阅读说明：本技术 一种准零刚度轴箱弹簧减振方法及弹簧 (Quasi-zero stiffness axle box spring vibration reduction method and spring ) 是由 陈清化 王玉辉 褚衍廷 陈铖 杨晓林 钱娜 王文静 俞雷 邢湘利 邹震 颜毅斌 于 2019-09-26 设计创作，主要内容包括：本发明提供一种准零刚度轴箱弹簧减振方法及弹簧,所述轴箱弹簧包括橡胶锥形弹簧,所述橡胶锥形弹簧芯轴呈空心状；所述橡胶锥形弹簧的芯轴内内置并联安装有负刚度装置。本发明所提供的轴箱弹簧将橡胶锥形弹簧与负刚度装置内置并联安装,既能在平衡位置实现准零刚度,得到较低的固有频率,实现低频隔振,有效抑制轮轴低频振动成分对构架及车体的影响,又可以提供较大垂向刚度,满足列车大负载时减小装置变形挠度的要求,确保了列车运行的安全性与平稳性。(The invention provides a damping method for a quasi-zero stiffness axle box spring and a spring, wherein the axle box spring comprises a rubber conical spring, and a core shaft of the rubber conical spring is hollow; and a negative stiffness device is arranged in a mandrel of the rubber conical spring in parallel. The axle box spring provided by the invention has the advantages that the rubber conical spring and the negative stiffness device are arranged in parallel, so that the quasi-zero stiffness can be realized at the balance position, the lower inherent frequency is obtained, the low-frequency vibration isolation is realized, the influence of the low-frequency vibration component of the axle on the framework and the train body is effectively inhibited, the larger vertical stiffness can be provided, the requirement of reducing the deformation deflection of the device when the train is under a large load is met, and the safety and the stability of the train operation are ensured.)

1. A damping method for a quasi-zero stiffness axle box spring is characterized in that a rubber conical spring is used as a main spring, a hole is formed in a mandrel in the rubber conical spring, and a negative stiffness device is arranged in the hole in parallel; setting the bearing surface of the rubber conical spring and the bearing surface of the negative stiffness device to have a certain height difference; the rubber conical spring bears the load firstly, and when the rubber conical spring is compressed to a certain proportion, the negative stiffness device begins to bear the load and provides vertical stiffness together with the rubber conical spring; when the balance position is reached, the negative stiffness device provides negative stiffness, and a quasi-zero stiffness interval can be formed after the negative stiffness is offset with the positive stiffness of the rubber conical spring.

2. A quasi-zero stiffness pedestal spring based on the damping method of claim 1, wherein the rubber conical spring mandrel is hollow; a negative stiffness device connected with the hollow core shaft of the rubber conical spring in parallel is arranged in the hollow core shaft of the rubber conical spring.

3. The quasi-zero stiffness axlebox spring of claim 2 wherein the bottom of the spindle is provided with a removable base; the base is fixed by a screw, and a concave platform is arranged in the circumferential direction of the base.

4. The quasi-zero stiffness axlebox spring according to claim 2 wherein the negative stiffness means comprises a transmission means, an electromagnetic means, an outer sleeve; the outer sleeve is fixed with the base together in a screw fastening mode.

5. The quasi-zero stiffness axlebox spring according to claim 4 wherein a gap B exists between the top end of the transfer device and the top end of the mandrel when the negative stiffness device is in the pre-installed position; a gap A exists between the lower end face of the transmission device and the top end of the outer sleeve.

6. The quasi-zero stiffness axlebox spring according to claim 5 wherein the gap B is no greater than gap A.

7. The quasi-zero stiffness axlebox spring according to claim 4 wherein a gap C exists between the top end of the transfer device and the top end of the outer casing of the rubber conical spring when the negative stiffness device is in the pre-installed position.

8. The quasi-zero stiffness axlebox spring of claim 7 wherein the clearance C is not less than an amount of drop of the rubber conical spring housing when the vehicle is unloaded.

9. The quasi-zero stiffness axlebox spring according to claims 1-8 wherein the loaded motion travel of the quasi-zero stiffness axlebox spring is the sum of gap B and gap C.

10. The quasi-zero stiffness axlebox spring of claim 4 wherein a wear plate is mounted to the top of the transfer device.

Technical Field

The invention relates to the field of vibration reduction of rail vehicles, in particular to a vibration reduction method of a quasi-zero stiffness axle box spring and the spring.

Background

Because of the advantages of vibration reduction and noise reduction of rubber, at present, conical rubber springs are generally adopted to be used as axle box springs on many urban rail transit vehicles at home and abroad, but with the development of the current city, the requirements of people on vehicle riding comfort and noise interference prevention are higher and higher. The vibration between the wheel rails and the vibration generated by the wheel axle vibration are transmitted to the framework through the first series of axle box springs and then transmitted to the second series of springs and the vehicle body. The vibration and noise reduction efficiency of the conical spring is improved greatly compared with that of a single steel spring. According to the linear vibration theory, for a common spring vibration isolator, no matter the excitation effect of harmonic force or basic vibration, the vibration isolation effect can be generated only when the external excitation frequency is more than the system natural frequency of 2 times of root number.

Therefore, to effectively reduce the influence of the vibration of the wheel rail and the wheel axle on the frame and the vehicle body, the conventional method is to reduce the natural frequency of the relevant component structure, and for the tapered rubber journal box spring, the mass of the journal box spring can be increased or the vertical stiffness of the journal box spring can be reduced. However, the mass of the axle box spring is limited by the weight of the whole bogie, and the mass is obviously not increased when the weight reduction, energy conservation and environmental protection are advocated; the reduction of the rigidity enables the natural frequency of the journal box spring to be lower, but the movement displacement of the framework can be increased, namely, the vertical deflection is increased, and the safety of train operation is greatly influenced.

Disclosure of Invention

The invention aims to provide an axle box spring damping method and a spring, which have the advantages of high bearing capacity, small deformation, good low-frequency vibration isolation effect and large vibration isolation frequency range.

The specific technical scheme of the invention is as follows:

a quasi-zero stiffness journal box spring comprises a rubber conical spring, wherein a mandrel of the rubber conical spring is hollow; a negative stiffness device connected with the hollow core shaft of the rubber conical spring in parallel is arranged in the hollow core shaft of the rubber conical spring.

Furthermore, a detachable base is arranged at the bottom of the mandrel; the base is fixed by a screw, and a concave platform is arranged in the circumferential direction of the base.

Further, the negative stiffness device comprises a transmission device, an electromagnetic device and a jacket; the outer sleeve is fixed with the base together in a screw fastening mode.

Further, when the negative stiffness device is in the pre-installation position, a gap B exists between the top end of the transmission device and the top end of the mandrel; a gap A exists between the lower end face of the transmission device and the top end of the outer sleeve.

Further, the gap B is not greater than the gap a.

Further, when the negative stiffness device is in the pre-installation position, a gap C exists between the top end of the transmission device and the top end of the outer sleeve of the rubber conical spring.

Further, the clearance C is not less than the descending amount of the rubber conical spring outer sleeve when the vehicle is unloaded.

Further, the loaded motion stroke of the quasi-zero stiffness journal spring is the sum of the clearance B and the clearance C.

Further, a wear plate is mounted on the top of the transfer device.

The axle box spring provided by the technical scheme adopts a design method and a damping principle as follows:

a rubber conical spring is used as a main spring, a hole is formed in a core shaft in the rubber conical spring, and then a negative stiffness device is connected in parallel in the hole; a certain height difference is arranged between the bearing surface of the rubber conical spring and the bearing surface of the negative stiffness device; in the working process, when the rubber conical spring is compressed to a certain position, the negative stiffness device starts to bear the weight and provides larger vertical stiffness together with the rubber conical spring; when the balance position is reached, the negative stiffness device provides negative stiffness, and a quasi-zero stiffness interval can be formed after the negative stiffness device is offset with the positive stiffness of the rubber conical spring, so that the whole axle box spring obtains lower natural frequency, and low-frequency vibration isolation can be realized.

The invention has the following beneficial effects:

(1) according to the axle box spring provided by the invention, the rubber conical spring and the negative stiffness device are arranged in parallel, so that quasi-zero stiffness can be realized at a balance position, lower inherent frequency can be obtained, low-frequency vibration isolation is realized, and the influence of low-frequency vibration components of an axle on a framework and a vehicle body is effectively inhibited; and the device can provide larger vertical rigidity, meet the requirement of reducing the deformation deflection of the device when the train is under heavy load, and ensure the safety and the stability of train operation.

(2) The invention improves the core shaft structure of the rubber conical spring, so that the installation of the negative stiffness device is facilitated, and meanwhile, the installation space can be saved; meanwhile, some reliability designs are made, so that the positioning of parts is facilitated, and the service life of the device is prolonged.

Drawings

FIG. 1 is a schematic diagram of a quasi-zero stiffness axlebox spring of the present invention;

FIG. 2 is a comparison of load displacement curves for the present invention;

fig. 3 is a schematic structural diagram of a negative stiffness device.

Detailed Description

The invention is further described with reference to the following figures and examples. Wherein the showings are for the purpose of illustration only and are shown by way of illustration only and not in actual form, and are not to be construed as limiting the present patent; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

As shown in fig. 1, the present invention provides a quasi-zero stiffness journal box spring, the main body of which is a rubber conical spring, the rubber conical spring includes a vulcanized and glued outer sleeve 2, spacers 3, 5, rubber 4 and a mandrel 6, wherein the mandrel 6 is hollow, and a negative stiffness device is installed in parallel inside the hollow mandrel 6, and the negative stiffness device includes a transmission device 7a, an electromagnetic device 7b and an outer sleeve 7 c; the bottom of the mandrel 6 is connected with a base 9 through a screw 8, an outer sleeve 7c of the negative stiffness device is fixed on the base 9 through a screw 10, and a concave platform 9a in the circumferential direction of the base 9 mainly prevents the base from generating a large shearing action on the screw 8 and the screw 7 due to transverse force, so that the reliability of a product is improved; the electromagnetic device 7b is arranged inside the outer sleeve 7c, and the transmission device 7a can go up and down along the inner wall of the mandrel.

When the negative stiffness device is in the pre-installation position, a gap B exists between the top end of the transmission device 7a and the top end of the mandrel 6; a gap A exists between the lower end face of the transmission device 7a and the top end of the outer sleeve 7c, and the gap A is the sliding stroke of the transmission device 7a, so that B is required to be less than or equal to A, and the bottom of the transmission device 7a is prevented from being excessively extruded.

When the negative stiffness device is at the pre-installation position, a clearance C exists between the top end of the transmission device 7a and the top end of the outer sleeve 2 of the rubber conical spring, the clearance C is not smaller than the descending amount of the outer sleeve of the rubber conical spring when the vehicle is in no-load, and the top end of the transmission device 7a is provided with a wear-resisting plate; the sum of the clearance C and the clearance B is the loaded motion stroke of the whole axle box spring device.

As shown in fig. 2, the quasi-zero stiffness axlebox spring provided by the present invention specifically works as follows, when the vehicle is unloaded, the rubber conical spring is solely loaded, and when the descending amount of the rubber conical spring housing 2 is smaller than the clearance C, in the figure, the load displacement curve is a straight line, and the load displacement curve of the rubber spring plus negative stiffness device coincides with the straight line, that is, the stiffness of the whole device is not changed. When the descending amount of the rubber conical spring outer sleeve 2 is larger than the clearance C after the vehicle is loaded, the negative stiffness device is contacted with the vehicle body and is loaded together with the rubber conical spring to provide vertical stiffness, namely the whole axle box spring has larger stiffness under large load, the deformation deflection can be reduced, the stability of vehicle operation is kept, and the load displacement curve of the rubber spring plus negative stiffness device in the figure 2 is in nonlinear change; when the transmission device 7a is pressed down to a certain degree, that is, reaches the equilibrium position, the negative stiffness device plays a role of providing negative stiffness, so that the whole axle box spring device obtains low dynamic stiffness, the dynamic stiffness approaches zero and is greater than zero, as shown in a quasi-zero stiffness interval in fig. 2, the dynamic stiffness of the whole device at the position approaches zero infinitely, and thus the whole axle box spring device can obtain very low natural frequency, thereby realizing low-frequency vibration isolation.

In conclusion, the axle box spring and the vibration damping method thereof provided by the invention can provide enough rigidity under a large load, reduce the vertical deformation deflection of the device and maintain the stability of train operation; and a quasi-zero stiffness interval can be generated at a balance position, a lower natural frequency is obtained, the effect of low-frequency vibration isolation is achieved, the influence of wheel rail and wheel shaft vibration on a framework and a vehicle body is effectively inhibited, and the axle box spring device capable of realizing zero-stiffness vibration isolation can be designed.

As shown in fig. 3, the negative stiffness device used in the present embodiment includes a transmission device 7a, an electromagnetic device 7b and an outer casing 7c, the electromagnetic device 7b is disposed in the outer casing 7c and includes a pair of longitudinal moving magnets 7b1 and a pair of transverse moving magnets 7b3, the two pairs of magnets are fixed to an iron core 7b5 connected to the transmission device 7a and can move longitudinally with the transmission device 7a, and a pair of longitudinal static magnets 7b2 and a pair of transverse static magnets 7b4 are fixed to the inner wall of the outer casing 7c where the two pairs of magnets are opposite to each other, and the negative stiffness device specifically operates as follows:

in the device, the longitudinal moving magnet 7b1 is opposite to the longitudinal static magnet 7b2 in different poles, so the force between the two is attraction force, when the longitudinal moving magnet 7b1 is in a central symmetrical position relative to the longitudinal static magnet 7b2 on the inner wall of the outer sleeve 7c, the resultant force of the magnetic force applied to the longitudinal moving magnet 7b1 is zero, and the symmetrical position is a zero-force point. When the longitudinal moving magnet 7b1 deviates from the zero-force point, the attraction between the longitudinal moving magnet 7bq and the close longitudinal static magnet 7b2 increases, and the attraction between the longitudinal moving magnet 7b1 and the far longitudinal static magnet 7b5 decreases, so the direction of the resultant magnetic force applied to the longitudinal moving magnet 7b1 is the same as the displacement direction of the deviation from the zero-force point, namely, the negative stiffness.

Therefore, for the whole air spring system of this embodiment, the attraction force from the top longitudinal static magnet 7b2 received by the longitudinal moving magnet 7b1 before the compressed transfer device 7a descends to the zero-force point is greater than that of the bottom longitudinal static magnet 7b2, so that the direction of the resultant magnetic force received by the longitudinal moving magnet 7b1 and the transfer device 7a is upward, and the negative stiffness device 7 provides positive stiffness in the process; when the transfer device 7a is further loaded and descends to a position below the zero-force point, the attraction force from the top longitudinal static magnet 7b2 is greater than that of the bottom longitudinal static magnet 7b2, so that the longitudinal moving magnet 7b1 and the transfer device 7a are in the downward direction of the resultant magnetic force, and the negative stiffness device 7 provides negative stiffness in the process.

Similarly, the transverse static magnet 7b3 and the transverse moving magnet 7b4 are opposite in homopolar, so the force between the two is repulsive force, when the transverse moving magnet 7b3 deviates from a zero-force point, the displacement direction of the deviation zero-force point is the same as the direction of the magnetic force applied to the transverse moving magnet 7b3, namely negative rigidity, specifically, before the transverse moving magnet 7b3 descends to the zero-force point along with the pressed transmission device 7a, the transverse moving magnet 7b3 is subjected to upward repulsive force of the transverse static magnet 7b4, so the direction of the resultant magnetic force applied to the transverse moving magnet 7b3 and the transmission device 7a is upward, and therefore positive rigidity is achieved; when the transfer device 7a further bears the weight and continuously descends to the position below the zero-force point, the transverse moving magnet 7b3 receives the downward repulsive force of the transverse static magnet 7b4, so that the transverse moving magnet 7b3 and the transfer device 7a are subjected to the downward direction of the resultant magnetic force, and the negative stiffness device 7 provides negative stiffness in the process.