A drum type inner cavity cantilever high speed rotor balancing tool and balancing method

Abstract

The application discloses a drum type inner cavity cantilever high-speed rotor balancing tool and a balancing method, and belongs to the field of aero-engine assembly. The tool comprises a transmission shaft assembly, a stator casing support assembly, an adapter ring and a bearing seat assembly. The stator casing support assembly is connected and positioned with the bearing seat assembly. The adapter ring is assembled at a front mounting edge of the stator casing support assembly. A front stop of the adapter ring is used for connecting and positioning the stator casing. The transmission shaft assembly is axially and radially clamped and positioned at a stop of a rear mounting edge of a fan disc. The tool solves the balancing problem of a drum type inner cavity cantilever high-speed compressor rotor of a certain type of aero-engine. According to actual production needs and the characteristics of engine components, the balancing tool and the balancing method are provided, and a special balancing tool for the compressor rotor is designed and manufactured by using the tool method.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine assembly, specifically to a drum-type internal cavity cantilever high-speed rotor balancing fixture and balancing method. Background Technology

[0002] In practical engineering, rotors are always unbalanced due to factors such as uneven material composition of rotor components, material defects, processing errors, uneven deformation, wear and tear, and assembly errors.

[0003] For mechanical rotor components, excessive imbalance can easily cause rotor vibration, leading to damage to components such as bearings and shaft seals, reducing the rotor's mechanical life, and increasing the rotor's operational risks. For rotors operating at high safety, high reliability, high precision, and high speeds, such as those used in aero engines, the requirements for imbalance are even more stringent. For rotors with complex structures, the difficulty of achieving balancing is further increased.

[0004] Generally, the mass distribution of the rotor is altered by removing material or adding counterweights, thereby reducing rotor vibration caused by centrifugal force and center-of-mass eccentricity to within the required range, thus ensuring stable engine operation. Rotor balancing typically involves assembling the rotor to be balanced, using balancing fixtures, and connecting a simulated rotor. To ensure accurate and reliable balancing results, the connections and assembly surfaces of the balancing fixtures and the rotor to be balanced must be designed and assembled strictly according to the aero-engine drawings (datum, dimensions, tolerances, etc.) to simulate the engine rotor's operating state as closely as possible.

[0005] The compressor rotor assembly of a certain type of aero-engine is a drum-type internal cavity cantilever structure (such as...). Figure 1 The compressor rotor is mainly composed of a fan disc, a drum, and rotor blades. It is a modular structure, with the external compressor stator consisting primarily of stator blades 40 and a stator casing. The compressor rotor is assembled and connected to other rotors via the rear mounting edges (reference A, reference B) of the fan disc. The stator casing and the engine intermediate casing are fixedly connected via mounting edges.

[0006] After the compressor rotor drum and fan disc are connected, they form an internal cavity structure. The fan disc is then mounted with a side stop to connect with other rotors, forming a cantilever structure. The compressor stator casing and intermediate connecting casing are mounted with side connections, making the internal cavity formed by the drum and fan disc a closed cavity.

[0007] The compressor rotor assembly dynamic balancing simulates the engine assembly structure and operating conditions, and has a high operating speed. Considering the characteristics of the compressor rotor and stator forming a closed internal cavity structure, rotor cantilever connection, small connection area and high installation accuracy at the fan disk rear mounting edge stop, the need for separate connection and fixation of rotor and stator, and the difficulty in transferring the rotor assembly connection reference, coupled with the high requirements for compressor rotor dynamic balancing, the balancing process is very difficult to achieve. Summary of the Invention

[0008] To address the problems existing in the prior art, this invention provides a balancing fixture and method for a drum-type internal cantilever high-speed rotor, solving the balancing problem of a certain type of aero-engine drum-type internal cantilever high-speed compressor rotor (enclosed internal cavity structure of rotor and stator, rotor cantilever connection, small connection area and high installation accuracy of fan disk mounting edge, separate fixing of rotor and stator, difficulty in transferring rotor assembly connection reference, high rotor speed, and strict and high-precision dynamic balancing requirements). Based on actual production needs and the characteristics of engine components, this invention provides a balancing fixture and method, and utilizes the fixture method to design and manufacture a special dynamic balancing fixture for the compressor rotor.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A drum-type internal cavity cantilever high-speed rotor balancing fixture includes a drive shaft assembly, a stator casing support assembly, an adapter ring, and a bearing housing assembly;

[0011] The stator housing support assembly is connected and positioned to the bearing housing assembly; an adapter ring is fitted at the front mounting edge of the stator housing support assembly, and the front stop of the adapter ring is used to connect to the stator housing for positioning.

[0012] The drive shaft assembly is axially and radially positioned and clamped by the rear mounting edge stop on the fan disc; the drive shaft assembly includes a drive shaft, an expansion disc, a pressure cap, a positioning ring, and a drive screw;

[0013] The drive shaft and bearing housing assembly are radially and axially positioned by bearing support and force transmission. The drive shaft is connected to the expansion core plate mounting base through an adapter section. The expansion core plate is mounted on the expansion core plate mounting base, and a positioning ring is mounted on the expansion core plate. The fan plate clamping stop on the expansion core plate and the front end face of the positioning ring clamp the rear mounting edge of the fan plate.

[0014] The pressure cap is installed on the middle shaft head of the expansion core plate mounting base. A pull tube is sleeved on the outer side of the middle shaft head of the expansion core plate mounting base. A pull tube guide groove is opened on the pull tube. A pull tube guide screw is installed in the pull tube guide groove. The pull tube guide screw is used to limit the pull tube circumferentially.

[0015] The front end face of the pull tube is provided with an inner boss structure, and the clamping screw passes through the pressure cover and the middle shaft head of the pull tube connecting the expansion core plate mounting base; the driving screw passes through the middle shaft head of the pull tube connecting the expansion core plate mounting base.

[0016] Preferably, the bearing housing assembly is provided with a rear lifting lug, and the stator housing support assembly is provided with a front lifting lug.

[0017] Preferably, a retaining ring is installed on the outside of the drive screw for limiting, and the retaining ring is fixed to the drive screw by a limiting pin.

[0018] Preferably, the front end of the drive shaft is equipped with a first tapered roller bearing and a second tapered roller bearing; an inner ring spacer and an outer ring spacer are installed between the inner and outer rings of the first tapered roller bearing and the second tapered roller bearing.

[0019] A first bearing cap is installed on the front end of the drive shaft. The first bearing cap has a boss structure that fits and positions with the outer ring of the first tapered roller bearing.

[0020] A nut is installed at the front end of the drive shaft. The nut is tightened through the threaded section to fix the first tapered roller bearing and the second tapered roller bearing in place.

[0021] Preferably, a front bearing connecting platform is installed at the front end of the drive shaft, which is used to connect with the balancing machine support bearing.

[0022] Preferably, a cylindrical roller bearing is installed at the rear end of the drive shaft; a rear bearing connecting platform is installed on the outer side of the cylindrical roller bearing, and the rear bearing connecting platform is used to connect with the balancing machine support bearing.

[0023] The rear end of the bearing housing assembly is equipped with a second bearing cap, and the front end face of the second bearing cap is provided with a boss structure that fits and positions with the outer ring of the cylindrical roller bearing.

[0024] Preferably, a flange is installed at the rear end of the drive shaft, and the flange is connected to the rear end face of the drive shaft by a fifth bolt. The flange is provided with a balancing machine coupling installation interface.

[0025] Preferably, observation holes are evenly distributed on the front end face of the stator casing support assembly.

[0026] Preferably, the assembly end faces of the drive shaft assembly, stator casing support assembly, transition ring, and bearing housing assembly meet the form and position tolerance requirements.

[0027] A method for balancing a drum-type internal cantilever high-speed rotor, based on any one of the above-mentioned drum-type internal cantilever high-speed rotor balancing fixtures, includes the following processes.

[0028] Tighten the drive screw counterclockwise in the reverse direction. The drive screw drives the pull cylinder to slide forward, and the core expansion disc moves forward under tension, causing the fan disc clamping stop to expand and open. At this time, the rear mounting edge of the fan disc is installed and pressed by the pressure cap, so that the rear end face of the rear mounting edge of the fan disc fits and is positioned against the front end face of the positioning ring. Tighten the drive screw clockwise in the reverse direction. The drive screw moves backward, and the deformation state of the core expansion disc gradually recovers. Furthermore, the deformation state of the fan disc clamping stop gradually recovers, thereby clamping the rear mounting edge stop of the fan disc for radial clamping and positioning. When the rear end face of the core expansion disc disengages from the outer protrusion at the rear end of the pull cylinder, the drive screw is no longer under force and can be turned freely, i.e., in a free state. It is considered that the core expansion disc has returned to a free state, i.e., the fan disc clamping stop is in place.

[0029] When the core of the expansion disc is under force, i.e., the drive screw is pulled, the fan disc clamping stop expands and extends, the fan disc is inserted, and it is pressed tightly with the pressure cap; when the core of the expansion disc is not under force, i.e., the drive screw is in a free state, the fan disc clamping stop is in a natural state, clamping the fan disc.

[0030] Compared with the prior art, the present invention has the following beneficial technical effects:

[0031] This invention provides a balancing fixture for a drum-type internal cantilever high-speed rotor. It adjusts the state of the expansion disc using drive screws and tightens the pressure cap using clamping screws, thereby controlling the positioning and clamping of the fan disc's rear mounting edge. This structure offers high positioning accuracy, simple operation, and virtually no difference in operation between different personnel, achieving standardized operation of the balancing fixture. Long-term verification and use have shown that this balancing fixture has good positioning effect and high balancing accuracy, greatly improving the rotor balancing effect. The rotor-stator connection and fixing structure of this invention achieves precise positioning of the compressor rotor-stator assembly, simulating the engine assembly connection state, and completing the outward transfer of the drum-type internal cantilever rotor assembly benchmark. This meets the support conditions and technical requirements of the balancing machine, solving the balancing problem of drum-type internal cantilever high-speed rotors.

[0032] This invention provides a method for balancing high-speed, drum-type internal cavity cantilever rotors. For high-safety, high-reliability, high-precision, and high-speed rotors such as those used in aero-engines, the requirements for imbalance are even more stringent. This invention provides a solution and process method with high positioning accuracy, convenient operation, and good balancing effect for balancing aero-engine rotors, especially complex structures such as internal cavity, cantilever, and high-speed rotors. This balancing fixture and method have significant advantages and scalability. This invention can be applied not only to the balancing of aero-engine rotors but also to the balancing of other types of mechanical rotors. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the compressor rotor structure of a certain type of aero-engine.

[0034] Figure 2 This is a schematic diagram of the compressor rotor balancing fixture structure.

[0035] Figure 3 This is a partially enlarged schematic diagram of position E of the compressor rotor balancing fixture.

[0036] Figure 4 This is a partially enlarged schematic diagram of the position F of the compressor rotor balancing fixture.

[0037] Figure 5 This is a partially enlarged schematic diagram of position G of the compressor rotor balancing fixture.

[0038] Figure 6 This is a partially enlarged schematic diagram of position H of the compressor rotor balancing fixture.

[0039] Figure 7 This is a schematic diagram of the drive shaft assembly of the compressor rotor balancing fixture.

[0040] In the attached diagram: 1 is the rear lifting lug; 2 is the first bolt; 3 is the front lifting lug; 4 is the second bolt; 5 is the transition ring; 6 is the third bolt; 7 is the fourth bolt; 8 is the first bearing cap; 9 is the nut; 10 is the stator casing support assembly; 11 is the front bearing shell connecting platform; 12 is the bearing housing assembly; 13 is the rear bearing shell connecting platform; 14 is the flange; 15 is the fifth bolt; 16 is the sixth bolt; 17 is the second bearing cap; 18 is the cylindrical roller bearing; 19 is the drive shaft; 20 is the first tapered roller bearing; 21 is... 21 is the seventh bolt; 22 is the transition section; 23 is the eighth bolt; 24 is the expansion core plate mounting base; 25 is the expansion core plate; 26 is the positioning ring; 27 is the ninth bolt; 28 is the pressure cap; 29 is the clamping screw; 30 is the drive screw; 31 is the limit pin; 32 is the retaining ring; 33 is the pull cylinder; 34 is the pull cylinder guide screw; 35 is the outer ring spacer; 36 is the inner ring spacer; 37 is the second tapered roller bearing; 38 is the drum; 39 is the stator casing; 40 is the stator blade; 41 is the rotor blade; 42 is the fan disc. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0042] Example

[0043] The present invention provides a drum-type internal cavity cantilever high-speed rotor balancing fixture, comprising a drive shaft assembly, a stator casing support assembly 10, a transition ring 5, a bearing housing assembly 12, etc. (see...) Figure 2 The drive shaft assembly includes a drive shaft 19, an expansion disc 25, a pressure cap 28, a locating ring 26, and a drive screw 30.

[0044] 1) Dynamic balancing process for high-speed, drum-type internal cantilever compressor rotor:

[0045] Rotor-stator connection, fixed and balanced support structure.

[0046] The compressor rotor balancing fixture uses a drive shaft 19 structure for rotor connection. The drive shaft 19 is precisely connected to the rear mounting edge of the fan disc 42 to achieve precise positioning (axial and radial positioning clamping) of the drum-type internal cantilever rotor, thus transmitting the rotor assembly positioning references (reference A, reference B) outwards. The drive shaft 19 and bearing housing assembly 12 are supported and force-transmitting through precision bearings (cylindrical roller bearings, tapered roller bearings) for radial positioning, and axial positioning through the reference positioning end face (reference K). The bearing housing connecting end faces (reference C, reference D) are connected and fixed to the balancing machine bearing bushes, achieving reference transmission with the balancing machine guide rail.

[0047] The compressor rotor balancing fixture uses a stator casing support structure to fix the stator casing 39. The stator casing support assembly 10 is connected and positioned to the bearing housing assembly 12. An adapter ring 5 is installed at the front mounting edge of the stator casing support assembly 10, and the front stop of the adapter ring 5 connects to the stator casing 39 to achieve precise positioning and connection of the stator casing 39. The front stop of the adapter ring 5 meets the positional tolerance requirements of the drive shaft 19 expansion disc 25 and the positioning ring 26 end face, ensuring that the position of the compressor rotor and stator meets the requirements of the drawings.

[0048] The above compressor rotor balancing fixture rotor-stator connection and fixing scheme achieves precise positioning of the compressor rotor-stator assembly, simulates the engine assembly connection state, completes the outward transfer of the drum-type inner cavity cantilever rotor assembly benchmark, and meets the balancing machine support conditions and technical requirements.

[0049] ② Rotor precision positioning assembly structure.

[0050] The compressor rotor operates at a high speed during balancing, and considering its cantilevered internal structure, the requirements for the connection and fixing structure of the balancing fixture are high. During the balancing process, the drive shaft 19 needs to be rotated 180 degrees relative to the compressor rotor to eliminate its own imbalance, which further increases the requirements for the connection and fixing structure of the balancing fixture.

[0051] The balancing tooling drive shaft 19 adjusts the expansion disc 25 structure via the drive screw 30, and the expansion disc 25 positioning stop achieves radial clamping and positioning of the fan disc 42. The positioning ring 26 structure achieves axial positioning of the fan disc 42, and the pressure cap structure achieves axial clamping between the fan disc 42 and the drive shaft 19.

[0052] ③ Rotor dynamic balancing process.

[0053] The compressor rotor has two imbalance correction surfaces, M and N. During dynamic balancing, the rotor imbalance can be adjusted by applying putty to the correction surfaces. The stator casing support assembly 10 has evenly distributed openings on its front end face for applying putty to the correction surface N and for observing the condition of the compressor's internal cavity. During compressor rotor balancing, the initial imbalance must be recorded. The drive shaft 19 is then rotated (180 degrees relative to the compressor rotor) to eliminate any remaining imbalance before final balancing and imbalance correction.

[0054] 2) Functional design of dynamic balancing fixture:

[0055] ① The transmission shaft 19 is precisely connected and positioned (see Figure 3 )

[0056] a. After radially clamping the fan disc 42 using the positioning stop of the expansion disc 25, install the side stop (reference B).

[0057] The expansion disc 25 is fixed to the expansion disc mounting base 24 (precisely centered at the stop) by the ninth bolt 27. The expansion disc mounting base 24 is connected to the drive shaft 19 via the transition section 22. The expansion disc mounting base 24 and the transition section 22 are connected by the eighth bolt 23. The front end of the drive shaft 19 is designed with a first tapered roller bearing 20 and a second tapered roller bearing 37 in a mating configuration. An inner ring spacer 36 and an outer ring spacer 35 are installed between the inner and outer rings of the first tapered roller bearing 20 and the second tapered roller bearing 37. The front end of the drive shaft 19 is designed with a nut 9, which is tightened through the threaded section to fix the mating tapered roller bearings. The rear end of the drive shaft 19 is designed with a cylindrical roller bearing. The flange 14 is connected to the rear end face of the drive shaft 19 by the fifth bolt 15. The flange 14 is designed with a balancing machine coupling mounting interface.

[0058] The expansion core plate 25 has a through hole at its center, through which a pull cylinder 33 passes. The pull cylinder 33 is fitted onto the shaft head in the middle of the expansion core plate mounting base 24, and is precisely slidably fitted with the outer cylindrical surface of the shaft head. The pull cylinder 33 has a guide groove, and a pull cylinder guide screw 34 is designed in the guide groove. The pull cylinder guide screw 34 is tightened to the shaft head in the middle of the expansion core plate mounting base 24. The pull cylinder 33 is limited by the pull cylinder guide screw 34, so that the pull cylinder 33 can only slide axially relative to the shaft head in the middle of the expansion core plate mounting base 24, and cannot rotate circumferentially.

[0059] The front end face of the pull cylinder 33 is designed with an inner boss structure, and the inner boss has evenly distributed through holes. A clamping screw 29 is designed to pass through the through holes and connect to the middle shaft end face of the expansion core plate mounting seat 24, so that the pressure cap 28 is assembled to the outer cylindrical surface of the pull cylinder 33. The middle part of the inner boss structure on the front end face of the pull cylinder 33 has a through hole, and a drive screw 30 passes through the through hole. The tail of the drive screw 30 is designed with a threaded section, which connects to the front end face of the middle shaft head of the expansion core plate 25. The middle part has a boss structure, which is hooked to the rear edge of the inner boss structure on the front end face of the pull cylinder 33. The front end is designed with a retaining ring 32, which is fixed to the drive screw 30 by a limiting pin 31 and hooked to the front edge of the inner boss structure on the front end face of the pull cylinder 33. The drive screw 30 is fixed in its axial relative position with the pull cylinder 33 by its own boss structure and the retaining ring 32. That is, when the drive screw 30 is adjusted, the pull cylinder 33 moves back and forth simultaneously with the drive screw 30.

[0060] The rear end face of the pull cylinder 33 is designed with an external boss structure, which can be hooked to the rear edge of the mounting edge of the through hole of the expansion core plate 25. That is, when the pull cylinder 33 moves forward axially, the external boss structure pulls the expansion core plate 25 forward.

[0061] The front face of the expansion disc 25 is designed with radially evenly distributed slots. When the center of the expansion disc 25 is pulled forward by the outer boss on the rear end face of the pull cylinder 33 (by rotating the drive screw 30 counterclockwise in the counter-clockwise direction, the drive screw 30 moves forward, and at the same time, the pull cylinder 33 is pulled forward), the clamping stop of the fan disc 42 expands and extends (deformed state). When the center of the expansion disc 25 disengages from the outer boss on the rear end face of the pull cylinder 33 (by rotating the drive screw 30 clockwise in the counter-clockwise direction, the drive screw 30 moves backward, and at the same time, the pull cylinder 33 is pulled backward), the center of the expansion disc 25 returns to its initial position (free state), and the clamping stop of the fan disc 42 is in a clamped state, clamping the rear mounting edge stop of the fan disc 42 (reference B), thereby achieving radially precise clamping and positioning of the compressor rotor.

[0062] b. Precise axial positioning is achieved by contacting the front end face of the positioning ring 26 with the rear end face of the fan disc 42 (reference A).

[0063] The positioning ring 26 is fixed to the expansion core plate 25 by the ninth bolt 27 (precision centering of the stop). The front end face is the axial reference surface (reference G). The front end face contacts the rear end face of the rear mounting edge of the fan plate 42 (reference A) to achieve precise axial positioning.

[0064] c. After pressing the fan disc 42 with the pressure cap 28, the front end face of the installation side is installed to achieve precise axial positioning and assembly of the compressor rotor.

[0065] The gland 28 is connected to the central shaft head of the expansion core plate mounting base 24 via clamping screws 29 (which pass through evenly distributed through holes at the inner boss position on the front end face of the pull cylinder 33). The inner cylindrical surface of the gland 28 slides against the outer cylindrical surface of the pull cylinder 33. Tightening the clamping screws 29 causes the rear end face of the gland 28 to mate with the front end face of the rear mounting edge of the fan disc 42. Continuing to tighten the clamping screws 29 causes the gland 28 to slide backward along the cylindrical surface of the pull cylinder 33, simultaneously pushing the fan disc 42 backward until the rear end face of the rear mounting edge of the fan disc 42 mates with the front end face of the positioning ring 26. Tightening the clamping screws 29 axially clamps the fan disc 42, achieving precise axial positioning and assembly of the compressor rotor.

[0066] ②Stator casing support and adapter ring 5 positioning.

[0067] The adapter ring 5 is connected to the stator casing support assembly 10 via the second bolt 4 (centering with a stop); the front end face of the stator casing support assembly 10 is designed with evenly distributed observation holes for applying putty to the correction surface N position and for observing the condition of the compressor cavity; the upper part of the stator casing support assembly 10 is designed with a front lifting lug for lifting the balancing fixture; the rear end face of the stator casing support assembly 10 is connected to the bearing seat assembly 12 via the first bolt 2 (centering with a stop).

[0068] The stator housing 39 is connected to the adapter ring 5 by the third bolt 6. The front mounting side end face of the adapter ring 5 fits with the rear mounting side end face of the stator housing 39 to achieve precise axial positioning, and the centering is achieved by the stop.

[0069] The front stop of the adapter ring 5 and the fan disc 42 at the expansion core of the drive shaft 19 are clamped together. The front end face of the positioning ring 26 meets the position tolerance requirements, ensuring that the position of the compressor stator meets the requirements of the drawing.

[0070] ③Bearing housing structure and bearing bush connection structure.

[0071] The bearing housing assembly 12 is connected to the stator casing support assembly 10 by the seventh bolt 21. The inner cylindrical surface at the front end of the bearing housing assembly 12 mates with the outer ring of the tapered roller bearing mounted on the drive shaft 19, achieving radial positioning of the drive shaft 19. The outer ring of the tapered roller bearing fits against the boss (reference K) on the inner cylindrical surface at the front end of the bearing housing, achieving precise axial positioning of the drive shaft assembly (ensuring the axial dimension Z between the front face of the positioning ring 26 and the end face of the front mounting edge stop of the transition ring 5). The axial clearance of the tapered roller bearing is adjusted by the inner / outer ring spacer to further ensure that the axial dimension Z of the compressor stator meets the design requirements when the rotor is rotating in balance. The front end of the bearing housing assembly 12 is designed with a first bearing cap 8, which is connected to the front end of the bearing housing assembly 12 by the fourth bolt 7. This ensures that the rear end boss of the first bearing cap 8 fits against and is tightly positioned against the outer ring of the tapered roller bearing.

[0072] The bearing housing assembly 12 has a second bearing cap 17 at its rear end. The front end of the second bearing cap 17 has a boss structure that fits and positions itself against the outer ring of the cylindrical roller bearing. The bearing housing assembly 12 has a front bearing bush connecting platform 11 and a rear bearing bush connecting platform 13, which connect to the bearing bush of the balancing machine to achieve balancing fixture (reference C, reference D) and reference transfer with the guide rail of the balancing machine. The rear end of the bearing housing assembly 12 has a rear lifting lug 1 for lifting the balancing fixture. The second bearing cap 17 and the rear bearing bush connecting platform 13 are connected by a sixth bolt 16.

[0073] This invention discloses a method for balancing a high-speed, drum-type internal cantilever rotor, comprising the following steps:

[0074] 1) Study and analyze the assembly drawings of the compressor rotor and stator, and realize the outward transfer of assembly connection datum through balancing tooling to meet the assembly state of the rotor and stator, and meet the support conditions and technical requirements of the balancing machine.

[0075] The front end face of the positioning ring 26 and the clamping stop of the fan disc 42 at the expansion core disc 25 meet the form and position tolerance requirements relative to the bearing housing assembly 12 (C datum, D datum, K datum). The front / rear bearing bush connecting platform of the bearing housing is connected and fixed to the bearing bush of the balancing machine. This realizes the outward transfer and precise positioning of the compressor rotor assembly datum (datum transferred to the balancing machine guide rail).

[0076] The front mounting edge and end face of the adapter ring 5 meet the form and position tolerance requirements relative to the front end face of the positioning ring 26 and the clamping edge of the fan disc 42 at the expansion core disc 25. The front mounting edge end face of the adapter ring 5 meets the distance Z requirement with the front end face of the positioning ring 26, ensuring that the position of the compressor stator meets the requirements of the drawing.

[0077] The balancing fixture's rotor-stator connection and fixing structure enables precise positioning of the compressor rotor-stator assembly, simulates the engine assembly connection state, completes the outward transfer of the drum-type internal cavity cantilever rotor assembly datum, and meets the support conditions and technical requirements of the balancing machine.

[0078] 2) Research and analyze the requirements for the compressor rotor balance correction surface, and combine the characteristics of the compressor rotor drum-type closed inner cavity structure to ensure the bonding of the balance putty and the observation of the balance state of the drum 38 inner cavity.

[0079] The front end face of the stator casing support assembly 10 is designed with evenly distributed observation holes, through which the balancing putty is pasted at point N on the compressor rotor correction surface and the balance status of the inner cavity of the drum 38 can be observed.

[0080] 3) Research and analyze the clamping and positioning requirements of the rear mounting edge of the fan disc 42 to ensure the consistency of the positioning state.

[0081] Tighten the drive screw 30 counterclockwise in the reverse direction. The drive screw 30 drives the pull cylinder 33 to slide forward, and the core of the expansion disc 25 moves forward under tension. The clamping stop of the fan disc 42 expands and extends (deformed state). At this time, the rear mounting edge of the fan disc 42 is installed and pressed by the pressure cap 28, so that the rear end face of the rear mounting edge of the fan disc 42 fits and is positioned against the front end face of the positioning ring 26. Tighten the drive screw 30 clockwise in the reverse direction. The drive screw 30 moves backward, and the deformation state of the core of the expansion disc 25 gradually recovers. Furthermore, the deformation state of the clamping stop of the fan disc 42 gradually recovers, thereby clamping the rear mounting edge stop of the fan disc 42 and achieving precise radial clamping and positioning. When the rear end face of the core of the expansion disc 25 disengages from the rear outer boss of the pull cylinder 33 (at this time, the drive screw 30 is not under force and can be freely turned, i.e., free state), it is considered that the expansion disc 25 has returned to the free state, that is, the clamping stop of the fan disc 42 is clamped in place.

[0082] The expansion disc 25's structural design fully considers the high precision and stringent requirements of compressor rotor balancing, effectively utilizing the characteristic of metal deformation under stress and its return to its original shape when no stress is applied. This allows the fan disc 42's clamping stop to expand and open when the expansion disc 25 is under stress (drive screw 30 is pulled), allowing the fan disc 42 to be inserted and secured by the pressure cap 28. When the expansion disc 25 is not under stress (drive screw 30 is in a free state), the fan disc 42's clamping stop is in its natural state, clamping the fan disc 42. This method ensures consistent and uniform force during each fan disc clamping, guaranteeing the consistency of the fan disc's positioning across multiple clamping operations.

[0083] This invention has achieved its intended purpose. The balancing tooling rotor-stator connection and fixing structure enables precise positioning of the compressor rotor-stator assembly, simulates the engine assembly connection state, completes the outward transfer of the assembly benchmark of the drum-type internal cavity cantilever rotor, meets the support conditions and technical requirements of the balancing machine, and solves the problem of balancing the high-speed rotor of the drum-type internal cavity cantilever.

[0084] The state of the expansion disc 25 is adjusted by the drive screw 30, and the pressure cover 28 is tightened by the clamping screw 29, thereby controlling the positioning and clamping structure of the rear mounting edge of the fan disc. This results in high positioning accuracy, simple operation, and virtually no difference in operation among different personnel, achieving standardized operation of the balancing fixture. After long-term verification and use, this balancing fixture has demonstrated good positioning effect and high balancing accuracy, greatly improving the rotor balancing effect.

[0085] For high-safety, high-reliability, high-precision, and high-speed rotors such as those used in aero-engines, the requirements for imbalance are even more stringent. This invention provides a solution and process method for balancing aero-engine rotors, particularly complex structures such as internal cavity, cantilever, and high-speed rotors, offering high positioning accuracy, convenient operation, and excellent balancing results. This balancing fixture and method have significant advantages and scalability.

[0086] This invention can be applied not only to the field of aircraft engine rotor balancing, but also to the balancing of other types of mechanical rotors.

[0087] This invention relates to a balancing fixture and method designed to solve the balancing problem of a compressor rotor for a certain type of aero-engine. This balancing fixture and method effectively solve the balancing problem of this drum-type internal cantilever high-speed rotor, improving balancing accuracy and achieving standardized balancing operations. After long-term verification and use, the balancing fixture has demonstrated good positioning effect, high balancing accuracy, and significantly improved rotor balancing performance, while also possessing significant technological advantages and scalability.

Claims

1. A drum-type internal cavity cantilever high-speed rotor balancing fixture, characterized in that, Includes drive shaft assembly, stator casing support assembly (10), adapter ring (5), and bearing housing assembly (12); The stator housing support assembly (10) is connected and positioned with the bearing housing assembly (12); a transition ring (5) is installed at the front mounting edge of the stator housing support assembly (10), and the front stop of the transition ring (5) is used to connect the stator housing (39) for positioning. The drive shaft assembly is axially and radially positioned and clamped on the rear mounting edge stop of the fan disc (42); the drive shaft assembly includes a drive shaft (19), an expansion disc (25), a pressure cap (28), a positioning ring (26), and a drive screw (30). The drive shaft (19) and the bearing housing assembly (12) are radially and axially positioned by bearing support and force transmission. The drive shaft (19) is connected to the expansion core plate mounting base (24) through the transition section (22). The expansion core plate (25) is mounted on the expansion core plate mounting base (24). The positioning ring (26) is mounted on the expansion core plate (25). The fan plate clamping stop on the expansion core plate (25) and the front end face of the positioning ring (26) clamp the rear mounting edge of the fan plate. The pressure cap (28) is installed on the middle shaft of the expansion core plate mounting base (24). A pull tube (33) is sleeved on the outer side of the middle shaft of the expansion core plate mounting base (24). A pull tube guide groove is provided on the pull tube (33). A pull tube guide screw (34) is installed in the pull tube guide groove. The pull tube guide screw (34) is used to circumferentially limit the pull tube (33). The front end face of the pull tube (33) is provided with an inner boss structure. The clamping screw (29) passes through the pressure cover (28) and the pull tube (33) and connects to the middle shaft head of the expansion core plate mounting base (24); the driving screw (30) passes through the pull tube (33) and connects to the middle shaft head of the expansion core plate mounting base (24). The front end of the drive shaft (19) is fitted with a first tapered roller bearing (20) and a second tapered roller bearing (37); an inner ring spacer (36) and an outer ring spacer (35) are installed between the inner and outer rings of the first tapered roller bearing (20) and the second tapered roller bearing (37); The first bearing cap (8) is installed on the front end of the drive shaft (19). The first bearing cap (8) is provided with a boss structure, which fits and positions against the outer ring of the first tapered roller bearing (20). The front end of the drive shaft (19) is fitted with a nut (9), which is tightened through the threaded section to fix the first tapered roller bearing (20) and the second tapered roller bearing (37) that are mounted together. A cylindrical roller bearing (18) is installed at the rear end of the drive shaft (19); a rear bearing bush connecting platform (13) is installed on the outside of the cylindrical roller bearing (18), and the rear bearing bush connecting platform (13) is used to connect with the balancing machine support bearing. The bearing housing assembly (12) is equipped with a second bearing cap (17) at its rear end. The front end face of the second bearing cap is provided with a boss structure, which fits and positions against the outer ring of the cylindrical roller bearing (18). A flange (14) is installed at the rear end of the drive shaft (19). The flange (14) is connected to the rear end face of the drive shaft (19) by a fifth bolt (15). A balancing machine coupling installation interface is provided on the flange (14).

2. The drum-type internal cavity cantilever high-speed rotor balancing fixture according to claim 1, characterized in that, The bearing housing assembly (12) is provided with a rear lifting lug (1), and the stator housing support assembly (10) is provided with a front lifting lug (3).

3. The drum-type internal cavity cantilever high-speed rotor balancing fixture according to claim 1, characterized in that, A retaining ring (32) is installed on the outside of the drive screw (30) for limiting the position. The retaining ring (32) is fixed to the drive screw (30) by a limiting pin (31).

4. The drum-type internal cavity cantilever high-speed rotor balancing fixture according to claim 1, characterized in that, The front end of the drive shaft (19) is equipped with a front bearing connecting platform (11), which is used to connect with the balancing machine support bearing.

5. The drum-type internal cavity cantilever high-speed rotor balancing fixture according to claim 1, characterized in that, The front end face of the stator casing support assembly (10) is provided with observation holes.

6. The drum-type internal cavity cantilever high-speed rotor balancing fixture according to claim 1, characterized in that, The assembly end faces of the drive shaft assembly, stator casing support assembly (10), transition ring (5), and bearing seat assembly (12) meet the form and position tolerance requirements.

7. A method for balancing a high-speed rotor with a drum-shaped internal cavity cantilever, characterized in that, A drum-type internal cavity cantilever high-speed rotor balancing fixture according to any one of claims 1 to 6 includes the following processes. Tighten the drive screw (30) counterclockwise in the reverse direction. The drive screw (30) drives the pull cylinder (33) to slide forward. The core of the expansion disc (25) moves forward under tension, and the fan disc clamping stop expands and extends. At this time, the rear mounting edge of the fan disc is installed and pressed by the pressure cap (28), so that the rear end face of the rear mounting edge of the fan disc fits and is positioned against the front end face of the positioning ring. Tighten the drive screw (30) clockwise in the reverse direction. The drive screw (30) moves backward, and the deformation state of the core of the expansion disc (25) gradually recovers. The deformation state of the fan disc clamping stop gradually recovers, thereby clamping the rear mounting edge stop of the fan disc for radial clamping and positioning. When the rear end face of the core of the expansion disc (25) is disengaged from the rear end of the pull cylinder (33), the drive screw (30) is not under force and can be freely turned, i.e., in a free state. It is considered that the expansion disc (25) has recovered to a free state, i.e., the fan disc clamping stop is clamped in place. When the core of the expansion disc (25) is under force, i.e. the drive screw (30) is pulled, the fan disc clamping stop expands and extends, the fan disc is inserted, and the pressure cap is pressed tight; when the core of the expansion disc (25) is not under force, i.e. the drive screw (30) is in a free state, the fan disc clamping stop is in a natural state, and the fan disc is clamped.

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