A loading device for dynamic performance test of permanent magnetic thrust bearing and a design method thereof

Abstract

The application provides a loading device for dynamic performance test of a permanent magnetic thrust bearing and a design method thereof, and belongs to the technical field of permanent magnetic thrust bearing detection. The loading device comprises a permanent magnetic thrust bearing end flange plate, a gasket, a cross roller bearing, a sensor flange plate, a spoke type force sensor, a loading cantilever beam, a power sensor, a thrust loading device, a exciting force loading device and an eddy current displacement sensor. The application discloses a design method of a loading device for dynamic performance test of a permanent magnetic thrust bearing, and can meet the loading demand of dynamic performance test of the permanent magnetic thrust bearing, aiming at the problems that a hydraulic cylinder and an exciter cannot directly load the load to the rotating end face, and two independent loading devices cannot be directly loaded to the same end face.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of permanent magnetic thrust bearing detection, and relates to a loading device, in particular to a loading device for dynamic performance test of a permanent magnetic thrust bearing and a design method thereof. BACKGROUND

[0002] With the gradual development of magnetic technology, the application of magnetic bearings in the engineering field is continuously deepened. As an important part of mechanical equipment, the permanent magnetic thrust bearing can realize mechanical contact-free through the interaction of magnetic fields, and has a broad prospect in the application of mechanical equipment. The dynamic performance of the permanent magnetic thrust bearing, i.e. the bearing dynamic stiffness, is a key evaluation parameter of the magnetic bearing. Research on the dynamic stiffness of the permanent magnetic thrust bearing has a profound influence on the improvement of the performance of the magnetic bearing, and is an unavoidable research focus of the permanent magnetic thrust bearing. The dynamic performance test of the permanent magnetic thrust bearing is essentially that the magnetic bearing is subjected to the superposition of static thrust and excitation force under different rotating speeds, the axial force and axial displacement are collected to calculate the dynamic stiffness, and then the dynamic stiffness-frequency curve is formed. In the experiment, the loading device is a hydraulic cylinder and an exciter, but the hydraulic cylinder and the exciter can only be loaded on the static end face, while the measured object needs to rotate under the driving of the motor, so the load cannot be directly loaded on the rotating end face.

[0003] At present, the related research content of the permanent magnetic thrust bearing is relatively novel, and the research on its performance parameters has not yet formed a complete experimental scheme system, so the research and design of the equipment for dynamic performance test of the permanent magnetic thrust bearing are relatively less. In view of the demand of university scientific research projects, the application provides a design method of a loading device for dynamic performance test of a permanent magnetic thrust bearing. SUMMARY

[0004] The application aims at the problem that the hydraulic cylinder and the exciter cannot directly load the load on the rotating end face, and the two independent loading devices cannot be directly loaded on the same end face, and provides a design method of a loading device for dynamic performance test of a permanent magnetic thrust bearing to meet the loading demand of the dynamic performance test of the permanent magnetic thrust bearing. Through the design of the loading mechanism, the hydraulic cylinder and the exciter can uniformly load the load on the rotating end face, and complete the load loading for the dynamic performance test of the permanent magnetic thrust bearing.

[0005] In order to achieve the above purpose, the application adopts the following technical scheme:

[0006] The utility model relates to a kind of loading device for permanent magnet thrust bearing dynamic performance test, the loading device comprising permanent magnet thrust bearing end flange plate 1, washer 2, crossed roller bearing 3, sensor side flange plate 4, spoke force sensor 5, loading cantilever beam 7, power sensor 8, thrust loading device 6, exciting force loading device 9, eddy current displacement sensor 11 group consisting of main structural member, and by displacement sensor support 12, crossed roller bearing outer ring nut 13, crossed roller bearing outer ring bolt 14, washer 15 for sensor side flange plate, bolt 16 for sensor side flange plate, crossed roller bearing inner ring screw 17, nut 18 for sensor side flange plate consisting of auxiliary components.

[0007] The permanent magnet thrust bearing end flange plate 1 is the permanent magnet thrust bearing output interface, is installed in crossed roller bearing 3 dynamic side;The size of permanent magnet thrust bearing end flange plate 1 is determined by the size of permanent magnet thrust bearing.

[0008] The washer 2 is placed between crossed roller bearing 3 and permanent magnet thrust bearing end flange plate 1;The inner diameter and outer diameter of washer 2 are matched with the inner diameter and outer diameter of crossed roller bearing outer ring respectively;Washer 2 separates the non-rotating inner ring part of crossed roller bearing 3 and rotating permanent magnet thrust bearing end flange plate 1, and provides non-rotating loading end surface for loading equipment;Crossed roller bearing 3, washer 2 and permanent magnet thrust bearing end flange plate 1 are concentrically installed, and crossed roller bearing outer ring bolt 14 passes through crossed roller bearing 3, washer 2 and permanent magnet thrust bearing end flange plate 1 in sequence, and crossed roller bearing outer ring nut 13 is matched using double-nut type.

[0009] The crossed roller bearing 3 includes inner ring and outer ring, and the two are connected by crossed roller contact;The inner ring part of crossed roller bearing 3 is connected with sensor side flange plate 4 by screw, and is non-rotating part;The outer ring part of crossed roller bearing 3 is connected with permanent magnet thrust bearing end flange plate by bolt and nut, and is rotating part.

[0010] The sensor side flange plate 4 is a core component of the device, and the structure of the sensor side flange plate 4 is a convex flange plate. A circular mounting groove with the same diameter as the outer diameter of the spoke force sensor is formed in the mounting position of the spoke force sensor. The sensor side flange plate 4 is connected to the inner ring part of the cross roller bearing, and the sensor side flange plate 4 is connected to the inner ring part of the cross roller bearing 3 through the cooperation of the cross roller bearing inner ring screw 17 and the cross roller bearing inner ring thread. The other function of the sensor side flange plate 4 is to provide a mounting space for the spoke force sensor 5 at the static end face. The spoke force sensor 5 is mounted in the mounting groove of the sensor side flange plate. The sensor side flange plate is fixed on one side of the loading cantilever beam 7 by using the sensor side flange plate bolt 16, the sensor side flange plate washer 15 and the sensor side flange plate nut 18. The sensor side flange plate nut 18 is installed with double nut anti-loose, which realizes the fixation of the sensor side flange plate 4, the spoke force sensor 5 and the loading cantilever beam 7. The flange plate of the sensor side flange plate 4 also serves as the measurement plane of the eddy current displacement sensor 11. The outer diameter of the flange plate is designed according to the outer shape size of the eddy current displacement sensor 11.

[0011] The loading cantilever beam 7 is another core component of the device, which is designed by integrating the flange plate boss and the cantilever beam. The boss structure of the flange plate is a cylinder, and the center axis of the boss is collinear with the center axis of the flange plate. The flange plate boss is manufactured by casting process. The cantilever beam is connected to the boss by welding. The center axis of the threaded hole on the outer side of the cantilever beam is required to be in the same plane as the axis of the boss. The flange plate in the flange plate boss is used to fix the spoke force sensor, and its size is designed according to the size of the spoke force sensor. The cantilever beam, the power sensor 8 and the excitation force loading device 9 of the loading cantilever beam 7 are connected in sequence by threads. During the experiment, the thrust loading device 6 is extended by the push rod and pressed at the center of the flange plate boss of the cantilever beam 7, thereby loading the axial static load of the permanent magnet thrust bearing. The excitation force loading device 9 is connected to the power sensor 8 through threads. The threads of the power sensor 8 are matched with the threaded mounting holes of the loading cantilever beam 7, thereby realizing the connection of the excitation force loading device 9, the power sensor 8 and the loading cantilever beam 7. The load of the excitation force loading device 9 is loaded to the center axis of the flange plate of the cantilever beam 7, thereby completing the excitation force loading of the permanent magnet thrust bearing along the axial direction.

[0012] The thrust loading device 6 and the excitation force loading device 9 are installed on the predetermined mounting platform through the support 10.

[0013] The eddy current displacement sensor 11 is installed on a predetermined mounting platform by a displacement sensor support 12. The displacement sensor adopts a non-contact measurement method. The sensor probe is separated from the sensor flange 4 by a certain distance. The sensor probe generates an electromagnetic field by a small coil. The surface of the measured object generates an induced current when it is close to the sensor probe, and then generates an opposite electromagnetic field. The distance between the sensor and the measured object is calculated according to the strength of the opposite electromagnetic field, and the axial displacement measurement is completed.

[0014] The spoke force sensor 5 is installed between the sensor flange 4 and the loading cantilever beam 7. The rigidity of the sensor device itself supports it as part of the shaft, and the axial force value is collected in the pressure. The spoke force sensor 5 deforms under external force through an elastomer element, causing the resistance strain gauge to also deform, resulting in a change in resistance value. The strain is converted into an electrical signal, the external force is converted into an electrical signal, and the axial force measurement is completed.

[0015] Further, the excitation force loading device 9 includes an exciter, a power amplifier, a signal generator, and an online charge converter. The exciter amplitude and excitation frequency need to be selected according to the actual simulation scenario.

[0016] Further, the power sensor 8 is connected in series with the loading cantilever beam 7 and the excitation force loading device 9, and does not bear static load during the test.

[0017] Further, the sensor flange is provided with a washer 15 as a lock washer. This component is used in cooperation with a sensor flange bolt 16, a sensor flange washer 15, and a sensor flange nut 18. The exciter device in the device generates a vibration signal. When the sensor flange bolt 16 loosens, the washer generates a lifting force through the relative movement of its own structure, thereby preventing loosening.

[0018] A design method for a permanent magnet thrust bearing dynamic performance test loading device, the design method includes cross-roller bearing, spoke force sensor, power sensor selection, component design, and determination of thrust loading device and excitation force loading device, and then completes the design of the loading device structure. The design method is suitable for dynamic performance testing of permanent magnet thrust bearings of various sizes. The specific method is as follows:

[0019] (a) Select the size of the cross-roller bearing

[0020] Determine the rated load F of the cross-roller bearing according to the maximum axial static thrust of the permanent magnet thrust bearing 额 :

[0021] F 额 = a x F max

[0022] Where Fmax The maximum value of the axial static thrust is tested for the dynamic performance of the permanent magnetic thrust bearing; a is the safety factor of the cross roller bearing, since the cross roller bearing is the core component of the equipment, the running safety thereof needs to be considered, and the value range of a is 1.5-2.5.

[0023] According to the rated load F of the cross roller bearing 额 , the size of the cross roller bearing is selected, and then the hole number N of the outer ring of the cross roller bearing 交叉 and the mounting hole size D of the inner ring of the corresponding cross roller bearing 交叉 are determined.

[0024] (b) checking the bolt strength of the outer ring of the cross roller bearing

[0025] In the application, the gaskets 2 are respectively attached to the permanent magnetic thrust end flange plate 1 and the outer ring part of the cross roller bearing 3, the gasket hole number N 垫 , the gasket outer diameter D w :

[0026] N 垫 =N 法兰盘 =N 交叉

[0027] D w =D 法兰盘 =D 交叉

[0028] Wherein, N 法兰盘 , D 法兰盘 , N 交叉 , D 交叉 are respectively the hole number and the mounting hole size of the permanent magnetic thrust bearing end flange plate, the hole number and the mounting hole size of the outer ring of the cross roller bearing, and the size depends on the selection of the cross roller bearing. The strength of the outer ring bolt 14 of the cross roller bearing is checked, and the analytical method is used for calculation:

[0029] The hinge hole is used to fix the permanent magnetic thrust bearing end flange plate 1, the gasket 2 and the outer ring bolt 14 of the cross roller bearing. The assembly mode relies on bolt shearing and bolt and hole wall extrusion to resist torque. The maximum shearing force F smax of the outer ring bolt 14 of the cross roller bearing is:

[0030]

[0031] Wherein, T represents the torque transmitted from the permanent magnetic thrust bearing end flange plate; r max represents the maximum distance from the axis of the bolt to the symmetric center axis of the bolt group; z represents the number of bolts in the bolt group; r j represents the distance from the axis of the jth bolt to the symmetric center axis of the bolt group.

[0032] The shear strength τ of the cross roller bearing outer ring bolt 14 is checked:

[0033]

[0034] Wherein: i is the number of shear planes of the cross roller bearing outer ring bolt rod 14; d0 is the diameter of the shear plane of the cross roller bearing outer ring bolt 14; [τ] is the allowable shear force of the alloy steel material; [σ] is the allowable tensile stress of the alloy steel material.

[0035] The extrusion strength σ of the cross roller bearing outer ring bolt 14 is checked: jy

[0036]

[0037] Wherein: L min is the minimum height of the extrusion surface of the cross roller bearing outer ring bolt rod 14 and the hole wall of the cross roller bearing outer ring mounting hole, and in actual use, L min ≥1.25d, wherein d represents the diameter of the cross roller bearing outer ring bolt rod 14.

[0038] (c) Design the sensor side flange plate

[0039] In the present application, the sensor side flange plate 4 is used to connect the spoke force sensor 5 and the cross roller bearing 3 respectively, and serves as the measurement plane of the eddy current displacement sensor 11. The diameter d 法兰盘 of the sensor side flange plate 4 needs to meet:

[0040] d 法兰盘 ≥L 位移 +d 位移

[0041] Wherein, d 法兰盘 is the distance between the center axis of the eddy current displacement sensor 11 and the center axis of the sensor flange plate 4; d 位移 is the maximum diameter of the eddy current displacement sensor 11.

[0042] The structure strength of the sensor side flange plate 4 component is checked separately by using the finite element analysis method. The contact surface of the sensor side flange plate 4 and the cross roller bearing inner ring screw 17 is defined as a fixed boundary, and the axial load is uniformly loaded on the spoke force sensor mounting end face. In the finite element analysis result, the yield strength σ s of the sensor side flange plate 4 needs to meet:

[0043] σ s ≤[σ s ]

[0044] Wherein, [σ s ] is the material yield strength. ​

[0045] (d) selecting a thrust loading device and an exciting force loading device

[0046] In the present application, the axial maximum thrust of the thrust loading device 6 is determined according to the axial maximum bearing capacity of the permanent magnetic thrust bearing; the maximum amplitude F of the exciting force of the exciting force loading device 9 d The following conditions need to be met:

[0047]

[0048] Wherein, F s is the axial maximum thrust of the thrust loading device 6.

[0049] (e) designing a loading cantilever beam

[0050] In the present application, the loading cantilever beam 7 is composed of a flange plate and a cantilever beam. The length L of the cantilever beam f The following conditions need to be met:

[0051]

[0052] Wherein, d 静载 is the width of the thrust loading device 6; d 激振力 is the width of the exciting force loading device 9.

[0053] During operation, the center of the flange plate of the loading cantilever beam 7 is subjected to static thrust, and the center of the cantilever beam is subjected to exciting force. The structural strength of the loading cantilever beam 7 is checked separately by using finite element analysis. In the finite element analysis, the axial static load is uniformly loaded on the center plane of the flange plate; the alternating load is loaded on the bottom surface of the threaded mounting hole of the cantilever beam; the inner wall of the mounting hole of the loading cantilever beam 7 is defined as a fixed boundary. The yield strength σ f The following conditions need to be met:

[0054] σ f ≤ [σ s ]

[0055] Wherein, [σ s ] is the material yield strength.

[0056] The beneficial effects of the present application are:

[0057] The present application is aimed at the problem that the hydraulic cylinder and the exciter cannot directly load the load to the rotating end face, and the two independent loading devices cannot be directly loaded to the same end face. The dynamic and static end faces are separated by the crossed roller bearing and the sensor side flange plate, and the axial static thrust and the exciting force are both loaded to the axis center by the loading end flange plate. The load of the thrust loading device and the exciter is uniformly loaded to the rotating end face by the loading mechanism designed in the present application, and the dynamic load loading of the permanent magnetic thrust bearing is realized. BRIEF DESCRIPTION OF DRAWINGS

[0058] Figure 1 Figure 1 is a schematic diagram of the overall structure of a loading device for dynamic performance testing of a permanent magnetic thrust bearing;

[0059] Figure 2 Figure 2 is a side view of the overall structure of a loading device for dynamic performance testing of a permanent magnetic thrust bearing;

[0060] Figure 3 Figure 3 is a top view of the overall structure of a loading device for dynamic performance testing of a permanent magnetic thrust bearing;

[0061] Figure 4 Figure 4 is an exploded view of the cross-roller bearing of the present application;

[0062] Figure 5 Figure 5 is a sectional view of the cross-roller bearing of the present application;

[0063] Figure 6 Figure 6 is an exploded view of the sensor flange and loading cantilever beam of the present application;

[0064] Figure 7 Figure 7 is a sectional view of the sensor flange and loading cantilever beam of the present application;

[0065] Figure 8 Figure 8 is a finite element analysis result diagram of the sensor flange of the present application;

[0066] Figure 9 Figure 9 is a finite element analysis result diagram of the loading cantilever beam of the present application.

[0067] In the figure: 1 permanent magnetic thrust bearing end flange; 2 gasket; 3 cross-roller bearing; 4 sensor side flange; 5 spoke force sensor; 6 thrust loading device; 7 loading cantilever beam; 8 dynamic force sensor; 9 exciting force loading device; 10 support; 11 eddy current displacement sensor; 12 displacement sensor support; 13 cross-roller bearing outer ring nut; 14 cross-roller bearing outer ring bolt; 15 gasket for sensor side flange; 16 bolt for sensor side flange; 17 cross-roller bearing inner ring screw; 18 nut for sensor side flange. DETAILED DESCRIPTION

[0068] The specific embodiments of the present application are described in further detail below in conjunction with the accompanying drawings. The following examples or drawings are used to illustrate the present application, but are not used to limit the scope of the present application.

[0069] As shown in the accompanying drawings Figure 1A loading device for dynamic performance test of permanent magnetic thrust bearing, the loading device comprises a permanent magnetic thrust bearing end flange plate 1, a gasket 2, a cross roller bearing 3, a sensor side flange plate 4, a spoke force sensor 5, a loading cantilever beam 7, a power sensor 8, a thrust loading device 6, a exciting force loading device 9, an eddy current displacement sensor 11, and auxiliary components including a displacement sensor support 12, a cross roller bearing outer ring nut 13, a cross roller bearing outer ring bolt 14, a gasket for sensor side flange plate 15, a bolt for sensor side flange plate 16, a cross roller bearing inner ring screw 17, and a nut for sensor side flange plate 18.

[0070] As shown in the accompanying drawings Figure 2 The permanent magnetic thrust bearing end flange plate 1 is an output interface of the permanent magnetic thrust bearing and is installed on the dynamic side of the cross roller bearing 3.

[0071] As shown in the accompanying drawings Figure 3 The gasket 2 is placed between the cross roller bearing 3 and the permanent magnetic thrust bearing end flange plate 1, the inner diameter and the outer diameter of the gasket 2 are matched with the inner diameter and the outer diameter of the outer ring of the cross roller bearing respectively, the gasket 2 separates the non-rotating inner ring part of the cross roller bearing 3 from the rotating permanent magnetic thrust bearing end flange plate 1, and provides a non-rotating loading end surface for the loading device, the cross roller bearing 3, the gasket 2 and the permanent magnetic thrust bearing end flange plate 1 are concentrically installed, the cross roller bearing outer ring bolt 14 passes through the cross roller bearing 3, the gasket 2 and the permanent magnetic thrust bearing end flange plate 1 in sequence, and the cross roller bearing outer ring nut 13 is matched in a double nut type.

[0072] As shown in the accompanying drawings Figure 4 The cross roller bearing 3 comprises an inner ring and an outer ring which are connected through cross roller contact, the inner ring part of the cross roller bearing 3 is connected with the sensor side flange plate 4 through a screw and is a non-rotating part, and the outer ring part of the cross roller bearing 3 is connected with the permanent magnetic thrust bearing end flange plate through a bolt and a nut and is a rotating part.

[0073] As shown in the accompanying drawings Figure 5, the sensor side flange plate 4 is the core component of the device, the structure of the sensor side flange plate 4 is convex flange plate, and the component is processed with circular mounting groove with the same outer diameter size of the spoke type force sensor at the installation position of the spoke type force sensor. The sensor side flange plate 4 is connected with the inner ring part of the cross roller bearing, and the sensor side flange plate 4 is connected with the inner ring part of the cross roller bearing 3 through the cooperation of the cross roller bearing inner ring screw 17 and the cross roller bearing inner ring thread; another function of the sensor side flange plate 4 is to provide installation space for the spoke type force sensor 5 at the static end face, and the spoke type force sensor 5 is installed in the mounting groove of the sensor side flange plate, and the sensor side flange plate is fixed on one side of the loading cantilever beam 7 by using the sensor side flange plate bolt 16, the sensor side flange plate washer 15 and the sensor side flange plate nut 18, the sensor side flange plate nut 18 is installed by using double nut anti-loose, and the sensor side flange plate 4, the spoke type force sensor 5 and the loading cantilever beam 7 are fixed; the flange plate of the sensor side flange plate 4 also needs to serve as the measurement plane of the eddy current displacement sensor 11, and the outer diameter of the flange plate is designed according to the outer shape size of the eddy current displacement sensor 11;

[0074] As shown in the accompanying drawings Figure 6 , the loading cantilever beam 7 is another core component of the device, which is designed in an integrated manner of flange plate boss and cantilever beam. The boss structure of the flange plate is a cylinder, the center axis of the boss is collinear with the center axis of the flange plate, and the flange plate boss is manufactured by casting process; the cantilever beam is connected with the boss by welding, and the center axis of the threaded hole on the outer side of the cantilever beam is required to be coplanar with the axis of the boss; the flange plate in the flange plate boss is used to fix the spoke type force sensor, and the size is designed according to the size of the spoke type force sensor. As shown in the accompanying drawings Figure 7 , the cantilever beam, the power sensor 8 and the excitation force loading device 9 of the loading cantilever beam 7 are connected in sequence through threads; in the experiment, the thrust loading device 6 is elongated through the push rod and is pressed at the center of the flange plate boss of the cantilever beam 7, so as to load the axial static load of the permanent magnet thrust bearing; the excitation force loading device 9 is connected with the power sensor 8 through threads, the threads of the power sensor 8 are matched with the threaded mounting holes of the loading cantilever beam 7, the excitation force loading device 9, the power sensor 8 and the loading cantilever beam 7 are connected, and then the load of the excitation force loading device 9 is loaded to the center axis of the flange plate of the cantilever beam 7, so as to complete the excitation force loading of the permanent magnet thrust bearing along the axial direction;

[0075] The thrust loading device 6 and the excitation force loading device 9 are installed on the predetermined installation platform through the support 10;

[0076] The eddy current displacement sensor 11 is installed on a predetermined mounting platform through a displacement sensor support 12, and adopts a non-contact measurement mode. The sensor probe is separated from the sensor flange 4 by a certain distance, and generates an electromagnetic field through a small coil. The surface of the measured object to be approached generates an induced current, and further generates a reverse electromagnetic field. The distance between the sensor and the measured object is calculated according to the strength of the reverse electromagnetic field, and the axial displacement measurement is completed.

[0077] The spoke force sensor 5 is installed between the sensor flange 4 and the loading cantilever beam 7. The rigidity of the sensor device itself supports it as part of the shaft, and collects the axial force value in the pressure. The spoke force sensor 5 deforms under external force through an elastomer element, so that the resistance strain gauge also deforms, resulting in a change in resistance value. The strain is converted into an electric signal, the external force is converted into an electric signal, and the axial force measurement is completed.

[0078] Further, the excitation force loading device 9 includes an exciter, a power amplifier, a signal generator, and an online charge converter. The exciter amplitude and excitation frequency need to be selected according to the actual simulation scenario.

[0079] Further, the power sensor 8 is connected in series with the loading cantilever beam 7 and the excitation force loading device 9, and does not bear static load during the test.

[0080] Further, the sensor flange is provided with a washer 15 as a lock washer. This component is used in cooperation with a sensor flange bolt 16, a sensor flange washer 15, and a sensor flange nut 18. The exciter device in the device produces a vibration signal. When the sensor flange bolt 16 loosens, the washer produces a lifting force through the relative movement of its own structure, thereby preventing loosening.

[0081] (a) Select the size of the cross-roller bearing

[0082] According to the maximum axial static thrust of the permanent magnet thrust bearing, the rated load F of the cross-roller bearing is determined 额 . Wherein, F max is the maximum value of the axial static thrust of the dynamic performance test of the permanent magnet thrust bearing, and a is the safety factor. Combined with the basic parameters of the permanent magnet thrust bearing, the maximum value of the axial force of the permanent magnet thrust bearing is 2.5kN, and the safety factor is 2.

[0083] F 额 = a x F max = 2 x 2.5kN = 5kN

[0084] Based on the cross roller bearing selection manual, the basic dimensional parameters of the cross roller bearing are determined. The basic outer ring dimension of the cross roller bearing is D = 70mm, and the hole size on the outer ring is 6-Φ3.4 through hole; the mounting hole on the inner ring is 6-M3, and the corresponding mounting hole size is 28mm.

[0085] (b) Check the bolt strength of the outer ring of the crossed roller bearing.

[0086] The washers are respectively fitted to the permanent magnet thrust end flange and the outer ring of the crossed roller bearing, and the number of holes N of the outer ring of the crossed roller bearing is... 垫 Dimension D of the outer ring mounting hole for the crossed roller bearing w :

[0087] N 垫 =N 法兰盘 =N 交叉 =6

[0088] D w =D 法兰盘 =D 交叉 =57mm

[0089] Where: N 法兰盘 D 法兰盘 N 交叉 D 交叉 These figures represent the number of holes and mounting hole dimensions on the end flange of the permanent magnet thrust bearing, and the number of holes and mounting hole dimensions on the outer ring of the crossed roller bearing. These dimensions depend on the selection of the crossed roller bearing. Strength verification is performed on bolt 14 of the outer ring of the crossed roller bearing using analytical calculations.

[0090] The permanent magnet thrust bearing end flange 1, washer 2, and crossed roller bearing outer ring bolt 14 are fixed using a reamed-hole method. This assembly method relies on bolt shearing and bolt compression against the hole wall to resist torque. The torque experienced by this equipment depends on the permanent magnet thrust bearing motor drive end. In this embodiment, the torque T transmitted by the permanent magnet thrust bearing end flange is 77 N·m. max The maximum distance r from the bolt axis to the axis of symmetry of the bolt group max The diameter is 28.5mm; the number of bolts in the bolt group is 6; the distance r from the axis of each bolt to the axis of symmetry of the bolt group is... j It is 28.5mm;

[0091]

[0092] The shear strength τ of bolt 14 on the outer ring of the crossed roller bearing is checked:

[0093]

[0094] Wherein: i is the number of cross-roller bearing outer ring bolt rod 14 shear plane; d0 is the cross-roller bearing outer ring bolt rod 14 shear plane diameter; [τ] is the allowable shear force of alloy steel material; [σ] is the allowable tensile stress of alloy steel material. Combined with the attached Figure 5 , the bolt shear plane is 1, and the bolt shear plane diameter is 3mm. In this embodiment, a 12.9 grade high-strength bolt is selected, and the allowable tensile stress of the alloy steel material [σ] is 1220MPa. The checking calculation is performed:

[0095]

[0096] 0.0638MPa≤[τ]=(0.75~0.8)[σ]

[0097] Conclusion, the shear strength of the cross-roller bearing outer ring bolt 14 is qualified.

[0098] The bolt at this position is subjected to extrusion force, and the extrusion strength σ jy of the bolt is checked:

[0099]

[0100] Wherein: L min is the minimum height of the extrusion surface of the bolt rod and the hole wall, and in actual use, L min ≥1.25d, and in this embodiment, L min is taken as 6mm. The checking calculation is performed:

[0101]

[0102] 25.01MPa≤[σ] p =(1.7~2.0)[σ]

[0103] Conclusion, the extrusion strength of the cross-roller bearing outer ring bolt 14 is qualified.

[0104] (c) Design the sensor side flange

[0105] In the present application, the sensor side flange 4 is used to connect the spoke force sensor 5 and the cross-roller bearing 3 respectively, and serves as the measurement plane of the eddy current displacement sensor 11. The diameter d 法兰盘 of the sensor side flange 4 needs to meet:

[0106] d 法兰盘 ≥L 位移 +d 位移

[0107] Wherein, d 法兰盘 is the distance between the center axis of the eddy current displacement sensor 11 and the center axis of the sensor flange 4; d 位移is the maximum diameter of the eddy current displacement sensor 11. In this embodiment, the axial displacement of the permanent magnetic thrust bearing is designed to be 8mm, and the eddy current displacement sensor with a range of 10mm is selected. The size d 位移 is 35mm. In this embodiment, L 位移 is 65mm. Therefore, d 法兰盘 is 110mm.

[0108] In this embodiment, the material is 45 steel, the contact surface between the sensor flange 4 and the inner ring screw 17 of the cross roller bearing is defined as a fixed boundary, the axial load is 3kN, and the axial load is uniformly loaded on the spoke type force sensor mounting end face. As shown in FIG. 8, the maximum stress σ Figure 8 of the sensor flange 4 in the finite element analysis result is 35.842MPa. w The following conditions need to be met:

[0109] σ s ≤[σ s ]

[0110] In this embodiment, the component is made of 45 steel, and the yield strength [σ s ] of the material is 355Mpa. The finite element analysis result is shown in FIG. 8. Figure 8 According to the result, the overall stress of the sensor flange 4 in this embodiment is uniform, the stress is mainly concentrated on the contact surface between the sensor flange 4 and the inner ring of the cross roller bearing 3, and the maximum stress is concentrated on the edge of the threaded hole of the sensor flange 4. The result shows that σ s max is 35.842MPa:

[0111] σ s = 35.842MPa ≤ [σ]

[0112] In conclusion, the strength of the sensor flange 4 meets the requirements.

[0113] (d) Selecting a thrust loading device and a vibration excitation force loading device

[0114] In this application, the axial maximum thrust of the thrust loading device 6 is determined according to the axial maximum bearing capacity of the permanent magnetic thrust bearing, and the maximum amplitude F d of the vibration excitation force of the vibration excitation force loading device 9 needs to meet the following conditions:

[0115]

[0116] Wherein, F s is the axial maximum thrust of the thrust loading device 6. In this embodiment, the rated axial thrust of the permanent magnetic thrust bearing is 2.5kN, and the maximum thrust F sThe static thrust is 3kN, and the maximum amplitude of the exciting force loading device is 100N.

[0117] (e) Designing the loading cantilever beam

[0118] In the present application, the loading cantilever beam 7 is combined by a flange plate and a cantilever beam. The length L of the cantilever beam is 205mm. f The following conditions are met:

[0119]

[0120] Wherein, d 静载 is the width of the thrust loading device 6; d 激振力 is the width of the exciting force loading device 9. In the present embodiment, d 静载 150, d 激振力 is 80mm. According to the above formula, L f is 205mm.

[0121] During operation, the center of the flange plate of the loading cantilever beam 7 is subjected to a static thrust, and the center of the cantilever beam is subjected to an exciting force. The structural strength of the loading cantilever beam 7 is checked separately by using finite element analysis. In the present embodiment, the material is 45 steel; in the finite element analysis, the axial static load of 3kN is uniformly loaded on the center plane of the flange plate, and the alternating load is loaded on the bottom surface of the mounting hole of the cantilever beam, with an amplitude of 100N; the inner wall of the mounting hole of the loading cantilever beam is set as a fixed boundary. In the present embodiment, the component is made of 45 steel, and the yield strength [σ s ] of the material is 355Mpa. The finite element analysis results are shown in the attached figures. Figure 9 According to the results, the stress distribution of the overall structure of the loading cantilever beam is relatively uniform; the stress of the junction between the cantilever beam part of the loading cantilever beam and the boss structure is relatively large, about 8.73Mpa; the stress at the junction between the boss structure of the loading cantilever beam and the flange plate is relatively large, about 11.649Mpa; the stress at the edge of the mounting hole of the flange plate of the loading cantilever beam is relatively large, and this part is the position with the largest stress in the analysis results, and the results show that the maximum σ f is 26.209MPa:

[0122] σ f ≤[σ]

[0123] Conclusion, the strength of the loading cantilever beam 7 meets the requirements.

[0124] The above description is only a specific embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A loading device for dynamic performance testing of permanent magnetic thrust bearing, characterized in that, The loading device comprises a main structure and auxiliary components, the main structure comprises a permanent magnetic thrust bearing end flange (1), a gasket (2), a crossed roller bearing (3), a sensor side flange (4), a spoke force sensor (5), a loading cantilever beam (7), a power sensor (8), a thrust loading device (6), a exciting force loading device (9), and an eddy current displacement sensor (11), and the auxiliary components comprise a displacement sensor support (12); The permanent magnetic thrust bearing end flange (1) is a permanent magnetic thrust bearing output interface, and is installed on the dynamic side of the crossed roller bearing (3); the size of the permanent magnetic thrust bearing end flange (1) is determined by the size of the permanent magnetic thrust bearing; The gasket (2) is arranged between the crossed roller bearing (3) and the permanent magnetic thrust bearing end flange (1), and provides a non-rotating loading end surface for the loading device; the gasket (2) is matched with the outer ring of the crossed roller bearing; The crossed roller bearing (3) comprises an inner ring and an outer ring, and the two are connected through crossed roller contact; the inner ring part is connected with the sensor side flange (4), and is a non-rotating part; The outer ring part is connected with the permanent magnetic thrust bearing end flange (1), and is a rotating part; The sensor side flange (4) is a convex flange, and a circular mounting groove with the same size as the outer diameter of the spoke force sensor is processed at the mounting position of the spoke force sensor; the sensor side flange (4) is connected with the inner ring part of the static crossed roller bearing (3), and provides a mounting space for the spoke force sensor (5) at the static end surface, and is mounted in cooperation with the flange boss end of the loading cantilever beam (7); the flange of the sensor side flange (4) is a measurement plane of the eddy current displacement sensor (11), and the outer diameter of the flange is designed according to the size of the eddy current displacement sensor (11); The loading cantilever beam (7) is designed in an integrated manner of a flange boss and a cantilever beam; the flange boss is a cylinder, and the center axis of the flange boss is collinear with the center axis of the flange; the center axis of the threaded hole on the side of the cantilever beam away from the flange boss is in the same plane as the center axis of the flange boss; the flange in the flange boss is used for fixing the spoke force sensor (5); the cantilever beam, the power sensor (8) and the exciting force loading device (9) of the loading cantilever beam (7) are connected in sequence, and do not bear static load during testing; during use, the thrust loading device (6) is pressed at the center of the flange boss of the cantilever beam (7), so as to load the axial static load of the permanent magnetic thrust bearing; the load of the exciting force loading device (9) is loaded to the center axis of the flange boss through the power sensor (8) and the cantilever beam, so as to complete the exciting force loading of the permanent magnetic thrust bearing along the axial direction; The bottom of the thrust loading device (6) and the exciting force loading device (9) is installed on a predetermined mounting platform through a support (10); The eddy current displacement sensor (11) is installed on a predetermined installation platform through a displacement sensor support (12), the displacement sensor (11) adopts non-contact measurement, the sensor probe is not in contact with the surface of the sensor side flange plate (4), the sensor probe generates an electromagnetic field, the surface of the measured object generates an induced current, and then generates a reverse electromagnetic field, the distance between the displacement sensor (11) and the measured object is calculated according to the strength of the reverse electromagnetic field, and the axial displacement measurement is completed. The spoke force sensor (5) is installed between the sensor side flange plate (4) and the flange boss of the loading cantilever beam (7), and the axial force value is collected in the pressure.

2. The loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 1, characterized in that, The cross roller bearing (3), the washer (2) and the permanent magnetic thrust bearing end flange plate (1) are concentrically installed, the cross roller bearing outer ring bolt (14) passes through the cross roller bearing (3), the washer (2) and the permanent magnetic thrust bearing end flange plate (1) in sequence, and is matched with the cross roller bearing outer ring nut (13) in a double-nut mode.

3. The loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 2, characterized in that, The sensor side flange plate (4) and the inner ring part of the cross roller bearing (3) are connected through the cooperation of the cross roller bearing inner ring screw (17) and the cross roller bearing inner ring thread.

4. The loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 3, characterized in that, The spoke force sensor (5) is installed in the installation groove of the sensor side flange plate (4), and is fixed on the side of the loading cantilever beam (7) through the sensor side flange plate bolt (16), the sensor side flange plate washer (15) and the sensor side flange plate nut (18), the sensor side flange plate nut (18) is installed in a double-nut anti-looseness mode, and the sensor side flange plate (4), the spoke force sensor (5) and the loading cantilever beam (7) are fixed.

5. The loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 4, characterized in that, The exciting force loading device (9) comprises an exciter, a power amplifier, a signal generator and an online charge converter; the exciter amplitude and the excitation frequency are selected according to the actual simulation scene.

6. The loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 5, characterized in that, The sensor side flange plate washer (15) is an anti-looseness washer, which is used in cooperation with the sensor side flange plate bolt (16) and the sensor side flange plate nut (18); the exciter device in the device generates a vibration signal, when the sensor side flange plate bolt (16) is loose, the washer generates a lifting force through the relative movement of its own structure, and the anti-looseness effect is achieved.

7. The design method of a loading device for dynamic performance test of permanent magnetic thrust bearing according to claim 6, characterized in that, The design method comprises the selection of the cross roller bearing, the spoke force sensor and the power sensor, the design of parts, the determination of the thrust loading device and the exciting force loading device, and the design of the loading device structure; the design method is suitable for dynamic performance testing of permanent magnetic thrust bearings of various sizes, and comprises the following steps: (a) selecting the size of the cross roller bearing; Determination of the rated load of a cross roller bearing from the axial maximum static thrust of a permanent magnetic thrust bearing : ； wherein, is the maximum value of the axial static thrust for the dynamic performance test of the permanent magnet thrust bearing; is the safety factor of the cross-roller bearing, is in the range of 1.5-2.5; According to the rated load of the crossed roller bearing Select the dimensions of the crossed roller bearing, and then determine the number of holes in the outer ring of the crossed roller bearing. and the mounting hole dimensions of the corresponding crossed roller bearing inner ring. ; (b) checking the bolt strength of the cross roller bearing outer ring; The washer (2) is respectively fitted to the outer ring of the permanent magnet thrust end flange (1) and the crossed roller bearing (3), and the number of its washer holes is as follows: Outer diameter of the washer as follows: ； Wherein: , , , are the number of holes and the size of the mounting holes of the end flange of the permanent magnetic thrust bearing, respectively, the number of holes and the size of the mounting holes of the outer ring of the crossed roller bearing, the size depending on the selection of the crossed roller bearing; The strength of the cross roller bearing outer ring bolt (14) is checked by using analytic method: the fixed permanent magnetic thrust bearing end flange (1), gasket (2) and cross roller bearing outer ring bolt (14) are made by reaming; the maximum shear force of the cross roller bearing outer ring bolt (14) is: : ； wherein, represents the torque transmitted from the permanent magnetic thrust bearing end flange; represents the maximum distance of the axis of the bolt to the axis of symmetry of the bolt set; z represents the number of bolts in the bolt set; represents the distance of the axis of the jth bolt to the axis of symmetry of the bolt set; Shear strength of cross roller bearing outer ring bolt (14) Verification is made: ； wherein: is the number of cross-roller bearing outer ring bolt (14) shear planes; is the cross-roller bearing outer ring bolt (14) shear plane diameter; is the allowable shear force for the alloy steel material; is the tensile allowable stress for the alloy steel material; Extrusion strength on cross roller bearing outer ring bolt (14) Verification is made: ； wherein: is the minimum height of the extrusion surface of the cross-roller bearing outer ring mounting hole wall for the cross-roller bearing outer ring bolt (14), and the minimum height of the extrusion surface of the cross-roller bearing outer ring mounting hole wall for the cross-roller bearing outer ring bolt (14) is 0.5d in actual use wherein d represents the diameter of the cross-roller bearing outer ring bolt (14); (c) designing the sensor side flange plate; The sensor-side flange (4) serves to connect the web-type force sensor (5) and the cross roller bearing (3), respectively, and as a measurement plane for the eddy current displacement sensor (11); the diameter of the sensor-side flange (4) The following must be fulfilled: ； wherein is the diameter of the sensor-side flange (4); is the maximum diameter of the eddy current displacement sensor (11); Adopt finite element analysis method, check the structure strength of sensor side flange (4) component alone; Define the contact surface of sensor side flange (4) and cross roller bearing inner ring screw (17) as fixed boundary, load the axial load evenly on the spoke type force sensor installation end surface; In the finite element analysis result, the yield strength of sensor side flange (4) Must satisfy: ； wherein, Ys is the yield strength of the material; (d) selecting the thrust loading device and the exciting force loading device; The thrust loading device (6) determines the axial maximum thrust of the thrust loading device (6) according to the axial maximum bearing capacity of the permanent magnetic thrust bearing; and the excitation force loading device (9) has the maximum amplitude of the excitation force The following conditions need to be met: ； wherein is the axial maximum thrust of the thrust loading device (6); (e) designing the loading cantilever beam The loading cantilever beam (7) is combined with the flange plate and the cantilever beam; the length of the cantilever beam Must meet: ； wherein is the width of the thrust loading device (6); is the width of the excitation force loading device (9); In the working process, the flange center of the cantilever beam (7) is subjected to static thrust, and the cantilever beam center is subjected to exciting force; the structural strength of the cantilever beam (7) is checked separately by using finite element analysis; in the finite element analysis, the axial static load is evenly loaded on the center plane of the flange; the alternating load is loaded on the bottom surface of the threaded mounting hole of the cantilever beam; the inner wall of the mounting hole of the cantilever beam (7) is defined as a fixed boundary; the yield strength of the cantilever beam is loaded The following conditions need to be met: ； wherein, is the yield strength of the material.

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