Resonance demonstration test bed for motor excitation mechanical system and method for verifying simulation result

Abstract

The invention provides a motor excitation mechanical system resonance demonstration test bench and a method for verifying a simulation result, and the test bench comprises a supporting member; the supporting piece is mounted on the bearing piece; the excitation vibration source for generating different vibration frequencies is mounted on the bearing part; small parts of a complex mechanical system are simplified into a proper mass block for counterweight, the mechanical system with a complex structure is simplified into a simple and reasonable system, the resonance phenomenon of the system is effectively displayed, a resonance interval is identified by adjusting the rotating speed of a motor, vibration parameters detected by a vibration meter are compared with a result obtained by simulation, and the vibration measurement accuracy is improved. The accuracy of a simulation result is verified, experimental verification support is provided for design and optimization of a large-scale mechanical system, and the problems that the structure of the large-scale mechanical system is complex, and the resonant frequency of the whole equipment is very difficult to find are solved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical system vibration and simulation prediction, and in particular to a motor-excited mechanical system resonance demonstration test bench and a method for verifying simulation results. Background Art

[0002] In mechanical engineering, when the natural frequency of the mechanical system structure coincides with the external excitation frequency, resonance will occur, causing the system to vibrate significantly. This phenomenon is an issue that must be focused on in the design of engineering machinery, because it may cause mechanical components to be subjected to stresses that exceed the design load-bearing capacity, resulting in structural damage. At the same time, resonance may significantly reduce the working efficiency of the mechanical system, affect the normal operation and production efficiency of the equipment, and even cause safety hazards. In addition, frequent vibration and structural damage will increase the frequency of equipment maintenance and repair, thereby increasing the operating cost of the equipment. Therefore, how to effectively avoid the resonance problem in the design stage is a key challenge in the design of complex mechanical systems.

[0003] However, large mechanical systems have complex structures and are extremely difficult to find the resonant frequency of the entire device due to the large number of components and their own natural frequencies. Traditional simulation calculations are difficult to accurately reflect the resonant characteristics of core components, which may cause the structure to deviate from reality, affecting the authenticity and reliability of simulation predictions.

[0004] Chinese patent CN118821522A shows a finite element simulation method, system, device and medium for wheel impact test. This technical solution mainly performs CAE simulation on the wheel impact test and cannot be directly extended to other types of mechanical vibration or resonance analysis. It mainly lacks experimental verification and cannot ensure the reliability of the simulation.

[0005] Patent CN221840745U shows a wheel modal test system for metal spring tires. This technical solution uses the method of suspending the tested object and testing it using the hammer method, but it cannot guarantee the stability of the tested object during testing. In addition, it can only perform free modal and constrained modal tests, and cannot achieve a comprehensive analysis of wheel vibration characteristics.

[0006] Patent CN109701856A shows a variable frequency controlled vibration excitation device. The technical solution has a limited scope of application. As long as it is for the vibration mixing of explosives, it is difficult to apply it to a wider range of mechanical system resonance research. In terms of accuracy, it can only explore the relationship between acceleration and frequency, which has certain limitations and may not be sufficient to meet the needs of high-precision resonance analysis of complex mechanical systems. In addition, the installation method of the variable frequency motor has high requirements.

[0007] Patent CN207337728U shows a bridge resonance simulation device. This technical solution is mainly used for bridge resonance simulation in specific scenarios, and it is difficult to adapt to the resonance phenomenon research of other complex structures. In addition, the vibration source transmits power through belt drive, which has weak power transmission accuracy and stability and is not very reliable. In view of the problems and defects existing in the above-mentioned patents, it is urgent to design a resonance experiment demonstration platform to solve the problems in the prior art that the experimental system has a single test type, cannot realize the resonance demonstration of complex equipment structures, and cannot compare the demonstration results with the simulation results. Summary of the invention

[0008] The purpose of the present invention is to address the deficiencies in the prior art and to provide a motor-excited mechanical system resonance demonstration test bench, which simplifies the small parts of a complex mechanical system into suitable mass blocks for counterweighting, simplifies a mechanical system with a complex structure into a simple and reasonable system, and uses the adjustment of the motor speed to identify the resonance range, effectively demonstrating the resonance phenomenon of the system, and uses a vibration meter to detect vibration parameters and compare them with the results obtained by simulation, thereby improving the accuracy of the simulation results, providing experimental verification support for the design and optimization of large-scale mechanical systems, and solving the problem that the structure of large-scale mechanical systems is relatively complex and it is extremely difficult to find the resonance frequency of the overall equipment.

[0009] To achieve the above object, the present invention provides the following technical solutions: A motor-excited mechanical system resonance demonstration test bench, characterized in that it also includes: Supports; A bearing member, the supporting member is mounted on the supporting member and is provided with a third adjusting slot; An excitation vibration source, the excitation vibration source generating different vibration frequencies is mounted on the bearing member, and the excitation vibration source is mounted on the third adjustment slot via a fastener; Change the different vibration frequency points of the excitation vibration source and record the vibration response of the bearing component, so that the frequency point is close to the natural frequency of the bearing component to achieve the maximum vibration response.

[0010] As an improvement, the support member includes a support leg and a support plate, and the support plate is provided with a first adjustment slot and a second adjustment slot; the support leg and the support plate are connected via a fastener cooperating with the first adjustment slot.

[0011] As an improvement, the excitation vibration source includes a speed regulating motor and a frequency converter for changing the speed of the speed regulating motor.

[0012] As an improvement, a vibration meter for detecting displacement, velocity, acceleration and frequency range is also included.

[0013] As an improvement, a counterweight block for changing the center of gravity of the bearing component is also included.

[0014] As an improvement, it also includes a supporting portion disposed at the bottom of the supporting member for providing static friction.

[0015] As an improvement, the support portion is a rubber pad for absorbing shock and vibration.

[0016] Another object of the present invention is to address the deficiencies in the prior art and to provide a method for verifying the results of resonance simulation. The vibration characteristic value of the model at a certain frequency point is obtained through simulation, and through the action of an actual speed-regulating motor, different frequencies are changed and dynamic characteristic parameters are recorded, which are compared with the dynamic parameters of the simulation to verify the accuracy of the simulation results, improve the accuracy of the simulation results, and provide experimental verification support for the design and optimization of large mechanical systems.

[0017] A method for verifying resonance simulation results comprises the following steps: Step 1: Simulation: First, use simulation software to simulate the dynamic response of the vibration test bench at different frequencies, and obtain the dynamic characteristics of the test bench such as natural frequency, vibration mode, amplitude, etc. through simulation calculation; Step 2: Extract simulation results: After the simulation calculation is completed, extract the simulation results corresponding to the most significant vibration mode of the test bench as comparison data; Step 3: Verify the simulation results: adjust the frequency of the speed regulating motor to be the same as the natural frequency obtained in step 1, detect and record the dynamic characteristic parameters of the test bench at this frequency point using a vibration meter, and compare them with the simulation results extracted in step 2. As an improvement, in step three, a frequency converter is used to adjust the speed of the motor, thereby changing the vibration frequency of the speed-regulating motor until the frequency of the motor reaches the natural frequency obtained in step one and fluctuates within a certain range. The vibration response of the test bench at different frequency points is detected and recorded by a vibration meter. As an improvement, the method further includes step 4, result judgment: if in step 3, the frequency of the motor is the same as the natural frequency of the test bench simulated in step 1, the amplitude of the test bench is the largest, and it is determined that the simulation result of step 1 is accurate.

[0018] The beneficial effects of the present invention are: (1) The present invention can intuitively display the lateral and longitudinal vibration phenomena of the mechanical system by changing the vibration frequency of the excitation vibration source, and can also display the vibration phenomenon in the vertical direction, thereby providing an excellent test device for verifying the vibration frequency obtained by simulation.

[0019] (2) The present invention adjusts the output of the frequency converter to change the speed of the speed regulating motor and achieves outputs of different vibration frequencies, thereby simulating the vibration phenomenon of the test bench at different frequencies and improving the accuracy and repeatability of the test results. The test device has a wide range of applicability and can completely cover the vibration frequencies of the simulation test results.

[0020] (3) The present invention uses the test bench as the basic equipment for studying the resonance phenomenon. By adjusting the size of the beam or adding other structural components, the vibration control and vibration reduction optimization strategies of the mechanical system can be further explored, providing an expandable test platform for in-depth exploration of the vibration reduction methods of the mechanical system.

[0021] (4) The motor-excited mechanical system resonance test bench of the present invention is widely used in the engineering field. It can help researchers to deeply understand the resonance phenomenon and the characteristics of dynamic systems, and build a bridge between theoretical research and engineering practice.

[0022] (5) The present invention has achieved technological innovation in the field of engineering teaching, helping researchers to better understand the resonance phenomenon. At the same time, in the industrial field, the test bench provides a valuable reference for the resonance research of large mechanical systems and has broad application prospects.

[0023] In summary, the present invention has the advantages of simple structure, stability and reliability, easy installation, portability, and convenient maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 This is the first-order mode of the test bench simulation experiment of the present invention, and the test bench is oscillating horizontally; Figure 3 This is a simulation diagram of the 2nd order mode of the test bench simulation experiment of the present invention, where the motor vibrates up and down in the Y direction on the test bench; Figure 4 This is the third-order mode of the test bench simulation experiment of the present invention, and the test bench is torsion-simulated in the longitudinal direction; Figure 5 This is the 4th order mode of the test bench simulation experiment of the present invention, and the simulation diagram of the motor vibrating violently in the Y direction on the test bench; Figure 6 This is a simulation diagram of the fifth-order mode of the test bench simulation experiment of the present invention, in which the beam near the motor undergoes severe torsion. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0027] Embodiment 1 like Figure 1-Figure 6 As shown, this embodiment provides a motor-excited mechanical system resonance demonstration test bench, comprising: Support member 1; The support member 2 is mounted on the support member 1 and is provided with a third adjustment slot 21; specifically, the support member 2 is connected to the second adjustment slot 122 via a fastener; the support member 2 is provided with a group, and is respectively connected to the second adjustment slot 122 via a fastener, and structural resonance simulations of different widths are achieved by changing the distance between a group of support members 2; An excitation vibration source 3, the excitation vibration source 3 generating different vibration frequencies is installed on the bearing member 2, and the excitation vibration source 3 is installed on the third adjustment slot 21 through a fastener; The different vibration frequency points of the excitation vibration source 3 are changed and the vibration response of the bearing member 2 is recorded, so that the frequency point is close to the natural frequency of the bearing member 2 to achieve the maximum vibration response.

[0028] It should be noted that the excitation vibration source 3 is installed on the third adjustment groove 21 by fasteners, which is convenient for adjusting the position of the excitation vibration source 3 relative to the supporting member 2 to achieve resonance demonstration at different vibration frequency points, and can also be used for expanded research on the resonance phenomenon of simple motor excitation mechanical systems.

[0029] That is, according to the actual design requirements of the simple motor-excited mechanical system, the motor's installation position (center, offset), supporting structure span (long span, short span), and component weighting (overall weight distribution adjustment) can be reasonably adjusted to achieve the purpose of changing the structural resonant frequency of the mechanical system. This is of great benefit to the study of the resonance occurrence law and vibration reduction and avoidance strategies of the mechanical system.

[0030] As an improvement, the support member 1 includes a support leg 11 and a support plate 12, and the support plate 12 is provided with a first adjustment groove 121 and a second adjustment groove 122; the support leg 11 and the support plate 12 are connected with fasteners through the first adjustment groove 121 to adjust the distance between the support legs 11, thereby realizing the simulation of structures with different center distances.

[0031] Preferably, the excitation vibration source 3 includes a speed regulating motor 31 and a frequency converter 32 for changing the speed of the speed regulating motor 31; the frequency converter 32 is electrically connected to the speed regulating motor 31; the speed regulating motor 31 is installed on the third adjustment slot 21 via fasteners.

[0032] As an improvement, a vibration meter 4 for detecting displacement, velocity, acceleration and frequency range is also included; the vibration meter 4 can be installed according to the adaptability of the position of the point to be measured. Preferably, the vibration meter 4 is installed on the speed regulating motor.

[0033] It should be noted that during the test, the speed regulating motor 31 is powered on and used as an excitation source. The knob of the frequency converter 32 is adjusted to change the speed of the motor, which is convenient for adjustment. During the operation of the motor, the high-precision vibration meter 4 can be stably adsorbed at a certain position of the motor. The vibration meter 4 can be directly connected to a computer to monitor the displacement, velocity, and acceleration effective peak value diagrams of the measured points of the mechanical system in real time. The vibration meter 4 can be connected to a computer via wireless transmission or USB transmission connection. The transmission method can be selected according to actual needs.

[0034] As an improvement, it also includes a counterweight block 5 for changing the center of gravity of the carrier 2; the counterweight block 5 is installed on the first adjustment slot 121, the second adjustment slot 122 or the third adjustment slot 21 through fasteners; by arranging the counterweight block 5 at different positions, the requirements of different test conditions are met and the diversity of the demonstration platform experimental process is improved.

[0035] Specifically, the counterweight block 5 is a stainless steel block with a round cake structure, and the weight can be selected according to different test requirements, such as 0.1Kg, 0.5Kg, 1Kg, etc.

[0036] Embodiment 2 like Figure 1As shown, the components identical or corresponding to those in the first embodiment are marked with the corresponding reference numerals in the first embodiment. For the sake of simplicity, only the differences from the first embodiment are described below. The second embodiment differs from the first embodiment in that: In this embodiment, it also includes a support portion 6 arranged at the bottom of the support member 1 for providing static friction; a large friction force is formed between the support portion 6 and the bottom of the support member 1 to ensure that the bottom of the support member 1 always remains relatively stationary with respect to the support portion 6 during the resonance process; that is, the support member 1 can tilt and swing, but the part in contact with the support portion 6 remains stationary relative to the support portion 6.

[0037] Preferably, the support portion 6 is a rubber pad. By providing the rubber pad, a greater friction force can be achieved between the support member 1 and the rubber pad, and the resonance demonstration test bench can be isolated from vibration to prevent external factors from affecting the test accuracy of the test bench.

[0038] It should be noted that during use, the rubber pad is placed on a horizontal working surface 7 to provide support for the support member 1, help stabilize the system structure, and prevent tilting or movement. The working surface 7 can be the ground or a workbench; at the same time, the good elasticity and cushioning properties of rubber are utilized to effectively absorb shocks and vibrations and reduce the noise generated during the operation of the mechanical system.

[0039] Embodiment 3 This embodiment provides a method for verifying resonance simulation results, comprising the following steps: Step 1: Simulation: First, use simulation software, preferably ANSYS, to simulate the dynamic response of the vibration test bench at different frequencies, and obtain the key dynamic characteristics of the test bench such as the natural frequency, vibration mode, and amplitude through simulation calculation; It should be noted that through the dynamic response at different frequencies, the frequency under the condition of the maximum amplitude of the test bench model is the natural frequency of the test bench, and the vibration mode, amplitude and other parameters at this frequency are recorded at the same time; Figure 2-Figure 6 As shown, it simulates the dynamic vibration response of the test bench at different frequencies; Step 2: Extract simulation results: After the simulation calculation is completed, extract the simulation results corresponding to the most significant vibration mode of the test bench as comparison data; Step 3, simulation result verification: adjust the frequency of the speed regulating motor 31 to be the same as the natural frequency obtained in step 1, detect and record the dynamic characteristic parameters of the test bench at this frequency point through the vibration meter 4, and compare them with the simulation results extracted in step 2; it should be noted that if the dynamic characteristic parameters obtained in step 3 are the same as the simulation results extracted in step 2, the simulation data of the test bench is accurate, otherwise, it is inaccurate.

[0040] As an improvement, in step three, the frequency converter 32 is used to adjust the speed of the motor, thereby changing the vibration frequency of the speed regulating motor 31, until the frequency of the motor reaches the natural frequency obtained in step one and fluctuates up and down within a certain interval, and the vibration response of the test bench at different frequency points is detected and recorded by the vibration meter 4; if it is necessary to explain, the vibration response includes but is not limited to parameters such as amplitude, frequency, speed, acceleration, etc.; Preferably, the method further includes step 4, result judgment: if in step 3, the frequency of the motor is the same as the natural frequency of the test bench simulated in step 1, the amplitude of the test bench is the largest, and it is determined that the simulation result of step 1 is accurate.

[0041] It should be noted that when the maximum amplitude of the test bench (i.e., resonance) occurs in step three and the motor frequency is less than the natural frequency simulated in step one, it means that the natural frequency value obtained in step one is too large; When the maximum amplitude of the test bench (i.e. the resonance) occurs in step 3 and the motor frequency is greater than the natural frequency simulated in step 1, it means that the natural frequency value obtained in step 1 is too small; Therefore, the accuracy of the simulation parameters can be inferred based on the actual verification results, thereby continuously improving the accuracy of the simulation.

[0042] In addition, during the experiment, it is necessary to pay attention to the vibration of the test bench when it approaches or reaches the natural frequency. When the vibration frequency of the motor is consistent with the natural frequency of the test bench, a significant resonance phenomenon will occur, and the amplitude will increase sharply. By comparing the vibration phenomenon observed in the experiment with the simulation results, the accuracy of the simulation model and its ability to predict the actual structural dynamic characteristics can be clearly verified.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A motor-excited mechanical system resonance demonstration test bench, characterized in that: Also includes: Supports; A bearing member, the supporting member is mounted on the supporting member and is provided with a third adjusting slot; An excitation vibration source, the excitation vibration source generating different vibration frequencies is mounted on the bearing member, and the excitation vibration source is mounted on the third adjustment slot via a fastener; Change the different vibration frequency points of the excitation vibration source and record the vibration response of the bearing component, so that the frequency point is close to the natural frequency of the bearing component to achieve the maximum vibration response.

2. A motor excitation mechanical system resonance demonstration test bench according to claim 1, characterized in that: The support member comprises a support leg and a support plate, wherein the support plate is provided with a first adjustment slot and a second adjustment slot; the support leg and the support plate are connected via a fastener in the first adjustment slot.

3. The motor excitation mechanical system resonance demonstration test bench according to claim 1 is characterized in that: The excitation vibration source includes a speed regulating motor and a frequency converter for changing the speed of the speed regulating motor.

4. The motor excitation mechanical system resonance demonstration test bench according to claim 1, characterized in that: Also included are vibration meters for measuring displacement, velocity, acceleration and frequency ranges.

5. The motor excitation mechanical system resonance demonstration test bench according to claim 1, characterized in that: Also included is a counterweight block for changing the center of gravity of the bearing member.

6. The motor-excited mechanical system resonance demonstration test bench according to claim 1, characterized in that: It also includes a supporting portion disposed at the bottom of the supporting member for providing static friction.

7. A motor excitation mechanical system resonance demonstration test bench according to claim 6, characterized in that: The supporting part is a rubber pad for absorbing shock and vibration.

8. A method for verifying resonance simulation results, comprising the following steps: Step 1: Simulation: First, use simulation software to simulate the dynamic response of the vibration test bench at different frequencies, and obtain the natural frequency, vibration mode, and amplitude dynamic characteristics of the test bench through simulation calculation; Step 2: Extract simulation results: After the simulation calculation is completed, extract the simulation results corresponding to the most significant vibration mode of the test bench as comparison data; Step 3: Verify the simulation results: adjust the frequency of the speed regulating motor to be the same as the natural frequency obtained in step 1, detect and record the dynamic characteristic parameters of the test bench at this frequency point using a vibration meter, and compare them with the simulation results extracted in step 2.

9. A method for verifying resonance simulation results according to claim 8, characterized in that: In step three, a frequency converter is used to adjust the speed of the motor, thereby changing the vibration frequency of the speed-regulating motor until the frequency of the motor reaches the natural frequency obtained in step one and fluctuates within a certain range. The vibration response of the test bench at different frequency points is detected and recorded by a vibration meter.

10. A method for verifying resonance simulation results according to claim 8, characterized in that: The method also includes step 4, result judgment: if in step 3, the frequency of the motor is the same as the natural frequency of the test bench simulated in step 1, the amplitude of the test bench is the largest, and it is determined that the simulation result of step 1 is accurate.

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