High-pressure variable geometry turbine guide vane adjusting mechanism and method based on lead screw model

Abstract

The invention provides a high-pressure variable geometry turbine guide vane adjusting mechanism and method based on a lead screw model. The mechanism comprises a gear ring, the gear ring is in sliding connection with an outer casing, the gear ring is meshed with a motor gear, the motor gear is connected with a motor reducer, the gear ring is in threaded connection with a threaded sleeve, and the threaded sleeve penetrates through a set of guide columns. The guide column is fixed in a guide hole in the outer casing and used for guaranteeing that the threaded sleeve does axial movement without radial deflection, the threaded sleeve is connected with one end of a long chain plate through a fixing column body, the other end of the long chain plate is connected with one end of a short chain plate through a short shaft, the other end of the short chain plate is connected with a guide vane shaft of a guide vane, and the guide vane shaft is connected with the guide vane. And the guide vane shaft is arranged between the inner casing and the outer casing. Accurate and stable adjustment of the engine guide vane is achieved, a series of problems in the high-temperature and high-pressure environment in the prior art are effectively solved, the adjustment efficiency and reliability of the engine guide vane are improved, and then the overall performance of an engine is enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-pressure turbines of aero-engines, and particularly relates to a high-pressure variable-geometry turbine guide vane adjusting mechanism and method based on a lead screw model. Background Art

[0002] In the process of engine technology development in recent years, engine adjusting mechanisms in high-temperature and high-pressure environments have shown broad development prospects and application potential. With the continuous improvement of engine performance requirements, higher challenges are posed to the accuracy, reliability, and adaptability of guide vane adjusting mechanisms.

[0003] Existing engine guide vane adjusting mechanisms are difficult to fully meet the complex requirements under high-temperature and high-pressure working conditions in some aspects. For example, there is room for improvement in aspects such as transmission accuracy, friction control, axial and radial motion stability, and the cooperative working efficiency of the overall structure. Therefore, there is an urgent need to design a new high-pressure variable-geometry turbine guide vane adjusting mechanism to better meet the operating requirements of the engine under extreme working conditions and improve the overall performance and working stability of the engine. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-pressure variable-geometry turbine guide vane adjusting mechanism and method based on a lead screw model in order to overcome the above technical problems.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A high-pressure variable-geometry turbine guide vane adjusting mechanism based on a lead screw model, comprising: a tooth ring, the tooth ring is slidably connected to the outer casing, the tooth ring is meshed with a motor gear, the motor gear is connected to a motor reducer, the tooth ring is threadedly connected to a threaded sleeve, the threaded sleeve passes through a group of guide posts, the guide posts are fixed in the guide holes on the outer casing to ensure that the threaded sleeve makes an axial movement without generating radial deflection, the threaded sleeve is connected to one end of a long link plate through a fixed cylinder, the other end of the long link plate is connected to one end of a short link plate through a short shaft, the other end of the short link plate is connected to the guide vane shaft of the guide vane, and the guide vane shaft is installed between the inner casing and the outer casing.

[0007] Further, at least one annular groove is respectively provided on the axial end face of the tooth ring, and a protrusion is provided on the outer casing corresponding to the position of the annular groove, and the protrusion is embedded in the annular groove.

[0008] Further, a ball raceway is provided on the inner wall of the threaded sleeve, balls are installed in the ball raceway, and the balls are in contact with the outer wall of the tooth ring.

[0009] Further, a total temperature and total pressure composite probe is installed on the motor reducer for collecting ambient data and transmitting it to the control system.

[0010] Further, it also includes a control system, and the control system controls the operation of the motor reducer.

[0011] Further, the motor reducer is connected to a high-precision encoder and an intelligent controller.

[0012] Further, an angle sensor is installed on the guide vane shaft to monitor the rotation angle of the guide vane in real time and feed it back to the control system.

[0013] Further, the inside of the tooth ring has a lubrication channel, and the lubrication channel adopts a spiral structure.

[0014] Further, both the motor gear and the tooth ring adopt involute tooth profiles, and the pressure angle is 20°.

[0015] The present invention also includes:

[0016] An adjustment method for the high-pressure variable geometry turbine guide vane adjustment mechanism based on the lead screw model as described above, and this method includes:

[0017] The motor reducer receives the control system instruction, drives the tooth ring to rotate through the motor gear, and the internal thread of the tooth ring meshes with the thread sleeve to convert the rotation into the axial movement of the thread sleeve;

[0018] The thread sleeve axially moves along the guide hole of the outer casing, and the fixed cylinder moves with the thread sleeve, driving the short link plate to rotate around the fixed cylinder.

[0019] The long link plate is connected to the short link plate through a short shaft to convert the axial displacement into the swinging movement of the short link plate, and the short link plate drives the guide vane shaft to rotate to change the guide vane angle.

[0020] The beneficial effect of the present invention lies in:

[0021] The short link plate of the present invention can convert the axial movement of the thread sleeve into the torque adjustment of the guide vane. When the thread sleeve axially moves under the action of power, through the transmission mechanism composed of the short link plate, the short shaft and the long link plate, the force is transmitted to the guide vane, enabling the guide vane to rotate according to the predetermined angle and torque requirements, thereby realizing the precise adjustment of parameters such as the intake or exhaust flow rate and pressure of the engine, and achieving the purpose of optimizing the combustion process and performance of the engine.

[0022] The present invention realizes the precise and stable adjustment of the engine guide vane, effectively solves a series of problems faced by the prior art in high-temperature and high-pressure environments, improves the efficiency and reliability of the engine guide vane adjustment, and further enhances the overall performance of the engine. Description of the Drawings

[0023] Attached Figure 1 is the structural schematic diagram of the present invention.

[0024] Attached Figure 2 is the exploded view of the present invention.

[0025] Attached Figure 3 is the connection schematic diagram of the threaded sleeve and the gear ring of the present invention.

[0026] Attached Figure 4 is the assembly drawing of the gear ring and the motor gear of the present invention.

[0027] Attached Figure 5 is the assembly drawing between the guide vane, the long chain plate, the short shaft and the short chain plate of the present invention.

[0028] In the attached drawings: 1. Inner casing, 1-1. Blade shaft connection hole; 2. Angle sensor; 3. Guide vane, 3-1. Blade shaft; 4. Long chain plate, 4-1. Blade shaft connection hole, 4-2. Short shaft connection hole; 5. Short shaft;

[0029] 6. Short chain plate, 6-1. Short shaft connection hole, 6-2. Short shaft connection hole on the outer side of the gear ring;

[0030] 7. Threaded sleeve, 7-1. First guide hole, 7-2. Internal thread, 7-3. Short shaft on the outer side of the gear ring;

[0031] 8. Slideway;

[0032] 9. Outer casing, 9-1. Guide vane shaft hole, 9-2. Second guide hole;

[0033] 10. Gear ring, 10-1. External teeth of the gear ring, 10-2. External thread;

[0034] 11. Motor gear; 12. Motor reducer; 13. Total temperature and total pressure composite probe. Detailed implementation manners

[0035] The present invention will be further described below with reference to the attached drawings.

[0036] The present invention provides a high-pressure variable geometry turbine guide vane adjusting mechanism based on a lead screw model. As shown in Attachment Figure 1-2 it includes: a gear ring 10, the gear ring 10 is slidably connected to the outer casing 9, the gear ring 10 is meshed with the motor gear 11, the motor gear 11 is connected to the motor reducer 12, the gear ring 10 is threadedly connected to the threaded sleeve 7, the threaded sleeve 7 passes through a set of guide posts 8, and the guide posts 8 are fixed in the second guide hole 9-2 on the outer casing 9 to ensure that the threaded sleeve 7 makes an axial movement without radial deflection. The threaded sleeve 8 is connected to one end of the long chain plate 4 through a fixed column body. The other end of the long chain plate 4 is connected to one end of the short chain plate 6 through a short shaft 5. The other end of the short chain plate 6 is connected to the guide vane shaft 3-1 of the guide vane 3. The guide vane shaft 3-1 is installed between the inner casing 1 and the outer casing 9.

[0037] In this embodiment, at least one annular groove is respectively provided on the axial end faces of the tooth ring 10, and the outer casing 9 has a protrusion corresponding to the position of the annular groove, and the protrusion is embedded in the annular groove.

[0038] As shown in the attached Figure 3 figure, the tooth ring 10 has external teeth 10-1 and external threads 10-2 of the tooth ring.

[0039] The tooth ring 10 and the outer casing 9 are positioned in a sliding friction form.

[0040] Preferably, the tooth ring is made of a high-temperature resistant alloy material, which can withstand the high-temperature environment of an aero-engine. This alloy material contains elements such as chromium (Cr) and cobalt (Co) to ensure high-temperature strength and oxidation resistance. A thermal barrier coating is also provided on the surface of the tooth ring, and the coating thickness is between 0.05-0.2 mm, and the main component contains yttria-stabilized zirconia.

[0041] The surface hardness of the meshing teeth of the tooth ring is not lower than HRC60, and the tooth profile accuracy is between grades 6-8 to ensure good meshing transmission with the motor gear.

[0042] The tooth ring 10 has a lubrication channel inside. The lubrication channel adopts a spiral structure, and the inner diameter of the channel is 3-5 mm. A polytetrafluoroethylene material with high temperature and high pressure resistance and self-lubricating performance is used to make the channel lining. At the entrance of the lubrication channel, a precision flow regulating valve is provided, which can accurately control the flow rate of lubricating oil or grease according to parameters such as the operating conditions of the engine, the rotation speed and load of the tooth ring 10, etc., to ensure that under high temperature and high pressure environment, the lubricating oil or grease is evenly and stably distributed to the contact surfaces of related mating parts such as the tooth ring 10 and the outer casing 9 at a flow rate of 0.1-0.3 milliliters per second, reduce friction and wear, and extend the service life of the parts.

[0043] Both the motor gear 11 and the tooth ring 10 adopt involute tooth profiles, and the pressure angle is 20°.

[0044] When machining the mating surface of the tooth ring 10 and the outer casing 9, a high-precision numerical control machine tool is used to control the surface roughness of the mating surface between Ra0.8-Ra1.6 μm and the cylindricity error within ±0.005 mm to ensure the accuracy of the axial positioning of the tooth ring 10 and reduce the rotational friction force.

[0045] The tooth ring 10 is made of high-strength alloy steel material, such as 42CrMo steel, and after quenching and tempering treatment, the hardness reaches HB280-HB320 to enhance the strength and wear resistance of the tooth ring 10. During the tooth profile machining process of the tooth ring 10, the hobbing process is adopted, and the tooth profile accuracy reaches above grade 6 to ensure the good meshing performance of the combination of the tooth ring 10 and the motor gear 11 and ensure the smooth transmission of circular motion.

[0046] As shown Figure 3 in the figure, the threaded sleeve 7 and the toothed ring are hermetically wrapped and fitted. The hermetic wrapping and fitting of the threaded sleeve 7 and the toothed ring 10 are sealed with a ceramic matrix composite seal, which has good high temperature and high pressure resistance and oil resistance.

[0047] The four slideways 8 on the threaded sleeve 7 are processed by electric discharge machining. The width of the slideway 8 is 3 - 5 mm, the depth is 5 - 8 mm, and the angle between every two slideways 8 is 90° distributed, and the position accuracy is controlled within ±0.1 degrees. The surface of the slideway 8 is chrome-plated, and the thickness of the chrome-plated layer is 0.02 - 0.05 mm, which improves the wear resistance and surface hardness of the slideway 8, ensures that the threaded sleeve 7 will not generate radial deflection during axial movement, so as to ensure that the connecting link plates and guide vanes 3 can move along the predetermined trajectory, and avoid mechanism failures or adjustment errors caused by radial deviations.

[0048] In this embodiment, the inner wall of the threaded sleeve 7 is provided with a ball raceway, balls are installed in the ball raceway, and the balls are in contact with the outer wall of the toothed ring.

[0049] The threaded sleeve 7 has an internal thread 7-2 and a first guide hole 7-2, and the guide post 8 passes through the first guide hole 7-2.

[0050] Preferably, a sealing cover is provided at one end of the threaded sleeve, and a sealing ring is provided between the sealing cover and the threaded sleeve. The sealing ring is a ceramic matrix composite seal, which can withstand the high temperature of the aeroengine to prevent dust and impurities from entering the inside of the threaded sleeve and affecting the ball transmission performance.

[0051] The ball raceway is a groove extending axially and is evenly distributed on the outer periphery of the threaded sleeve. The threaded sleeve is made of a ceramic matrix composite material, which can withstand the high temperature of the aeroengine and has high strength and low expansion coefficient. The balls are made of silicon carbide ceramic material, and the diameter is between 3 - 8 mm.

[0052] As shown Figure 4 in the appendix, in this embodiment, the motor reducer 12 is connected to a high-precision encoder and an intelligent controller, and the motor reducer is connected to the motor.

[0053] Preferably, the motor is a high-temperature resistant motor. Its winding uses special high-temperature resistant electromagnetic wire, and the insulating material can withstand the high temperature of the aeroengine. The motor housing adopts a ceramic fiber and metal composite structure to enhance heat insulation and structural strength. The motor reducer uses high-temperature grease, and the base oil is synthetic ester and is added with high-temperature anti-wear agents such as graphite and molybdenum disulfide.

[0054] The motor reducer adopts a planetary gear reducer, and its reduction ratio is between 10 - 50 to meet the requirements of the guide vane adjustment speed and torque under different working conditions.

[0055] The output shaft of the motor reducer is connected to the motor gear by a spline. The centering accuracy of the spline tooth side is between 0.02 - 0.05 mm to ensure stable torque transmission.

[0056] The gear transmission system inside the motor reducer 12 adopts a helical gear structure. The gear material is 20CrMnTi carburized steel, which is treated by carburizing and quenching, and the tooth surface hardness reaches HRC58 - HRC62.

[0057] The motor reducer 12 is equipped with a high-precision encoder and an intelligent controller. The encoder can monitor the speed and rotation angle of the motor in real time, and the feedback accuracy to the controller reaches ±0.1°. The controller adjusts the transmission ratio of the motor reducer 12 precisely by regulating the input voltage and current of the motor according to the engine working condition requirements, so that the speed output by the motor can be adjusted within the range of 100 - 1000 revolutions per minute, and the torque can be accurately controlled within the range of 10 - 100 N·M to meet the requirements for the adjustment of the guide vane 3 under different working conditions.

[0058] Both the motor gear 11 in the motor gear combination and the gear meshing with it adopt involute tooth profiles, with a module of 2 - 3 and a pressure angle of 20°. The motor gear 11 is made of high-strength aluminum alloy, such as 7075 aluminum alloy, and is treated by anodic oxidation to improve the surface hardness and wear resistance. The meshing gear is made of 45 steel, and the tooth surface is subjected to high-frequency quenching after quenching and tempering, with a hardness reaching HRC45 - HRC50. The motor gear 11 is connected to the motor shaft by an interference fit, and the interference amount is 0.02 - 0.05 mm to ensure the reliability of the connection. The meshing clearance between the motor gear combination and the tooth ring 10 is controlled between 0.1 - 0.3 mm, which is achieved by adjusting the installation position of the gear and using precision gaskets to ensure the smoothness and accuracy of power transmission.

[0059] In this embodiment, the adjustment mechanism of the present invention further includes a control system, which controls the operation of the motor reducer 12. A total temperature and total pressure composite probe 13 is installed on the motor reducer 12 to collect environmental data and transmit it to the control system. The measurement accuracy of the total temperature and total pressure composite probe is within ±0.5%, and the response time does not exceed 10 ms to accurately collect environmental data and promptly feedback it to the control system.

[0060] Preferably, the temperature sensor of the total temperature and total pressure composite probe 13 uses a platinum resistance thermometer, with a measurement accuracy of up to ±0.5°C, capable of accurately measuring the temperature in the engine working environment within a high temperature range of -200°C to 1000°C. The pressure sensor uses a piezoresistive pressure sensor, with a measurement accuracy of ±0.1% FS, and can measure a pressure range of 0 - 10 MPa. The data collected by the sensor is converted into a digital signal through a high-speed A / D converter and transmitted to the control system at a frequency of 100 Hz. The housing of the total temperature and total pressure composite probe 13 is made of stainless steel and is internally encapsulated with heat-insulating materials to ensure the stable operation of the sensor in a high-temperature and high-pressure environment, while having good shielding performance against external electromagnetic interference.

[0061] As shown in the attached Figure 5 In this embodiment, the long link plate 4 is fitted and installed with the fixed cylinder on the threaded sleeve 7. One end of the long link plate 4 is provided with a sleeve hole, which is sleeved on the fixed cylinder and can rotate around it. The long link plate 4 is made of a high-temperature alloy steel plate, with a thickness between 3 - 6 mm, and has undergone a special high-temperature heat treatment process to improve its high-temperature mechanical properties;

[0062] The long link plate 4 is connected to the short link plate through a short shaft 5. Both ends of the short shaft are respectively connected to the long link plate and the short link plate through pins. The short shaft is made of molybdenum Mo alloy to withstand high temperatures and have good toughness. The pins are made of high-temperature alloy materials, with a diameter between 2 - 4 mm. The short shaft and the pins are in interference fit;

[0063] The short link plate 6 moves in cooperation with the guide vane 3. Through the axial movement of the threaded sleeve, the long link plate and the short link plate are driven to move, thereby forming a torque adjustment for the guide vane. One end of the short link plate 6 is connected to the short shaft 5, and the other end is connected to the guide vane shaft 3-1 of the guide vane 3 through a bolt. The short link plate 6 is provided with an arc-shaped groove at the end connected to the guide vane. The arc-shaped groove is adapted to the outer peripheral shape of the guide vane shaft 3-1. The short link plate 6 is made of the same high-temperature alloy steel plate as the long link plate 4. The bolt connecting the short link plate 6 to the guide vane shaft 3-1 is a high-temperature-resistant alloy bolt, with a specification between M6 - M12, and the bolt pre-tightening force is between 10 - 50 N·m. The surface of the bolt is treated with a ceramic coating to enhance its high-temperature corrosion resistance and wear resistance.

[0064] An angle sensor is installed on the guide vane shaft 3-1 to real-time monitor the rotation angle of the guide vane 3 and feedback it to the control system.

[0065] Preferably, the long link plate 4 and the fixed cylinder on the threaded sleeve 7 are rotationally connected through a high-precision deep groove ball bearing. The inner diameter of the deep groove ball bearing and the outer diameter of the fixed cylinder adopt a transition fit, and the fit tolerance is H7 / k6. The outer diameter of the bearing and the mounting hole of the long link plate 4 adopt a clearance fit, and the fit tolerance is H8 / f7, ensuring that it is fixed in position on the short shaft 5 and can rotate, and the rotational frictional resistance is less than 0.1 N·M. The bearing is lubricated with high-temperature resistant grease to prevent impurities from entering the bearing interior and ensure the effective transmission of force and the smoothness of relative movement.

[0066] The short shaft 5 is connected to the short link plate 6 and the long link plate 4 by tapered roller bearings. The short shaft 5 and the long link plate 4 are connected by interference fit, and the interference amount is 0.03 - 0.06 mm, ensuring the fixation of the short shaft 5 on the long link plate 4. The tapered roller bearing is installed in the mounting hole of the short link plate 6. The inner ring of the bearing and the short shaft 5 adopt a clearance fit, and the fit tolerance is H7 / g6. The outer ring and the mounting hole of the short link plate 6 adopt a transition fit, and the fit tolerance is K7 / h6. The tapered roller bearing can withstand large axial and radial forces, will not loosen or get stuck during the torque transmission process, and can adapt to the angular changes and small displacements of the link plate during movement.

[0067] The short link plate 6 and the guide vane 3 are connected by high-strength alloy steel bolts. The bolt specification is M8 - M12, and the strength grade is 10.9. The pre-tightening force of the bolt is controlled by a torque wrench, and the pre-tightening torque is 30 - 50 N·M to ensure the reliability of the connection. Anti-loosening glue is applied to the threads of the bolts to prevent loosening of the connection due to vibration and other factors during the operation of the engine. The short link plate 6 can convert the axial movement of the threaded sleeve 7 into torque adjustment for the guide vane 3. When the threaded sleeve 7 moves axially under the action of power, through the transmission link composed of the short link plate 6, the short shaft 5, and the long link plate 4, the force is transmitted to the guide vane 3, causing the guide vane 3 to rotate according to the predetermined angle and torque requirements, thereby achieving precise adjustment of parameters such as the intake or exhaust flow rate and pressure of the engine, and optimizing the combustion process and performance of the engine.

[0068] The adjustment method of the high-pressure variable geometry turbine guide vane adjustment mechanism based on the lead screw model described in this embodiment includes:

[0069] The motor reducer 12 receives the control system instruction, drives the gear ring 10 to rotate through the motor gear 11, and the internal thread of the gear ring meshes with the threaded sleeve 7, converting the rotation into the axial movement of the threaded sleeve 7;

[0070] The threaded sleeve 7 axially moves along the guide hole of the outer casing 9, and the fixed cylinder moves with the threaded sleeve 7, driving the short link plate to rotate around the fixed cylinder.

[0071] The long link plate 4 is connected to the short link plate 6 through the short shaft 5, converting the axial displacement into the swing motion of the short link plate 6. The short link plate 6 drives the guide vane shaft 3-1 to rotate, changing the angle of the guide vane 3.

[0072] Embodiment 2:

[0073] For the high-pressure variable geometry turbine guide vane adjusting mechanism based on the lead screw model according to Embodiment 1, its assembly process:

[0074] Combined with the attached Figure 1-2 It is described as follows. During the assembly process of the entire engine guide vane adjusting mechanism, first install the gear ring 10 on the outer casing 9 to ensure the fitting accuracy and the smoothness of the lubrication channel. Then install the motor reducer 12, the total temperature and total pressure composite probe 13, and the motor gear combination, and adjust the meshing clearance between the motor gear combination and the gear ring 10. Next, install the threaded sleeve 7 and the fixed cylinder and slideway 8 components connected to the long link plate 4. After that, install the short link plate 6, the short shaft 5, and the long link plate 4, paying attention to the fitting accuracy and lubrication conditions of each connection part. Finally, connect the long link plate 4 to the guide vane 3, check the movement flexibility of the entire mechanism and the connection reliability of each component, and ensure that the engine guide vane adjusting mechanism can operate stably and efficiently under high-temperature and high-pressure environments, meeting the strict requirements for the adjustment of the guide vane 3 under different working conditions of the engine.

[0075] Analysis of the influence of errors on synchronization:

[0076] (1) Influence of the fitting accuracy error between the gear ring and the outer casing: The gear ring and the outer casing are fitted through the annular groove and the protrusion. If the fitting clearance exceeds the tolerance (not between 0.1 - 0.3 mm), the rotational flexibility of the gear ring will be affected, and the axial displacement limit will fail. This will cause the meshing of the motor gear and the gear ring to be unstable, and the power transmission will be uneven, resulting in errors in the guide vane adjustment. For example, the axial movement of the gear ring will cause the change of the meshing point between the motor gear and the gear ring, resulting in torque fluctuations transmitted to the guide vane, affecting the adjustment accuracy of the guide vane angle, destroying the precise control of parameters such as the intake or exhaust flow rate and pressure of the engine, and reducing the performance of the engine.

[0077] (2) Influence of the transmission accuracy error of the motor reducer: If the internal gear transmission system of the motor reducer has insufficient accuracy, such as the gear tooth profile accuracy not meeting the standard or the transmission ratio being unstable, it will lead to inaccurate control of the output speed and torque of the motor. Under different working conditions of the engine, it cannot accurately provide the power required for the guide vane adjustment, resulting in deviation of the guide vane angle adjustment and affecting the optimization of the engine combustion process and performance. For example, the transmission ratio error will cause the output torque of the motor to not match the actual demand, resulting in inaccurate rotation angle of the guide vane.

[0078] (3) Influence of the meshing precision error between the motor gear and the gear ring: The meshing precision between the motor gear and the gear ring includes tooth profile precision, meshing clearance, etc. If the precision is insufficient, impacts, vibrations, and uneven wear will occur. If the meshing clearance is too large, there will be an idle stroke during the power transmission process, resulting in a lag in the guide vane angle adjustment; if the tooth profile precision is poor, the force on the gear will be uneven, accelerating wear, affecting the smoothness and accuracy of the transmission, and ultimately causing an adjustment error of the guide vane and affecting the engine performance.

[0079] (4) Influence of the connection precision error between the chain plate and related components: The connection precision between the long chain plate and the fixed cylinder, the short shaft, and between the long chain plate and the short shaft, the guide vane is crucial for force transmission and guide vane adjustment. Insufficient connection precision, such as exceeding the tolerance of the fit, improper bolt pre-tightening force, etc., will limit the flexibility of the chain plate movement, reduce the force transmission efficiency and make it uneven. During the guide vane adjustment process, the axial movement of the threaded sleeve cannot be accurately converted into the torque adjustment required for the guide vane, resulting in inconsistent rotation angles of the guide vanes, affecting the synchronous adjustment, and further affecting the engine performance.

[0080] Ways to achieve the synchronism of the guide vanes:

[0081] (1) Precise transmission structure design:

[0082] a. Transmission between the gear ring and the motor gear: The gear ring is installed in cooperation with the outer casing to ensure no axial movement, and the meshing teeth on the outer periphery of the gear ring are precisely meshed with the motor gear. The motor gear combination uses an appropriate module, pressure angle, and material to ensure tooth profile precision and meshing performance. The motor gear is reliably connected to the motor shaft to stably transmit the circumferential movement force output by the motor to the gear ring, enabling the gear ring to drive the subsequent components to move, providing the accuracy and stability of the basic power transmission for the synchronous adjustment of the guide vanes.

[0083] b. Design of the chain plate transmission link: The long chain plate is rotatably connected to the fixed cylinder of the threaded sleeve, the short shaft connects the short chain plate and the long chain plate, and the short chain plate and the guide vane petiole are connected by bolts to form a stable transmission link. Appropriate fitting methods and bearing structures are used at each connection part, such as the high-precision bearing connection between the long chain plate and the fixed cylinder, the special fitting bearing between the short shaft and the chain plate, etc., to ensure that the chain plate can accurately transmit torque during movement, convert the axial movement of the threaded sleeve into the synchronous torque adjustment of the guide vane, and enable the guide vanes to rotate synchronously according to the predetermined angle and torque requirements.

[0084] (2) Processing and assembly control of high-precision components:

[0085] a. Assurance of component processing accuracy: The gear ring adopts the hobbing process to ensure that the tooth profile accuracy reaches above grade 6 and meshes well with the motor gear; the slideway of the threaded sleeve is processed by electric discharge machining to ensure the width, depth and position accuracy (width 3 - 5 mm, depth 5 - 8 mm, position accuracy ±0.1 degree), and the surface is chrome-plated to improve wear resistance and hardness, ensuring stable axial movement of the threaded sleeve without radial deflection; the holes and shafts at the connecting parts of the chain plates are processed according to precise tolerances, such as the interference fit between the short shaft and the long chain plate (interference amount 0.03 - 0.06 mm), etc., to ensure the connection accuracy and the accuracy of force transmission, and ensure the accuracy of the guide vane synchronous adjustment from the source of component processing.

[0086] b. Control of assembly accuracy: During the assembly process, install each component strictly in accordance with the sequence and requirements. For example, first install the gear ring on the outer casing to ensure the fitting accuracy and the smoothness of the lubrication channel, then install the motor reducer, the motor gear combination, etc. in sequence and adjust the meshing clearance, install the threaded sleeve and related components, and finally connect the short chain plate and the guide vane. Pay attention to the fitting accuracy and lubrication condition of each connecting part during the installation process, check the movement flexibility and connection reliability of the mechanism, and ensure the accuracy and stability of the entire transmission system through precise assembly to achieve the synchronous adjustment of the guide vanes.

[0087] (3) Cooperative work of the control and monitoring system:

[0088] a. Precise control of the motor reducer: The motor reducer is equipped with a high-precision encoder and an intelligent controller. The encoder monitors the motor speed and rotation angle in real time and provides accurate feedback (accuracy ±0.1°). The controller accurately controls the transmission ratio by adjusting the input voltage and current of the motor according to the engine working condition requirements, so that the power output by the motor can meet the requirements of the guide vane synchronous adjustment under different working conditions, ensuring that each guide vane obtains accurate and consistent adjustment power.

[0089] b. Monitoring and feedback adjustment of the guide vane angle: Angle sensors may be installed on the guide vane handle or shaft (although not explicitly mentioned in the document but a common control method), which monitors the rotation angle of the guide vane in real time and feeds it back to the control system. The control system compares the feedback information with the target angle. If it is found that the guide vane angles are inconsistent, it timely adjusts the output of the motor reducer to finely adjust the guide vane angle, ensuring that the guide vanes always remain synchronous during the entire adjustment process, achieving precise control of the engine intake or exhaust parameters, and optimizing the engine performance.

[0090] The diameter of the inner casing is 520 mm, the diameter of the outer casing is 740 mm, and the length of the guide vane is between 80 - 100 mm.

[0091] According to the formula where θ is the rotation angle of the guide vane, z1 is the number of teeth of the motor gear, z2 is the number of teeth of the gear ring, i is the chain plate transmission ratio, and α is the rotation angle of the motor, it is obtained that when the guide vane rotates 1.2 - 1.5°, the motor rotates 3.6 - 4.5°.

[0092] Derive the formula for the relationship between the rotation angle of the motor gear and the guide vane angle

[0093] Principle analysis: The rotation of the motor gear drives the ring gear to rotate. The ring gear drives the guide vane to rotate through the chain plate transmission link, thereby realizing angle adjustment. Let the rotation angle of the motor gear be α, and the change in the guide vane angle be θ.

[0094] Key parameters: The number of teeth of the motor gear is z1, the number of teeth of the ring gear is z2, the chain plate transmission ratio is i (the ratio of the length of the long chain plate to the short chain plate. Assuming the length of the long chain plate is L1 and the length of the short chain plate is L2, then i = L1 / L2), and the radius of the guide vane shaft is r.

[0095] Formula derivation process:

[0096] When the motor gear rotates through an angle α, the angle through which the ring gear rotates

[0097] The rotation of the ring gear is transmitted to the guide vane through the chain plate transmission link. Since the chain plate transmission ratio is i, the angle through which the guide vane shaft rotates

[0098] Derive the formula for the relationship between the intake air volume and the rotation angle of the motor gear

[0099] Principle analysis: The rotation of the motor gear causes the threaded sleeve to move axially, and then drives the guide vane to rotate through the chain plate. The change in the guide vane angle affects the intake air volume. Let the intake air volume be Q, and the rotation angle of the motor gear be α.

[0100] Key parameters: The module of the motor gear is x, the pressure angle is The pitch of the threaded sleeve is p, the intake flow coefficient of the turbine is C, the intake area is A, the intake velocity is v, the initial installation angle of the guide vane is θ0, and the coefficient k (related to the turbine structure and working characteristics) that reflects the influence of the change in the guide vane angle on the intake air volume.

[0101] Formula derivation process:

[0102] Assume the relationship between the rotation angle α of the motor gear and the axial movement distance x of the threaded sleeve is (Derived according to the relationship between the gear circumference and the rotation angle, mz1 is a parameter related to the pitch circle circumference of the motor gear).

[0103] When the axial movement distance of the threaded sleeve is x, one end of the short chain plate will have a corresponding displacement, which will cause the guide vane to rotate. Let the change in the guide vane angle be θ. According to the chain plate transmission principle and geometric relationship (involving complex geometric relationships such as the chain plate length ratio and the radius of the guide vane shaft, the derivation process is simplified), we can obtain (i is the chain plate transmission ratio, r is the radius of the guide vane shaft).

[0104] The intake air volume Q = C×A×v. The change in the guide vane angle will cause a change in the intake air velocity v. Let v = v0(1 + kθ) (where v0 is the intake air velocity at the initial guide vane angle).

[0105] Substitute and into Q = C×A×v0(1 + kθ), and the relationship formula between the intake air volume Q and the rotation angle α of the motor gear can be obtained as

[0106] Ceramic matrix composites, such as silicon carbide (SiC) ceramic matrix composites. Density: generally around 3.0 - 3.2 g / cm 3 or so.

[0107] Flexural strength: can reach 300 - 500 MPa or even higher, and can withstand a certain amount of mechanical stress.

[0108] Thermal conductivity: between 10 - 50 W / (m·K), with good thermal conduction performance, which is conducive to heat dissipation and avoids local overheating.

[0109] Coefficient of thermal expansion: relatively low, usually in the range of 4 - 5×10 -6 / ℃, and can maintain good dimensional stability in high - temperature environments, reducing deformation and stress caused by thermal expansion and contraction.

[0110] Known parameters:

[0111] Guide vane rotation angle 1.2° - 1.5°;

[0112] Pusher distance range: 0.07 mm - 0.09 mm;

[0113] Formula: tanα = xθ·r;

[0114] Substitute parameters for calculation:

[0115] When θ = 1.5°, x = 0.07 mm,

[0116] tanα = 0.07(1.5°·180π)·80≈0.070.02618·80≈29.92,

[0117] α≈arctan(29.92)≈88.1°.

[0118] When θ = 1.2°, x = 0.09 mm,

[0119] tanα = 0.09(1.2°·180π)·80≈0.090.02094·80≈18.61,

[0120] α≈arctan(18.61)≈86.9°,

[0121] The angle range of the wedge block is 86.9° to 88.1°.

[0122] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model, characterized in that: include: A gear ring (10), wherein the gear ring (10) is slidably connected to an outer casing (9), the gear ring (10) is meshed with a motor gear (11), the motor gear (11) is connected to a motor reducer (12), the gear ring (10) is threadedly connected to a threaded sleeve (7), the threaded sleeve (7) passes through a group of guide pillars (8), the guide pillars (8) are fixed in guide holes (9-2) on the outer casing (9), and are used to ensure that the threaded sleeve (7) moves axially without generating radial deflection, the threaded sleeve (8) is connected to one end of a long chain plate (4) through a fixed column, the other end of the long chain plate (4) is connected to one end of a short chain plate (6) through a short shaft (5), the other end of the short chain plate (6) is connected to a guide vane shaft (3-1) of a guide vane (3), and the guide vane shaft (3-1) is installed between the inner casing (1) and the outer casing (9).

2. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: The axial end faces of the gear ring (10) are each provided with at least one annular groove, and the outer casing (9) has a protrusion at a position corresponding to the annular groove, and the protrusion is embedded in the annular groove.

3. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: The inner wall of the threaded sleeve (7) is provided with a ball rolling track, in which balls are installed, and the balls are in contact with the outer wall of the gear ring.

4. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1 or 2, characterized in that: The motor reducer (12) is provided with a total temperature and total pressure composite probe (13) for collecting environmental data and transmitting the data to the control system.

5. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 4, characterized in that: It also includes a control system, which controls the operation of the motor reducer (12).

6. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 5, characterized in that: The motor reducer (12) is connected to a high-precision encoder and an intelligent controller.

7. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: An angle sensor is installed on the guide vane shaft (3-1) to monitor the rotation angle of the guide vane (3) in real time and feed back to the control system.

8. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: The gear ring (10) has a lubrication channel inside, and the lubrication channel adopts a spiral structure.

9. The high-pressure variable-geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: The motor gear (11) and the gear ring (10) both adopt involute tooth profiles, and the pressure angle is 20°.

10. A method for adjusting the high-pressure variable geometry turbine guide vane adjustment mechanism based on a screw model according to claim 1, characterized in that: The method includes: The motor reducer (12) receives a control system command and drives the gear ring (10) to rotate the internal thread of the gear ring through the motor gear (11) so as to mesh with the threaded sleeve (7), thereby converting the rotation into an axial movement of the threaded sleeve (7); The threaded sleeve (7) moves axially along the guide hole of the outer casing (9), and the fixed column moves along with the threaded sleeve (7), driving the short chain plate to rotate around the fixed column. The long chain plate (4) is connected to the short chain plate (6) via a short shaft (5), converting the axial displacement into the swinging motion of the short chain plate (6), and the short chain plate (6) drives the guide vane shaft (3-1) to rotate, thereby changing the angle of the guide vane (3).

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