame positioning assembly (4) includes a first pad (401) disposed on the top of the first mounting plate (106), an end frame positioning seat (402) fixed on the top of the first pad (401), a positioning shaft hole seat (406) disposed at the center of the end frame positioning seat (402), the positioning shaft hole seat (406) is used to cooperate with the positioning shaft (1003) of the aircraft rack (10), a plurality of through first laser measuring holes (403) are machined on the positioning shaft hole seat (406), a first limit pin (405) is symmetrically disposed on the end frame positioning seat (402), and a plurality of first leveling screws (404) are installed on the end frame positioning seat (402).

6. The aircraft engine pylon mount based on digital measurement scanning according to claim 4, characterized in that: The pull rod assembly (8) includes a positive and negative threaded locking sleeve (804), with screws (803) installed at both ends of the positive and negative threaded locking sleeve (804), and a U-shaped hinge joint (802) fixed at the end of the screws (803). A plate rod (805) is installed in the middle part of the positive and negative threaded locking sleeve (804). The U-shaped hinge joint (802) at the bottom end is hinged to the first ear seat (801) at the top of the second mounting plate (103) through a pin, and the U-shaped hinge joint (802) at the top end is hinged to the hanger ear plate (1004) of the aircraft hanger (10) through a pin.

7. The aircraft engine pylon type according to claim 4, characterized in that: The middle frame positioning assembly (5) includes a second pad (501) set on the top of the middle mounting base (104), a middle frame positioning seat (502) fixed on the top of the second pad (501), a horizontal positioning pin (507) hinged to the top of the middle frame positioning seat (502) through a pin seat, the horizontal positioning pin (507) passing through the pin sleeve (1005) at the bottom of the aircraft pylon (10); a second laser measuring hole (506) is machined in the center of the horizontal positioning pin (507), multiple sets of first positioning pins (504) and second leveling screws (505) are provided on the middle frame positioning seat (502), and a third laser measuring hole (503) is machined on the middle frame positioning seat (502).

8. The aircraft engine pylon type according to claim 4, characterized in that: The front suspension joint positioning assembly (7) and the rear suspension joint positioning assembly (9) adopt the same structure and are respectively connected to the front suspension joint (1001) and the rear suspension joint (1002) on the top of the aircraft pylon (10). The front suspension joint positioning assembly (7) includes a third pad (709) disposed at the bottom end of the first top mounting seat (302). The bottom end of the third pad (709) is fixed with a suspension joint seat (708). A third leveling screw (707) is disposed on the suspension joint seat (708). The suspension joint seat (708) has a through-hole. A second ear seat (703) is fixed by a first threaded pin (705) arranged diagonally. The second ear seat (703) is machined with multiple sets of through fourth laser measuring holes (704). The bottom end of the second ear seat (703) is fitted with a first connecting pin (701) for cooperating with the front suspension connector (1001). A diagonally arranged tapered positioning pin (706) is provided between the inner suspension connector seat (708) and the second ear seat (703). A fifth laser measuring hole (702) is machined in the center of the first connecting pin (701).

9. The aircraft engine pylon type according to claim 4, characterized in that: The mounting bracket positioning assembly (6) includes a fourth pad (601) located at the middle of the bottom end of the first top mounting base (302). The bottom end of the fourth pad (601) is fixed with a mounting bracket positioning base (602). The mounting bracket positioning base (602) is provided with a fourth leveling screw (603). The mounting bracket positioning base (602) is fixed with a third ear (605) by a second threaded pin (604) arranged diagonally. The bottom end of the third ear (605) is fixed with a first positioning pin (607). The third ear (605) is machined with a sixth laser measuring hole (606).

10. A method for replacing aircraft pylons, characterized in that, The method is implemented using the aircraft engine pylon template based on digital measurement scanning as described in any one of claims 1-9, and includes the following steps: S1, 3D scanning and reverse modeling: 3D scanning and reverse modeling of the aircraft pylon (10) are performed to obtain the theoretical numerical model of the aircraft pylon; at the same time, the original spatial coordinate data of the suspension joint and the pylon body on the aircraft pylon (10) are collected by a laser tracker. S2, Frame positioning, leveling and coarse adjustment: Fix the bottom frame assembly (1) to the work site and level it. Based on the theoretical model, perform overall coarse adjustment of the aircraft rack frame. S3, Fixing the aircraft pylon on the frame: Hoist the aircraft pylon (10) onto the frame, first fix it by limiting it with the middle frame positioning component (5), then fix it by limiting it with the end frame positioning component (4), and use the tie rod component (8) to help lock it to prevent the aircraft pylon (10) from pitching due to the shift of the center of gravity. S4, Physical fine-tuning and benchmark locking: Using the aircraft rack (10) as the benchmark, fine-tune the front suspension joint positioning component (7), the rear suspension joint positioning component (9) and the mounting bracket positioning component (6) to the matching state. After locking each positioning component, use a laser tracker to collect the three-dimensional coordinates of each positioning component as the original benchmark for subsequent accuracy monitoring. S5, stress-free disassembly, replacement and riveting: stress-free disassembly of faulty suspension joints on aircraft racks, replacement of new joints with in-situ riveting, monitoring rack accuracy and positioning status throughout the process, ensuring that all positioning components are free from loosening and jamming. S6, Re-measurement and comparison after repair: When the replacement and riveting are completed and the aircraft rack (10) has not been removed, re-measure the coordinates of each positioning point and compare them with the original reference. S7, Final inspection after removal from the rack: After the aircraft rack (10) is removed from the rack, the coordinates of each positioning point are re-measured to confirm that there is no stress release and the coordinate deviation is qualified, and the replacement is completed.

Images