Turbine machinery rotor system blade group tilt and spin angle precision adjustment device

Abstract

The invention discloses a device for precisely adjusting the inclination and spin angle of a blade group of a turbine machinery rotor system, comprising a brake motor, a rotor, a rotor driving mechanism and a blade shaft; a brake motor is provided at at least one end of the rotor; a rigid cam is provided on a reduction shaft connected to the brake motor, a flexible wheel is connected to a motor connection seat, an outer gear ring is provided on the end of the flexible wheel facing the rigid cam, and a flexible bearing is provided between the outer gear ring and the rigid cam; the blade shaft is supported in the rotor through a bearing; an inner gear ring is provided at the end of the reduction hemispherical gear on the blade shaft, and the inner gear ring is meshed with the outer gear ring on the flexible wheel; a plurality of blades are mounted on the rotor, and an adjusting hemispherical gear meshed with the reduction hemispherical gear is provided at the inner end of the blade. The invention proposes methods such as a blade tiltable design, a large reduction ratio design, a hemispherical gear transmission and an independent drive of a blade adjustment device, which can realize the online and precise adjustment of the blade group tilt and the spin angle of the blade group during high-speed operation of the rotor system.

Description

Technical Field

[0001] The invention belongs to the field of turbine machinery, and in particular relates to a device for accurately adjusting the inclination and spin angle of blade groups of a turbine machinery rotor system. Background Art

[0002] Blades are the core components for energy conversion in turbine machinery rotor systems such as aircraft engines, gas turbines, and air compressors. Their efficient and stable operation under long cycles, variable operating conditions, and wide speeds is of great significance to the safe service of the unit. The strong nonlinear vibration of blades caused by thermal fluid-solid coupling in confined space has always restricted the development of turbine machinery towards high parameters, large capacity, and intelligence. In severe cases, it will lead to blade fatigue fracture, trigger self-excited vibration of the unit, and cause significant economic losses and even casualties to the enterprise. The combination of small dynamic changes in the rotation angle of the blade group of the same-stage rotor or the small dynamic changes in the rotation angle of the blade group of different-stage rotors (between compressor, gas turbine, and power turbine rotor) is an important factor affecting the vibration response and energy conversion efficiency of turbine machinery under continuous non-steady airflow excitation. In addition, the axial tilt of the blade group under sudden external excitation is also one of the reasons for the excessive vibration of the turbine machinery rotor system. If it is not diagnosed early, it may also lead to the above serious consequences.

[0003] At present, the research on blade angle adjustment of turbine machinery rotor system at home and abroad mainly includes the following four methods. The first method is to manually adjust the blade angle after shutdown. This method causes the unit to have a lower operating efficiency, increases the economic cost of the enterprise, and cannot study the dynamic and continuous influence of blade angle change on the aerodynamic performance of the rotor system. Its shortcomings are obvious. The second method uses a screw nut as a transmission mechanism, combined with a guide slide bar, to convert the rotational motion of the motor into a plane movement, and uses the eccentric principle to achieve blade angle adjustment. The third method directly uses hydraulic or pneumatic combined with a guide rail structure to generate output motion, and also uses the eccentric principle to achieve blade angle adjustment. The fourth method uses a bevel gear, face gear or worm gear mechanism to convert the axial rotational motion of the motor into radial blade rotational motion to achieve angle adjustment. Although the second, third and fourth methods can easily achieve the purpose of adjusting the blade angle, the direct use of the motor as the power input method cannot achieve the precise adjustment of the rotation angle of the blade group and the combined adjustment of the rotation angle of the blade groups of different levels of rotors, and the above methods cannot achieve the axial tilt adjustment of the blade group. The fault of vibration exceeding the limit caused by the axial tilt of the blade group cannot be effectively diagnosed, resulting in limited application occasions.

[0004] Therefore, the present invention combines methods such as blade group tiltable design, large reduction ratio design, hemispherical gear transmission, and independent drive of blade adjustment device to propose a precise adjustment device for the tilt and spin angle of blade group of a turbine machinery rotor system, which can realize the axial tilt adjustment of the blade group. The minimum axial tilt angle of the blade is 7°, and the minimum spin angle adjustment can reach 3°. The angles of rotor blade groups of different stages can be adjusted synchronously or in any combination according to actual needs, so as to study the intrinsic relationship between blade group fatigue damage, dynamic changes of assembly micro-spin angles and the aerodynamic performance of the rotor system. It has engineering significance for blade group fault diagnosis, optimization of blade group assembly angle design, improvement of blade group vibration response under continuous non-steady airflow excitation, and improvement of energy conversion efficiency of turbine machinery rotor system. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a device for accurately, synchronously or arbitrarily combining the inclination and spin angles of the blade group of a turbine machinery rotor system, so as to study the intrinsic relationship between the fault diagnosis of the axial inclination of the blade group, the dynamic changes of the tiny spin angles of the blade group assembly and the aerodynamic performance of the rotor system.

[0006] The technical scheme adopted by the present invention is: a device for accurately adjusting the inclination and spin angle of a blade group of a turbine machinery rotor system, comprising a brake motor, a rotor, a rotor driving mechanism and a blade shaft; the rotor is a cylindrical structure, and a brake motor is provided at at least one end of the rotor; the output shaft of the brake motor is connected to the reduction shaft, and a rigid cam is provided on the reduction shaft, and the rigid cam is interference fit with the reduction shaft and axially positioned by a shaft shoulder; the flexible wheel is connected to the rotor by bolts, and an outer gear ring is provided at the end of the flexible wheel facing the rigid cam, and the outer gear ring is located outside the rigid cam, and a flexible bearing is provided between the flexible wheel and the rigid cam; the blade shaft is supported in the rotor by a bearing, and a reduction hemispherical gear is fixedly installed on the blade shaft, and an inner gear ring is provided at the end of the reduction hemispherical gear, and the inner gear ring is meshed with the outer gear ring on the flexible wheel; a plurality of blades are installed on the rotor through an inclination adjustment device, and the plurality of blades are located in the same cross section and are evenly arranged along the circumferential direction; an adjusting hemispherical gear is provided at the inner end of the blade, and the adjusting hemispherical gears of the plurality of blades are respectively meshed with the reduction hemispherical gear.

[0007] In the above-mentioned device for precisely adjusting the inclination and spin angle of the blade group of the turbine machinery rotor system, the rotor comprises a primary rotor and a secondary rotor, the primary rotor and the secondary rotor are coaxial, and the opposite ends are connected by bolts; a motor connecting seat is respectively provided at both ends of the rotor, and a brake motor is respectively provided in the two motor connecting seats; each brake motor is connected to a reduction shaft; a group of blades is respectively provided on the primary rotor and the secondary rotor; a blade shaft is respectively provided in the primary rotor and the secondary rotor, and a reduction hemispherical gear is respectively provided on the two blade shafts, which is meshed with the adjusting hemispherical gear of the blade group on the corresponding primary rotor or the secondary rotor; the reduction hemispherical gears on the two blade shafts are respectively fixedly installed with an inner gear ring, and the inner gear rings on the two reduction hemispherical gears are respectively meshed with the outer gear rings of the flexible wheels on the corresponding reduction shafts.

[0008] In the above-mentioned device for precisely adjusting the inclination and spin angle of the blade group of the turbine machinery rotor system, the rotor driving mechanism includes a driving motor, a driving pulley, a driven pulley, a synchronous belt and a tensioning sleeve; the driving pulley is installed on the output shaft of the driving motor, the driven pulley is installed on the rotor through the tensioning sleeve, and the driving pulley is connected to the driven pulley through a synchronous belt.

[0009] In the above-mentioned device for precisely adjusting the inclination and spin angle of blade groups of a turbine machinery rotor system, the brake motor is electrically connected to an energized slip ring; and the flexible bearing is a thin-walled deep groove ball bearing.

[0010] In the above-mentioned device for precisely adjusting the inclination and spin angle of the blade group of the turbine machinery rotor system, the inclination angle adjustment device includes an adjusting tapered roller bearing, an open retaining ring, a ball head, a slot and an end cover; the rotor is provided with a circular through hole at the blade installation position, and the end cover is covered on the outer end of the circular through hole; the adjusting tapered roller bearing is installed in the circular through hole, and the inner wall of the inner ring is a spherical surface, and the spherical surface cooperates with the ball head to form a ball joint structure; the ball head is installed on the blade, and a plurality of annular slots are provided on the ball head, and the planes where the plurality of annular slots are located form different angles with the plane where the adjusting tapered roller bearing is located, and an open retaining ring is provided on the outer end surface of the inner ring of the adjusting tapered roller bearing, and the open retaining ring cooperates with the slot on the ball head to fix the blade angle.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The present invention can adjust the inclination angle of the blade group of the rotor system to a maximum of 39° and a minimum adjustable inclination angle of 7°, and can effectively diagnose the axial inclination fault of the blade group caused by sudden external excitation.

[0013] 2. The present invention combines a large reduction ratio design with a hemispherical gear transmission method to achieve an online adjustment method for the blade group's minimum spin angle of 3°. Compared with other devices that directly use the motor speed output as power to adjust the spin angle, the present invention is more accurate in adjusting the spin angle of the turbine machinery blade group, which is conducive to studying the intrinsic relationship between the dynamic changes of the blade group assembly's tiny spin angle and the aerodynamic performance of the rotor system.

[0014] 3. The blade adjustment device of the present invention is independently driven, and can realize the synchronous adjustment of the rotation angle of the blade group. It can also realize any combination adjustment of the rotation angle of the blade group of the first-stage rotor and the second-stage rotor according to actual needs, which broadens the scope of application and better meets the actual needs of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention.

[0016] Figure 2 It is a schematic diagram of the blade inclination angle adjustment device of the present invention.

[0017] Figure 1 In the figure: 1 is an energized slip ring, 2 is a brake motor, 3 is a motor connection seat, 4 is a coupling, 5 is a supporting deep groove ball bearing, 6 is a primary rotor, 7 is a flexible wheel, 8 is a rigid cam, 9 is a flexible bearing, 10 is an inner gear ring, 11 is a reduction hemispherical gear, 12 is an adjustment hemispherical gear, 13 is an inclination adjustment device, 14 is a blade, 15 is a sleeve, 16 is an intermediate deep groove ball bearing, 17 is a secondary rotor, 19 is a driven pulley, 20 is a locking sleeve, 21 is a synchronous belt, 22 is a driving pulley, 23 is an AC variable frequency motor, 24 is a primary blade shaft, and 25 is a reduction shaft.

[0018] Figure 2 In the figure: 13-1 is an adjusting tapered roller bearing, 13-2 is an open snap ring, 13-3 is a ball head, 13-4 is a slot, and 13-5 is an end cover. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] like Figure 1As shown, the present invention includes two brake motors, a rotor, a rotor driving mechanism and a blade shaft; the rotor includes a primary rotor 6 and a secondary rotor 17, the primary rotor 6 and the secondary rotor 17 are coaxial, and the opposite ends are connected by bolts, and the rotor is a cylindrical structure. A motor connection seat 3 is provided at each end of the rotor, and a brake motor 2 is provided in each of the two motor connection seats 3. The two brake motors 2 are electrically connected to two energized slip rings 1 respectively, and are powered by the energized slip rings 1. The output shafts of the two brake motors 2 are connected to a reduction shaft 25 through a coupling 4. A rigid cam 8 is provided on the reduction shaft 25, and the rigid cam 8 is interference fit with the reduction shaft 25 and is axially positioned by a shaft shoulder. The two motor connection seats 3 are connected to the flexible wheel 7 by bolts, and the flexible wheel 7 is provided with an outer gear ring facing the rigid cam 8, and the outer gear ring is located outside the rigid cam 8. A flexible bearing 9 is provided between the outer gear ring and the rigid cam 8, and the flexible bearing 9 adopts a thin-walled deep groove ball bearing. A blade shaft 24 is provided in each of the primary rotor 6 and the secondary rotor 17. One end of the blade shaft 24 is mounted on one end of the reduction shaft 25 through the supporting deep groove ball bearing 5, and the other end of the blade shaft 24 is supported in the rotor through the intermediate deep groove ball bearing 16. A group of blades 14 is provided on each of the primary rotor 6 and the secondary rotor 17; the multiple blades of each group of blades 14 are located in the same plane, and the blades are mounted on the rotor through the inclination adjustment device 13. Each blade is equipped with an adjusting hemispherical gear 12, and a reduction hemispherical gear 11 is provided on the blade shaft 24, which is meshed with the adjusting hemispherical gear 12 of the blade group on the corresponding primary rotor 6 or the secondary rotor 17. An inner gear ring 10 is fixedly mounted on the end face of the reduction hemispherical gear 11, and the inner gear ring 10 is meshed with the outer gear ring of the flexible wheel 7 on the corresponding motor connection seat 3.

[0021] The rotor driving mechanism includes an AC variable frequency motor 23, a driving pulley 22, a driven pulley 19, a synchronous belt 21 and a tension sleeve 20; the driving pulley 22 is mounted on the output shaft of the driving motor 23, the driven pulley 19 is mounted on the rotor through the tension sleeve 20, and the driving pulley 22 is connected to the driven pulley 19 through the synchronous belt 21. When the AC variable frequency 23 is started, the rotor can be driven to rotate through the synchronous belt 21.

[0022] like Figure 2As shown, the tilt adjustment device 13 includes an adjustment tapered roller bearing 13-1, an open snap ring 13-2, a ball head 13-3, a slot 13-4 and an end cover 13-5; the rotor is provided with a circular through hole at the installation position of the blade 14, the end cover 13-5 covers the outer end of the circular through hole, and the blade extends from the center hole of the end cover 13-5. The adjustment tapered roller bearing 13-1 is installed in the circular through hole, and the inner wall of the inner ring of the adjustment tapered roller bearing 13-1 is a spherical surface, and the spherical surface cooperates with the ball head 13-3 to form a ball joint structure. The ball head 13-3 is installed on the blade 14, and a plurality of annular grooves 13-4 are provided on the ball head 13-3. The planes where the plurality of annular grooves 13-4 are located form different angles with the plane where the adjusting tapered roller bearing 13-1 is located. An open snap ring 13-2 is provided on the outer end surface of the inner ring of the adjusting tapered roller bearing 13-1. The open snap ring 13-2 cooperates with a groove on the ball head 13-3 to fix the angle of the blade 14, and cooperates with different grooves 13-4 to adjust the angle between the blade 14 and the rotor axis.

[0023] In the specific operation of the present invention, the relative positions of the open clamp ring 13-2 and the annular clamping groove 13-4 are first changed according to actual needs to achieve blade tilting, and then the AC variable frequency motor 23 is started to drive the primary rotor 6 and the secondary rotor 17 to rotate, and the brake motor 2 is kept in the braking state. When adjusting the blade spin angle, the rotation time of the brake motor 2 is calculated according to the following formula:

[0024] ; Where: α is The blade 14 spins at an angle, n is the speed of brake motor 2, I 34 To reduce the speed of the hemispherical gear 11 and adjust the transmission ratio of the hemispherical gear 12; I 12 is the transmission ratio of the outer gear ring of the flexible wheel 7 and the inner gear ring 10.

[0025] After the adjustment is completed, a command is issued to the brake motor 2 to maintain the brake state again, ensuring that the blades 14 run stably and reliably at the adjusted angle. If the spin angles of the blades on the primary rotor and the secondary rotor are the same, the spin angles of the blades 14 on the primary rotor and the secondary rotor can be adjusted synchronously. If they are inconsistent, any combination of the spin angles of the blades on the primary rotor and the secondary rotor can be adjusted.

[0026] The following is a specific example: the number of teeth of the reduction hemispherical gear 11 is Z 3 =30, adjust the number of teeth of hemispherical gear 12 to Z 4 =20, the relative position coefficient of the two d=1.667, the transmission ratio of the reduction hemispherical gear 11 and the adjustment hemispherical gear 12 is set to ; The number of teeth of the outer ring gear of the flexible wheel 7 is Z 1 =478, the number of teeth of the inner ring 10 is Z 2 =480, the transmission ratio of the outer gear ring 7 and the inner gear ring 10 of the flexible wheel is , the speed of brake motor 2 is n =100r / min, if the blade 14 of the first-stage rotor is to rotate at an angle of 3° each time, it can be calculated that the rotation time t of the brake motor 2 is 3s.

Claims

1. A device for accurately adjusting the inclination and spin angle of blades of a turbine machinery rotor system, characterized in that: It includes a brake motor, a rotor, a rotor driving mechanism and a blade shaft; the rotor is a cylindrical structure, and a brake motor is provided at least at one end of the rotor; the output shaft of the brake motor is connected to the reduction shaft, and a rigid cam is provided on the reduction shaft, the rigid cam is interference fit with the reduction shaft, and is axially positioned by a shaft shoulder; the flexible wheel is connected to the rotor by bolts, and an outer gear ring is provided on the end of the flexible wheel facing the rigid cam, the outer gear ring is located on the outside of the rigid cam, and a flexible bearing is provided between the flexible wheel and the rigid cam; the blade shaft is supported in the rotor by a bearing, and a reduction hemispherical gear is fixedly installed on the blade shaft, and an inner gear ring is provided at the end of the reduction hemispherical gear, and the inner gear ring is meshed with the outer gear ring on the flexible wheel; a plurality of blades are installed on the rotor through an inclination adjustment device, and the plurality of blades are located in the same cross section and are evenly arranged along the circumferential direction; an adjusting hemispherical gear is provided at the inner end of the blade, and the adjusting hemispherical gears of the plurality of blades are respectively meshed with the reduction hemispherical gear.

2. The device for precisely adjusting the inclination and spin angle of blades of a turbine machinery rotor system according to claim 1, characterized in that: The rotor comprises a primary rotor and a secondary rotor, which are coaxial and connected at opposite ends by bolts; a motor connection seat is provided at each end of the rotor, and a brake motor is provided in each of the two motor connection seats; each brake motor is connected to a reduction shaft; a group of blades are provided on the primary rotor and the secondary rotor respectively; a blade shaft is provided in each of the primary rotor and the secondary rotor respectively, and a reduction hemispherical gear is provided on each of the two blade shafts respectively, which meshes with an adjusting hemispherical gear of the blade group on the corresponding rotor; the reduction hemispherical gears on the two blade shafts are respectively fixed with an inner gear ring, and the inner gear rings on the two reduction hemispherical gears are respectively meshed with the outer gear rings of the flexible wheels on the corresponding reduction shafts.

3. The device for precisely adjusting the inclination and spin angle of blades of a turbine machinery rotor system according to claim 1 or 2, characterized in that: The rotor driving mechanism comprises a driving motor, a driving pulley, a driven pulley, a synchronous belt and a tension sleeve; the driving pulley is installed on the output shaft of the driving motor, the driven pulley is installed on the rotor through the tension sleeve, and the driving pulley is connected to the driven pulley through the synchronous belt.

4. The device for precisely adjusting the inclination and spin angle of blades of a turbine machinery rotor system according to claim 1 or 2, characterized in that: The brake motor is electrically connected to the energized slip ring; the flexible bearing is a thin-walled deep groove ball bearing.

5. The device for precisely adjusting the inclination and spin angle of blades of a turbine machinery rotor system according to claim 1 or 2, characterized in that: The inclination adjustment device comprises an adjusting tapered roller bearing, an open snap ring, a ball head, a slot and an end cover; the rotor is provided with a circular through hole at the blade installation position, and the end cover is covered on the outer end of the circular through hole; the adjusting tapered roller bearing is installed in the circular through hole, the inner wall of the inner ring is a spherical surface, and the spherical surface cooperates with the ball head to form a ball joint structure; the ball head is installed on the blade, and a plurality of annular slots are provided on the ball head, and the planes where the plurality of annular slots are located form different angles with the plane where the adjusting tapered roller bearing is located, and an open snap ring is provided on the outer end surface of the inner ring of the adjusting tapered roller bearing, and the open snap ring cooperates with the slot on the ball head to fix the blade angle.

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