A rotor radial excitation simulation device with adjustable vortex amplitude and frequency

Abstract

The present invention discloses a rotor radial excitation simulation device with adjustable vortex amplitude and frequency, comprising a test seal module, an excitation shaft, a drive disc assembly provided at both ends of the excitation shaft, a drive motor, and a drive module connected to the drive motor in a transmission manner, wherein the drive disc assembly includes a drive disc, and two driven rollers are provided on the outer circumference of the drive disc. The drive module includes a gearbox and two drive cams. The drive motor is connected to the two drive cams through the gearbox, and each driven roller is in contact with the outer circumference of each drive cam. The rotation of the drive cam drives the excitation shaft to perform radial vortex with controllable amplitude and frequency. By using the drive cam and the excitation shaft module, the present invention can regulate the frequency and amplitude of high-frequency vortex of the cylindrical seal at high speed, so as to simulate different excitation forms in actual working conditions and explore the wear pattern and sealing performance of the sealing device.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation engine sealing, and in particular relates to a rotor radial excitation simulation device with adjustable vortex amplitude and frequency. Background Art

[0002] Cylindrical seals are critical components widely used in aircraft engine main bearing cavities, protecting bearings and lubricating oil from damage caused by high-temperature gas intrusion and preventing lubricating oil leakage. When aircraft engines operate at high speeds, high speeds and rotor eccentricity cause high-frequency radial vortex motion on the outer surface of the seal rotor. Cylindrical seals are classified into contact seals and non-contact seals.

[0003] Contact sealing devices include contact graphite circumferential seals and packing sealing devices. Among them, contact graphite circumferential seals are mostly used for aero-engine seals. There are two core problems with aero-engine contact graphite circumferential seals: first, the high-frequency radial vortex of the rotating shaft causes micro-wear between the anti-rotation pin and the side wall of the anti-rotation groove of the graphite ring; second, the tightening spring contacts and rubs against the outer periphery of the graphite ring due to high-frequency excitation. The former is because under the action of the friction torque load of the main sealing surface, the radial vortex of the rotating shaft runway causes high-frequency reciprocating micro-wear between the fixed anti-rotation pin installed on the sealing seat and the side wall of the anti-rotation groove of the graphite ring; the latter is because under the action of the high-frequency rotation excitation of the rotating shaft, the tightening spring vibrates and contacts and rubs against the outer periphery of the graphite ring.

[0004] Non-contact sealing devices include floating ring seals, labyrinth seals, and dynamic pressure circumferential sealing devices. The eccentric vortex of the rotor will cause the sealing gap to be unevenly distributed in the circumferential direction, destroying the symmetry of the lubricating film. The oil film in the small gap area is too thin, which may cause boundary friction or dry friction, aggravating wear; the large gap area may reduce the sealing effect and increase leakage. The above problems seriously affect the life and reliability of the seal, and a test platform that can accurately simulate the actual working conditions is urgently needed. It is necessary to construct a high-frequency radial vortex excitation device for the rotor, so as to better realize the friction and wear behavior of the above two types of seals in the cylindrical seal, and then study the influence of high-frequency radial vibration of the shaft on the performance of the cylindrical sealing device.

[0005] Currently, in the research on sealing excitation devices, there are excitation devices that can be used to simulate external disturbances. The magnitude of the excitation applied to the sealing surface is controlled by setting up a pressure regulating chamber, or the excitation frequency is preset by the exciter to simulate high-frequency vortex conditions. However, the excitation frequency applied by the pressure regulating chamber is low and cannot simulate the excitation caused by the high speed of the aircraft engine. The exciter is expensive, has a fixed frequency, and is complicated to install and disassemble, making it impossible to realize the study of multi-frequency and multi-amplitude radial excitation conditions. In the existing research on mechanical seal excitation test devices, a single multi-line cam drive mechanism is used to achieve excitation control, but it can only simulate the axial vibration of the sealing ring and is only suitable for excitation simulation at the end face of the mechanical seal. It cannot reproduce the complex multi-modal excitation (such as radial circular, elliptical vortex and angular deflection) in the actual working conditions of the cylindrical seal. Therefore, it is necessary to construct a cylindrical seal radial vortex excitation device with controllable excitation form, diverse excitation frequency amplitude, and simple structure. Summary of the Invention

[0006] In response to the problems in the prior art such as increased wear of cylindrical contact seals due to high-frequency radial vortex of the rotating shaft, wear and increased leakage of non-contact seals, and degradation of sealing performance of the main sealing surface, the present invention provides a rotor radial excitation simulation device with adjustable vortex amplitude and frequency.

[0007] The technical solution of the present invention is:

[0008] A rotor radial excitation simulation device with adjustable vortex amplitude and frequency comprises a test sealing module, an excitation shaft passing through the test sealing module and movably connected thereto, two groups of drive disc assemblies respectively arranged at both ends of the excitation shaft, a drive motor and two groups of drive modules respectively arranged on both sides of the drive motor and transmission-connected thereto, each group of drive disc assemblies comprises a drive disc fixedly connected to the end of the excitation shaft, a first driven roller and a second driven roller are provided on the outer circumference of the drive disc, each group of drive modules comprises a gear box, a first drive cam and a second drive cam, the drive motor is transmission-connected to the first drive cam and the second drive cam through the gear box, the first driven roller is in contact with the outer circumference of the first drive cam, and the second driven roller is in contact with the outer circumference of the second drive cam, and the excitation shaft is driven by the rotation of the first drive cam and the second drive cam to perform radial vortex with controllable amplitude and frequency.

[0009] Furthermore, it also includes supporting accessories, which include a lower base plate seat and a side plate support vertically arranged on the upper surface of the lower base plate seat. The drive motor and the gear box are fixed on the lower base plate seat. The test sealing module includes a sealing assembly and a rotor. The sealing assembly is fixed on the side plate support, and the rotor is installed in the middle of the excitation shaft to realize the transmission of excitation.

[0010] Furthermore, a third driven roller is provided on the outer circumference of the driving disk, and a tension assembly is provided above each group of driving disk assemblies. The tension assembly includes an upper pressure plate and a tensioning spring. One end of the upper pressure plate is fixed on the side plate support, and the other end extends horizontally outward and is connected to the upper end of the tensioning spring. The lower end of the tensioning spring is fixed on the lower base plate seat. The lower surface of the upper pressure plate is in contact with the third driven roller and applies a downward force to it.

[0011] Furthermore, the gearbox includes an input shaft, a first output shaft and a second output shaft. The drive motor drives the first output shaft and the second output shaft to rotate through the input shaft. The first drive cam is installed at the end of the first output shaft, and the second drive cam is installed at the end of the second output shaft.

[0012] Furthermore, a displacement sensor group is fixed on the lower base plate seat, and the displacement sensor group is in contact with the excitation shaft and is used to monitor the axis trajectory of the excitation shaft.

[0013] Furthermore, an axial limiting disk is provided on the excitation shaft between the drive disk assembly and the test sealing module. The axial limiting disk limits the axial position of the excitation shaft by contacting the ball pin assembly fixed on the gear box to prevent the occurrence of small axial displacement.

[0014] Furthermore, the waveforms of the outer circumferential surfaces of the first drive cam and the second drive cam are sinusoidal, rectangular or triangular waves, and the excitation amplitude is adjusted by replacing the first drive cam and the second drive cam with different peak heights; the excitation frequency is adjusted by adjusting the speed of the drive motor and installing the first drive cam and the second drive cam with different periods, and angular deflection excitation is applied by changing the phase angle of the first drive cam and the second drive cam.

[0015] Furthermore, a slide rail is provided on the lower base plate seat, and the slide rail is located on the outside of the gear box. A transparent protective cover is provided on each side of the slide rail, and the transparent protective cover moves along the slide rail to protect the rotor radial excitation simulation device.

[0016] The working principle of the present invention is:

[0017] When the present invention is used to apply radial excitation to a cylindrical sealing device, two symmetrically arranged drive discs are fixed at each end of the excitation shaft. Three driven rollers are arranged around the drive discs: two located at the bottom, referred to as the first and second driven rollers, and one located at the top, referred to as the third driven roller. The lower portion is equipped with a coaxial drive motor at both ends and two symmetrically arranged gearboxes. Each gearbox extends two output shafts, referred to as the first and second output shafts, with coplanar axes and parallel to the lower base. The first and second output shafts are respectively fixed to their ends with first and second drive cams. The key of the present invention is that the outer periphery of the driving cam is processed with a periodic sinusoidal cam profile, the number and amplitude of the sinusoidal waves of which can be changed, the first driven roller is in contact with the outer periphery of the first driving cam, and the second driven roller is in contact with the outer periphery of the second driving cam, so that when the cam rotates, the friction between its outer periphery and the roller is rolling friction rather than sliding friction, thereby reducing the wear of the cam periphery and extending the service life; in order to prevent the driving cam and the driven roller from detaching, an upper pressure plate is installed above the driving disk assembly, the fixed end of the upper pressure plate is fixed to the side plate support, and the free end is connected to the lower base plate seat by a tensioning spring, and the upper pressure plate is deformed by the force of the tensioning spring and contacts the third driven roller, thereby providing a downward force to the driving disk, and the downward force can be changed by adjusting the stiffness and elongation of the tensioning spring, thereby keeping the first and second driven rollers in contact with the corresponding driving cams at all times while also having a smaller driving resistance. When the amplitude and phase of the two cams are the same, the track radial vortex trajectory is circular; when the phases of the two cams are the same but the amplitudes are different, the track radial vortex trajectory is elliptical, and at the limit (the amplitude of a certain driving cam profile is 0), the trajectory is a straight line.

[0018] When angular runout excitation is required for the cylindrical seal, the trajectory phases of the first and second drive cams at either end of the output shaft are adjusted to different values. The application of these different phase angles is achieved by adjusting the angle between the cam key engagement and the cam's initial phase. The trajectory rotational surface formed by the centerline of the runway axis is a biconical surface, enabling the construction of angular runout excitation. Maintaining the phase angles of the four drive cams is crucial for achieving quantitative control of runway radial vortex excitation and angular runout excitation.

[0019] The beneficial effects of the present invention are:

[0020] (1) It can accurately simulate the radial circular excitation, radial elliptical excitation, and angular yaw excitation of the cylindrical seal during actual operation, and can achieve different vortex frequencies, amplitudes, and vortex shapes by driving the sine wave designed on the cam, providing a reliable test platform for experimental research on the wear effects of cylindrical seals caused by different high-frequency vortices;

[0021] (2) The overall structure is compact, and the excitation and cam are easy to control. The excitation frequency can be controlled by changing the speed of the DC motor or the number of sine wave cycles of the driving cam, and the excitation amplitude can be controlled by using driving cams with different sine wave amplitudes.

[0022] (3) When the drive disc assembly is driven, the friction between the first and second drive cams and the first and second driven rollers, and between the upper pressure plate and the third driven roller is designed to be rolling friction, which can reduce the friction wear of each contact friction surface and extend the service life of parts such as the drive cam. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the three-dimensional structure of the entire excitation and sealing device of an embodiment of the present invention;

[0024] Figure 2 This is a front view of the entire excitation device according to an embodiment of the present invention;

[0025] Figure 3 This is a cross-sectional view of the excitation shaft module structure of an embodiment of the present invention;

[0026] Figure 4 3D structural diagram of a sinusoidal line driven cam according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the three-dimensional structure of the triangle wave in the cam profile of the present invention;

[0028] Figure 6 Schematic diagram of a drive disc assembly and a drive cam for applying radial excitation according to embodiment 1 of the present invention;

[0029] Figure 7 This is a schematic diagram of the drive disc assembly and the drive cam used for applying angular deflection excitation in Example 2 of the present invention.

[0030] In the figure: 1. Test sealing module; 11. Sealing assembly; 12. Rotor; 2. Excitation shaft; 21. Axial limiting disk; 3. Drive disk assembly; 31. Drive disk; 32. First driven roller; 33. Second driven roller; 34. Third driven roller; 4. Drive motor; 5. Drive module; 51. Gearbox; 511. Input shaft; 512. First output shaft; 513. Second output shaft; 52. First drive cam; 53. Second drive cam; 54. Ball pin assembly; 6. Support attachment; 61. Lower base plate seat; 62. Side plate support; 63. Transparent protective cover; 7. Tension assembly; 71. Upper pressure plate; 72. Tension spring; 8. Displacement sensor group; 9. Slide rail. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the protection scope of the present invention is not limited thereto.

[0032] Example 1

[0033] Reference Figure 1-3 and 6, a rotor radial excitation simulation device with adjustable vortex amplitude and frequency, comprising a test sealing module 1, an excitation shaft 2, a drive disc assembly 3, a drive motor 4, a drive module 5, a support accessory 6, a tension assembly 7, a displacement sensor group 8, and a slide rail 9.

[0034] The test sealing module 1 includes a sealing assembly 11 and a rotor 12. The excitation shaft 2 passes through the test sealing module 1 and is movably connected thereto. For different cylindrical sealing devices, the sealing assembly 11 and the rotor 12 are structurally different, but both connect the assembly where the rotating sealing surface is located to the excitation shaft 2 to achieve radial excitation during simulated rotation.

[0035] Two groups of symmetrically arranged drive disc assemblies 3 are respectively arranged at both ends of the excitation shaft 2. Each group of drive disc assemblies 3 includes a drive disc 31, a first driven roller 32, a second driven roller 33 and a third driven roller 34. The end of the excitation shaft 2 is axially fixed to the drive disc 31 and is tightened by a threaded nut. This connection method can adapt to higher excitation frequencies and prevent loosening. The first driven roller 32 and the second driven roller 33 are respectively arranged on the outer circumference of the lower part of the drive disc 31, and the third driven roller 34 is arranged on the outer circumference of the upper part of the drive disc 31.

[0036] Two groups of symmetrically arranged drive modules 5 are arranged on both sides of the drive motor 4. Each group of drive modules 5 includes a gearbox 51, a first drive cam 52, a second drive cam 53 and a ball pin assembly 54. The gearbox 51 includes an input shaft 511, a first output shaft 512 and a second output shaft 513. The drive motor 4 drives the first output shaft 512 and the second output shaft 513 to rotate through the input shaft 511. The first drive cam 52 is installed at the end of the first output shaft 512, and the two are connected by key transmission. The second drive cam 53 is installed at the end of the second output shaft 513, and the two are connected by key transmission. The first driven roller 32 is in contact with the outer circumference of the first drive cam 52, and the second driven roller 33 is in contact with the outer circumference of the second drive cam 53. The rotation of the first drive cam 52 and the second drive cam 53 drives the excitation shaft 2 to perform radial vortex with controllable amplitude and frequency. The speed of the four drive cams can be adjusted by changing the output speed of the drive motor 4, thereby adjusting the frequency of the vortex excitation. An axial limiting disk 21 is provided on the excitation shaft 2 between the drive disk assembly 3 and the test sealing module 1. The axial limiting disk 21 limits the axial position of the excitation shaft 2 by contacting the ball pin assembly 54 fixed on the gear box 51 to prevent the occurrence of small axial displacement.

[0037] The supporting accessory 6 includes a lower base plate seat 61, a side plate support 62 vertically arranged on the upper surface of the lower base plate seat 61, and a transparent protective cover 63. The drive motor 4 and the gear box 51 are fixed on the lower base plate seat 61, and the sealing assembly 11 is fixed on the side plate support 62. Four symmetrically installed slide rails 9 are also provided on the lower base plate seat 61. The slide rails 9 are located on the outside of the gear box 51. A transparent protective cover 63 is provided on the slide rails 9 on each side. The transparent protective cover 63 moves along the slide rails 9 to protect the rotor radial excitation simulation device. On the one hand, it can ensure the safety of the test and prevent safety accidents during high-speed operation; on the other hand, the transparent protective cover 63 ensures the visibility of the test process.

[0038] Two groups of symmetrically arranged tension components 7 are respectively arranged above the driving disk component 3. Each group of tension components 7 includes an upper pressure plate 71 and a tensioning spring 72. One end of the upper pressure plate 71 is fixed on the side plate support 62, and the other end extends horizontally outward and is connected to the upper end of the tensioning spring 72. The lower end of the tensioning spring 72 is fixed on the lower base plate seat 61. The lower surface of the upper pressure plate 71 is in contact with the third driven roller 34 and applies a downward force to it to ensure the follow-up performance of the excitation shaft 2 during radial excitation.

[0039] Two symmetrically arranged displacement sensor groups 8 are also fixed on the lower base plate seat 61 . The displacement sensor groups 8 are in contact with the excitation shaft 2 and are used to monitor the axis trajectory of the excitation shaft 2 .

[0040] The first driving cam 52 and the second driving cam 53 are one of the core components of the present invention, which are connected to the first output shaft 512 and the second output shaft 513 of the gear box 51 through keys and transmit torque. Figure 6 As shown, the outer surfaces of the first and second drive cams 52 and 53 in this example are provided with multi-periodic, identically phased sinusoidal curves. Each set of sinusoidal curves includes peaks and troughs. When the two cams have the same amplitude and phase, the radial vortex trajectory is circular. When the two cams have the same phase but different amplitudes, the radial vortex trajectory is elliptical. At the extreme (when the amplitude of one drive cam profile is zero), the trajectory becomes a straight line. The excitation shape can be directly controlled by varying the phase and amplitude of the sinusoidal curves, and the excitation frequency can be directly controlled by varying the number of sinusoidal cycles.

[0041] Implementation method of excitation parameter control: the amplitude is adjusted by replacing cams with different peak heights; the frequency is adjusted by adjusting the speed of the drive motor 4 through the frequency converter and installing a multi-cycle cam.

[0042] Excitation implementation process: After the device is installed, ensure that the first drive cam 52 and the second drive cam 53 are aligned with the first driven roller 32 and the second driven roller 33 respectively; check whether the preload force of the tensioning spring 72 is in the initial state without additional stretching, and ensure that the upper pressure plate 71 is in contact with the third driven roller 34 but not over-pressed; after turning on the power, run it at 10% of the rated speed for 5 minutes without load, and observe whether the rotation of each roller is smooth without abnormal friction or jamming; monitor the vortex trajectory in real time through the displacement sensor group 8, and use an oscilloscope to observe the XY displacement Signal phase relationship; increase the speed in steps of 10 Hz, maintain each step for 1 minute to observe the vibration stability; if the followability of the driven roller is found to be insufficient during high-frequency operation (such as unstable contact between the roller and the cam), increase the downward clamping force by adjusting the preload of the tensioning spring 72 (such as increasing the spring stiffness or elongation); when the target frequency is reached, record the axis trajectory of the excitation shaft 2 (such as a circle or an ellipse) through the displacement sensor group 8 and compare it with the theoretical waveform; keep the transparent protective cover 63 closed throughout the test to prevent parts from splashing during high-speed operation.

[0043] The waveform of the outer circumference of the first driving cam 52 and the second driving cam 53 is a sine wave (such as Figure 4 As shown), rectangular wave (as Figure 5 The figure only illustrates the waveform of the first driving cam 52. The structure of the second driving cam 53 is the same as that of the first driving cam 52. The high point of the outer circumference is the peak and the low point is the trough.

[0044] Example 2

[0045] refer to Figure 7 This embodiment differs from Example 1 in that the outer surfaces of the first and second drive cams 52 and 53 are characterized by a multi-periodic distribution of sinusoidal curves with identical amplitudes but different phases. The different phase angles are applied by adjusting the angle between the key engagement point of the drive cams and the initial phase of the drive cams. By properly adjusting the phase angles, the trajectory formed by the centerline of the runway axis can be made into a biconical surface. This implementation is primarily used to simulate the circumferential seal device under angular runout excitation.

[0046] Excitation implementation process: replace the cam used in Example 1, install two sinusoidal waveform first drive cam 52 and second drive cam 53 with the same amplitude but a phase difference of a set value; by adjusting the matching angle of the cam keyway and the first output shaft 512 and the second output shaft 513 key or the cam keyway angle during the profile processing, the phase difference is adjusted. Figure 7 For example, the keyway of the first drive cam 52 is rotated to a set angle, while the second drive cam 53 remains in place to form a corresponding phase difference; the speed of the drive motor 4 is set by the frequency converter to ensure that the two cams rotate synchronously and the phase difference is stable; the other processes are the same as in Example 1.

[0047] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The scope of protection of the present invention should not be regarded as limited to the specific forms described in the embodiments. The scope of protection of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A rotor radial excitation simulation device with adjustable vortex amplitude and frequency, characterized in that: The invention comprises a test sealing module (1), an excitation shaft (2) passing through the test sealing module (1) and movably connected thereto, two sets of drive disc assemblies (3) respectively arranged at both ends of the excitation shaft (2), a drive motor (4), and two sets of drive modules (5) respectively arranged at both sides of the drive motor (4) and transmission-connected thereto, wherein each set of drive disc assemblies (3) comprises a drive disc (31) fixedly connected to the end of the excitation shaft (2), a first driven roller (32) and a second driven roller (33) being provided on the outer circumference of the drive disc (31), and each set of drive modules (5) The invention comprises a gear box (51), a first driving cam (52) and a second driving cam (53); a driving motor (4) is connected to the first driving cam (52) and the second driving cam (53) through the gear box (51); a first driven roller (32) is fitted with the outer peripheral surface of the first driving cam (52); and a second driven roller (33) is fitted with the outer peripheral surface of the second driving cam (53); and the first driving cam (52) and the second driving cam (53) are rotated to drive the excitation shaft (2) to perform radial vortex motion with controllable amplitude and frequency; The waveforms of the outer circumferential surfaces of the first driving cam (52) and the second driving cam (53) are sinusoidal, rectangular or triangular waves, and the excitation amplitude is adjusted by replacing the first driving cam (52) and the second driving cam (53) with different peak heights; the excitation frequency is adjusted by adjusting the speed of the driving motor (4) and installing the first driving cam (52) and the second driving cam (53) with different cycles; and angular deflection excitation is applied by changing the phase angle of the first driving cam (52) and the second driving cam (53).

2. A rotor radial excitation simulation device with adjustable vortex amplitude and frequency as claimed in claim 1, characterized in that: The test seal module (1) further includes a support accessory (6), the support accessory (6) including a lower base plate seat (61) and a side plate support (62) vertically arranged on the upper surface of the lower base plate seat (61), the drive motor (4) and the gear box (51) are fixed on the lower base plate seat (61), the test seal module (1) includes a seal assembly (11) and a rotor (12), the seal assembly (11) is fixed on the side plate support (62), and the rotor (12) is installed in the middle of the excitation shaft (2) to achieve the transmission of the excitation.

3. The rotor radial excitation simulation device with adjustable vortex amplitude and frequency according to claim 2, characterized in that: A third driven roller (34) is also provided on the outer circumference of the driving disc (31), and a tension assembly (7) is provided above each set of driving disc assemblies (3). The tension assembly (7) includes an upper pressure plate (71) and a tension spring (72). One end of the upper pressure plate (71) is fixed to the side plate support (62), and the other end extends horizontally outward and is connected to the upper end of the tension spring (72). The lower end of the tension spring (72) is fixed to the lower base plate seat (61). The lower surface of the upper pressure plate (71) is in contact with the third driven roller (34) and applies a downward force to it.

4. The rotor radial excitation simulation device with adjustable vortex amplitude and frequency as claimed in claim 3, characterized in that: The gear box (51) includes an input shaft (511), a first output shaft (512), and a second output shaft (513). The drive motor (4) drives the first output shaft (512) and the second output shaft (513) to rotate via the input shaft (511). The first drive cam (52) is mounted on the shaft end of the first output shaft (512), and the second drive cam (53) is mounted on the shaft end of the second output shaft (513).

5. The rotor radial excitation simulation device with adjustable vortex amplitude and frequency as claimed in claim 4, characterized in that: A displacement sensor group (8) is also fixed on the lower base plate seat (61), and the displacement sensor group (8) is in contact with the excitation shaft (2) and is used to monitor the axis trajectory of the excitation shaft (2).

6. The rotor radial excitation simulation device with adjustable vortex amplitude and frequency according to claim 5, characterized in that: An axial limiting disc (21) is provided on the excitation shaft (2) between the drive disc assembly (3) and the test seal module (1). The axial limiting disc (21) limits the axial position of the excitation shaft (2) by contacting with a ball pin assembly (54) fixed on the gear box (51), thereby preventing the generation of small axial displacement.

7. The rotor radial excitation simulation device with adjustable vortex amplitude and frequency according to claim 6, characterized in that: A slide rail (9) is further provided on the lower base plate seat (61), and the slide rail (9) is located outside the gear box (51). A transparent protective cover (63) is provided on each side of the slide rail (9). The transparent protective cover (63) moves along the slide rail (9) to protect the rotor radial excitation simulation device.

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