CN111923936A - Quasi-zero stiffness vibration isolator for railway vehicle traction motor - Google Patents

Abstract

The invention relates to a quasi-zero stiffness vibration isolator for a railway vehicle traction motor, which comprises a plurality of quasi-zero stiffness vibration isolators arranged above and at two sides of a frame cross beam of a vehicle body, wherein each quasi-zero stiffness vibration isolator is symmetrically arranged by taking the frame cross beam as the center, each quasi-zero stiffness vibration isolator is connected with a connecting support, the connecting support is rigidly connected with a motor support of the motor, each quasi-zero stiffness vibration isolator comprises a quasi-zero stiffness vibration isolator upper end mounting seat, a quasi-zero stiffness vibration isolator lower end mounting seat, a disc spring and a rubber spring, the disc spring is connected with the rubber spring in parallel, two ends of the disc spring and two ends of the rubber spring are respectively and fixedly connected with the quasi-zero stiffness vibration isolator upper end mounting seat and the quasi-zero stiffness vibration isolator lower end mounting seat, and the

Compared with the prior art, the invention is beneficial toReduce the vibration of the framework, improve the operation stability and the safety of the framework and the like.

Description

A quasi-zero stiffness vibration isolator for traction motors of railway vehicles

technical field

The invention relates to the technical field of railway vehicles, in particular to a quasi-zero stiffness vibration isolator for traction motors of railway vehicles.

Background technique

With the continuous development of railway vehicle technology, more and more people choose to travel by subway or high-speed rail. At present, the subway or high-speed railway mainly adopts the power dispersion technology, and the drive motor needs to be installed on the power bogie. The drive motor is the core component of the drive system and one of the vibration sources of the bogie. How to install it on the frame reasonably and take appropriate vibration isolation measures Reducing frame vibration is a key issue in motor suspension. If the motor vibration isolation measures are not taken properly, it may cause the frame to vibrate too much, threatening the operation safety.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a quasi-zero stiffness vibration isolator for the traction motor of a railway vehicle, which is aimed at the vibration of the traction motor, reduces the vibration of the frame, and improves the running stability and safety of the frame in order to overcome the defects of the above-mentioned prior art. .

The object of the present invention can be realized through the following technical solutions:

A quasi-zero stiffness vibration isolator for a traction motor of a railway vehicle, comprising a plurality of quasi-zero stiffness vibration isolators arranged above and on both sides of a frame beam of a vehicle body, each quasi-zero stiffness vibration isolator is centered on the frame beam In a symmetrical arrangement, each quasi-zero stiffness vibration isolator is connected with a connecting bracket, and the connecting bracket is rigidly connected with the motor bracket of the motor.

The quasi-zero-stiffness vibration isolator includes an upper-end mounting seat of the quasi-zero-stiffness vibration isolator, a lower-end mounting seat of the quasi-zero-stiffness vibration isolator, a disc spring and a rubber spring, and the upper-end mounting seat of the quasi-zero stiffness vibration isolator and a connecting bracket connection, the lower end mounting seat of the quasi-zero stiffness vibration isolator is connected to the frame beam of the vehicle body, the disc spring is connected in parallel with the rubber spring, the two ends of the disc spring and the two ends of the rubber spring are respectively It is connected with the upper end mounting seat of the quasi-zero stiffness vibration isolator and the lower end mounting seat of the quasi-zero stiffness vibration isolator. The disc spring and the rubber spring are in a parallel relationship, and the stiffness of the vibration isolator is equal to the sum of the two stiffnesses.

且为支撑面的预压缩碟形弹簧，工作过程中提供负刚度。所述橡胶弹簧为圆环形结构，工作过程中提供正刚度。Further, the ratio of the height to the thickness of the disc spring is greater than

And it is the pre-compressed disc spring of the support surface, which provides negative stiffness during the working process. The rubber spring is a ring-shaped structure and provides positive stiffness during operation.

Further, the lower end mounting seat of the quasi-zero stiffness vibration isolator adopts bolts and is connected with the frame beam through the mounting ring. The mounting ring and the lower end mounting seat of the quasi-zero stiffness vibration isolator are respectively connected with the connecting bracket.

Further, a lubricating layer is respectively provided between the mounting ring and the connecting bracket, and between the lower end mounting seat of the quasi-zero stiffness vibration isolator and the connecting bracket to release the lateral and longitudinal stiffness of the vibration isolator.

Further, the upper end mounting seat of the quasi-zero stiffness vibration isolator and the connecting bracket are connected by bolts.

Further, one or more quasi-zero stiffness vibration isolators are respectively arranged above and on both sides of the frame beam.

Further, the mounting ring is an annular rigid structure.

The working principle of the present invention for the quasi-zero stiffness vibration isolator of the traction motor of the railway vehicle is as follows:

A quasi-zero stiffness vibration isolator was designed by using the negative stiffness characteristic of the disc spring and in parallel with the rubber spring, which is used for the motor suspension of the railway vehicle. The design steps are: design the rubber spring so that the static deflection of the vertical stiffness under the rated load state is equivalent to the static deflection of the common motor rubber shock absorber, and the function is the same as that of the common rubber shock absorber; then, the height of the disc spring is designed. , thickness, inner diameter and outer diameter parameters, so that the negative stiffness of the equilibrium position under the rated load state and the vertical stiffness of the rubber spring are superimposed to obtain a quasi-zero stiffness; layer and mounting ring, so that the disc spring and the rubber spring are connected in parallel, and the lateral stiffness of the disc spring is released.

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

能够使橡胶弹簧在垂向刚度与碟形弹簧负刚度叠加后得到准零刚度，当系统在此准零刚度平衡位置附近做小幅度振动时，由于准零刚度系统的隔振起始频率低，隔振频带宽，电机的振动主频通常在20Hz以上，而本发明提出的准零刚度隔振系统起始隔振频率可以低至1Hz，对于大于1Hz的振动频率具有很好的隔离效果，因此可以有效隔离电机传递至构架的振动，使电机以准零刚度悬挂的形式连接于构架，有利于降低构架振动，提高构架运行稳定性和安全性，防止构架由于振动过大导致疲劳损伤；(1) The disc spring negative stiffness mechanism that only provides negative stiffness is used in parallel with the rubber spring, and the height-to-thickness ratio of the disc spring is greater than

The quasi-zero stiffness of the rubber spring can be obtained after the vertical stiffness and the negative stiffness of the disc spring are superimposed. When the system vibrates with a small amplitude near the equilibrium position of the quasi-zero stiffness, due to the low initial frequency of vibration isolation of the quasi-zero stiffness system, The vibration isolation frequency bandwidth is wide, and the main vibration frequency of the motor is usually above 20Hz, and the initial vibration isolation frequency of the quasi-zero stiffness vibration isolation system proposed by the present invention can be as low as 1Hz, and has a good isolation effect for vibration frequencies greater than 1Hz. Therefore, It can effectively isolate the vibration transmitted by the motor to the frame, so that the motor is connected to the frame in the form of quasi-zero stiffness suspension, which is beneficial to reduce the vibration of the frame, improve the stability and safety of the frame, and prevent the frame from fatigue damage due to excessive vibration;

(2) In view of the vibration of the traction motor, the present invention is provided with quasi-zero stiffness vibration isolators above and on both sides of the frame beam of the vehicle body, and structurally combined with the frame beam, so that the quasi-zero stiffness vibration isolator is installed in the lateral and Can be arranged vertically;

(3) When the mounting ring, the lower end mounting seat of the vibration isolator and the motor bracket are connected and installed, there is a lubricating layer in the middle, which can release the lateral and longitudinal stiffness of the quasi-zero stiffness vibration isolator;

(4) The present invention has simple and compact structure, convenient production and installation, and good vibration isolation performance.

Description of drawings

1 is a schematic structural diagram of a quasi-zero stiffness vibration isolator for a traction motor of a railway vehicle in an embodiment;

Fig. 2 is the structural schematic diagram of the quasi-zero stiffness vibration isolator in the embodiment;

3 is a schematic structural diagram of a disc spring in an embodiment; wherein, FIG. 3(a) is a schematic cross-sectional front view structure of a disc spring, and FIG. 3(b) is a top-view structural schematic diagram of the disc spring;

4 is a schematic structural diagram of a rubber spring in an embodiment, wherein FIG. 4( a ) is a schematic front view structure of the rubber spring, and FIG. 4( b ) is a side view structural schematic diagram of the rubber spring;

Fig. 5 is the force characteristic curve diagram of the disc spring and the rubber spring in the embodiment;

Fig. 6 is the stiffness-displacement relation diagram of the quasi-zero stiffness vibration isolator in the embodiment;

The numbers in the figure show:

1. Disc spring, 2. Rubber spring, 3. Upper mounting seat of quasi-zero stiffness vibration isolator, 4. Lower mounting seat of quasi-zero stiffness vibration isolator, 5. Lubricating layer, 6. Mounting ring, 7. Frame beam, 8. Connecting bracket, 9. Motor bracket, 10. Motor.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Example

As shown in FIG. 1, the present invention relates to a quasi-zero stiffness vibration isolator for traction motors of railway vehicles, comprising a disc spring 1, a rubber spring 2, a mounting seat 3 on the upper end of the quasi-zero stiffness vibration isolator, and a quasi-zero stiffness vibration isolator The lower end mounting seat 4 , the lubricating layer 5 , the mounting ring 6 , the frame beam 7 , the connecting bracket 8 , the motor bracket 9 and the motor 10 .

The disc spring 1, the rubber spring 2, the upper end mounting seat 3 of the quasi-zero stiffness vibration isolator, and the lower end mounting seat 4 of the quasi-zero stiffness vibration isolator constitute a quasi-zero stiffness vibration isolator. Specifically, the two ends of the disc spring 1 are respectively fixedly connected to the upper end mounting seat 3 of the quasi-zero stiffness vibration isolator and the lower end mounting seat 4 of the quasi-zero stiffness vibration isolator, the rubber spring 2 is connected to the disc spring 1 in parallel, and the rubber spring 2 The two ends of the quasi-zero stiffness vibration isolator are respectively fixedly connected with the upper end mounting seat 3 of the quasi-zero stiffness vibration isolator and the lower end mounting seat 4 of the quasi-zero stiffness vibration isolator. Preferably, the upper mounting seat 3 of the quasi-zero stiffness vibration isolator is fixedly connected to one end of the outer ring of the disc spring 1 , and the lower mounting seat 4 of the quasi-zero stiffness vibration isolator is fixedly connected to one end of the inner ring of the disc spring 1 .

且为预压缩碟形弹簧，工作过程中提供负刚度。橡胶弹簧2的结构图如图4所示，为圆环形，工作过程中提供正刚度。The disc spring 1 and the rubber spring 2 are in a parallel relationship, and the stiffness of the quasi-zero stiffness vibration isolator is equal to the sum of the two stiffnesses; the structure diagram of the disc spring 1 is shown in Figure 3, and its height-to-thickness ratio is greater than

And it is a pre-compressed disc spring, which provides negative stiffness during operation. The structure diagram of the rubber spring 2 is shown in Fig. 4, which is a circular ring, and provides positive stiffness during the working process.

The upper mounting seat 3 of the quasi-zero stiffness vibration isolator is connected to the connecting bracket 8 by bolts. The connection bracket 8 is rigidly connected with the motor bracket 9, and can be connected by bolts or welding. The lower end mounting seat 4 of the quasi-zero stiffness vibration isolator is connected to the frame beam 7 of the vehicle body through the mounting ring 6 . Quasi-zero stiffness vibration isolators are arranged above and on both sides of the frame beam 7 , and each quasi-zero stiffness vibration isolator is symmetrically arranged with the frame beam 7 as the center. One or more quasi-zero stiffness vibration isolators can be arranged above and on both sides of the frame beam 7 .

Specifically, the lower end mounting seat 4 of the quasi-zero stiffness vibration isolator adopts bolts, and is connected to the frame beam 7 through the mounting ring 6 . When the mounting ring 6, the lower end mounting seat 4 of the vibration isolator and the connecting bracket 8 are connected and installed, a lubricating layer 5 is provided in the middle to release the lateral and longitudinal stiffness of the vibration isolator. Preferably, the mounting ring 6 is an annular rigid structure.

The specific installation process of the quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle in this embodiment is as follows:

A quasi-zero stiffness vibration isolator is designed by using the negative stiffness characteristic of the disc spring 1 in parallel with the rubber spring 2, which is used for the motor suspension of the railway vehicle. The design steps are: design the rubber spring 2 so that the static deflection of its vertical stiffness under the rated load-bearing state is equivalent to the static deflection of the common motor rubber shock absorber, and its function is the same as that of the common rubber shock absorber; then, design the disc spring The parameters of height, thickness, inner diameter, and outer diameter of 1 make the negative stiffness of the equilibrium position and the vertical stiffness of the rubber spring superimposed under the rated load state to obtain the quasi-zero stiffness; , The lower end mounting seat 4 of the quasi-zero stiffness vibration isolator, the lubricating layer 5, and the mounting ring 6, so that the disc spring 1 and the rubber spring 2 are connected in parallel, and the lateral stiffness of the disc spring 1 is released.

In this embodiment, a disc spring without a supporting surface is used, and the schematic cross-sectional view is shown in Fig. 3(a). In the figure, t _c is the thickness, h ₀ is the initial height, D is the outer diameter, and d is the inner diameter. The parameter design formula of the disc spring in the design step is:

In the formula, E is the elastic modulus, μ is the Poisson’s ratio, x is the vertical displacement of the disc spring from the initial position, and the parameter K ₁ is related to the ratio C (C=D/d) of the outer and inner diameters:

The disc spring has the principle of negative stiffness characteristics and its calculation is:

时，其受力特性会出现一段负刚度区域(特性曲线斜率为负值的区域)。Disc springs will show different force characteristics according to their height-to-thickness ratios. When the height-to-thickness ratio is greater than

When , its force characteristic will appear in a negative stiffness region (the region where the slope of the characteristic curve is negative).

In order to study the negative stiffness characteristics of disc springs, formula (1) is simplified, so that:

Substitute into formula (1) to get

Taking the derivative of the above formula with respect to x, the stiffness expression of the disc spring can be obtained as:

此时负刚度的区间为：It can be seen that the stiffness k _d of the disc spring is a quadratic function of the deformation x, and its symmetry axis is x=αt _c , and k _d (0)=λ(α ² +1)/t _c >0, it is necessary to For the disc spring to have a negative stiffness interval, it must satisfy Δ=(-3α) ² -6(α ² +1)>0, that is,

At this time, the interval of negative stiffness is:

Sub-figure (a) in Fig. 5 is the force-displacement curve diagram of the disc spring. There is a region with negative stiffness characteristics (negative curvature) in the figure, which is similar to the disc spring stiffness of sub-figure (a) in Fig. 6- This corresponds to the negative stiffness (stiffness less than 0) region of the displacement curve. The negative stiffness is unstable during the vibration process, so the positive stiffness of the rubber spring is added as stiffness compensation, and the force-displacement curve of the rubber spring is shown in sub-figure (b) in Figure 5. In a parallel relationship, the two forces are added together, and the combined force-displacement curve is shown in subgraph (c) in Figure 5, and the corresponding stiffness-displacement curve is shown in subgraph (b) in Figure 6. The stiffness has no negative stiffness area, and the stiffness is equal to 0 at the equilibrium position (1.5mm in the figure), that is, the quasi-zero stiffness characteristic. For the quasi-zero stiffness shock absorber installed on the bogie drive motor, when the system vibrates at a small amplitude near the quasi-zero stiffness equilibrium position, due to the low initial frequency of vibration isolation of the quasi-zero stiffness system and the bandwidth of the vibration isolation frequency, it can be Effectively isolate the vibration transmitted from the motor to the frame to improve the stability of the frame and prevent the frame from fatigue damage due to excessive motor excitation vibration.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Any person familiar with the technical field can easily think of various equivalents within the technical scope disclosed by the present invention. Modifications or substitutions should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (10)

1. The quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle is characterized by comprising a plurality of quasi-zero stiffness vibration isolators arranged above and on two sides of a framework cross beam of a vehicle body, wherein each quasi-zero stiffness vibration isolator is symmetrically arranged by taking the framework cross beam as a center, and is connected with a connecting support, and the connecting support is rigidly connected with a motor support of the motor.

2. The quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle as claimed in claim 1, wherein the quasi-zero stiffness vibration isolator comprises a quasi-zero stiffness vibration isolator upper end mounting seat, a quasi-zero stiffness vibration isolator lower end mounting seat, a disc spring and a rubber spring, the quasi-zero stiffness vibration isolator upper end mounting seat is connected with a connecting support, the quasi-zero stiffness vibration isolator lower end mounting seat is connected with a framework cross beam of a vehicle body, the disc spring is connected with the rubber spring in parallel, and two ends of the disc spring and two ends of the rubber spring are respectively connected with the quasi-zero stiffness vibration isolator upper end mounting seat and the quasi-zero stiffness vibration isolator lower end mounting seat.

3. The quasi-zero stiffness vibration isolator for railway vehicle traction motors of claim 1, wherein the disc springs are pre-compressed disc springs without bearing surfaces.

4. The method of claim 1The quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle is characterized in that the height-to-thickness ratio of the disc spring is larger than that of the disc spring

5. The quasi-zero stiffness vibration isolator for railway vehicle traction motors of claim 1, wherein the rubber spring is circular ring shaped.

6. The quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle as claimed in claim 2, wherein the lower end mounting seat of the quasi-zero stiffness vibration isolator is connected with the frame beam through a mounting ring by a bolt, and the mounting ring and the lower end mounting seat of the quasi-zero stiffness vibration isolator are respectively connected with the connecting bracket.

7. The quasi-zero stiffness vibration isolator for the traction motor of the railway vehicle as claimed in claim 6, wherein a lubricating layer is respectively arranged between the mounting ring and the connecting bracket and between the mounting seat at the lower end of the quasi-zero stiffness vibration isolator and the connecting bracket.

8. The quasi-zero stiffness vibration isolator for railway vehicle traction motors of claim 2, wherein the mounting seat at the upper end of the quasi-zero stiffness vibration isolator is connected with the connecting bracket through a bolt.

9. The quasi-zero stiffness vibration isolator for railway vehicle traction motors of claim 1, wherein one or more quasi-zero stiffness vibration isolators are respectively disposed above and on both sides of the frame cross beam.

10. The quasi-zero stiffness vibration isolator for railway vehicle traction motors of claim 6, wherein the mounting ring is a circular ring shaped rigid structure.

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