CN106015437B - A kind of rank power transformation MR damper - Google Patents

Abstract

The present invention relates to a kind of rank power transformation MR damper, belong to mechanical oscillation engineering field.The rank power transformation MR damper realizes that the rank of Coulomb damping power becomes output, obtains default damping force, carry out effective vibration damping by changing the distributed controll of magnetic circuit response length its effective magnetic circuit on off operating mode.Used piston has multistage electromagnetic circuit, and the inner cylinder tube section of magnetic circuit is connected by permeability magnetic material cylinder barrel with non-magnet material cylinder barrel to be formed.This rank power transformation MR damper have design it is simple, using the with strong points, damping property such as stability is high.

Description

A step-variable electromagnetic rheological damper

technical field

The invention relates to a magneto-rheological vibration control technology, in particular to a step-variable electromagnetic-rheological damper.

Background technique

Magneto-rheological fluid is a stable suspension formed by dispersing and melting non-colloidal fine particles in an insulating carrier liquid, and its rheological behavior can be controlled with the change of an external magnetic field. It can instantly transform from a free-flowing liquid under the action of an external magnetic field It is semi-solid or even solid, showing strong controllable rheological properties. The magnetorheological damper is a most promising semi-active control device developed by using the rheological characteristics of magnetorheological fluid. It has both the reliability of passive control and the adaptability of active control, and compared with active control Low energy consumption, wide dynamic range, fast response, low energy consumption, simple mechanical structure, strong environmental robustness, easy to combine with microcomputer control and other outstanding advantages. Magnetorheological dampers have been widely used in vibration control systems, such as vehicle suspension systems, aircraft landing gear systems, building earthquake protection systems, cable-stayed bridge protection systems, medical rehabilitation systems and other fields.

In addition to the magnetorheological damper, the intelligent vibration control system composed of magnetorheological dampers also needs to be equipped with external devices such as power supplies, sensors, and controllers. A power source is required to adjust the rheological damping properties of the magnetorheological fluid in the magnetorheological damper, the sensor to test the structural response, and the controller to calculate the control commands. In practical engineering applications, the existence of sensors and controllers will make the entire vibration control system relatively complex, and the system stability is relatively low, and the system cost is relatively high.

The magneto-rheological damper is developing towards a more intelligent, reliable and stable direction. In order to meet the needs of the actual engineering application environment, in recent years, the design idea of integrating some independent functional modules into the magnetorheological damper has gradually been accepted by people. focus on. That is, the energy harvesting device that converts the external mechanical vibration energy into electric energy is used to meet the electric energy demand of the magnetorheological damper, forming a self-powered magnetorheological damper system. The system uses the energy harvesting device to collect external vibration energy, and the collected The electric energy is directly supplied to the magneto-rheological damper to realize automatic damping adjustment. However, this type of self-powered magneto-rheological damper system has some shortcomings, usually as follows: (1) the collected electric energy is limited; (2) at high speed, the total damping force is large, correspondingly accompanied by large viscous damping force and large Coulomb damping force At the same time, at low speeds, the damping force is small.

Contents of the invention

The technical problem to be solved by the present invention is to provide an electromagnetic rheological damper with stable performance and step-change damping force.

The technical solution adopted by the present invention to solve its technical problems is:

A step-variable electromagnetic rheological damper, comprising a non-magnetic outer cylinder, a non-magnetic inner cylinder, a magnetic inner cylinder, a piston, a piston rod, an excitation coil, a guiding device, a magnetorheological fluid, a sealing ring, end caps and power supply. The non-magnetic inner cylinder and the magnetic inner cylinder are set in the non-magnetic outer cylinder in turn, and the non-magnetic inner cylinder and the magnetic inner cylinder are fixedly connected; the piston rod is fixedly connected with the piston, and the excitation coil is in order Wound on the piston, and the winding method of the adjacent excitation coil satisfies that the direction of the equivalent magnetic field of the same name generated by it is opposite. The lead wire of the excitation coil is drawn out through the inner hole of the piston rod and connected to the power supply.

The piston used is distributed with multi-level excitation coils. Under the condition of power on, the magnetic field generated by each level of excitation coil forms a closed magnetic circuit along the piston head, the annular damping channel gap and the inner cylinder wall. The piston is in the non-magnetic inner cylinder section. Since the inner cylinder in the magnetic circuit is not magnetically conductive, the magnetic circuit corresponding to the excitation coil of the corresponding level is not conductive, so that the magnetorheological fluid in this section of the damping channel cannot be activated, showing general The characteristics of the fluid; the piston is in the magnetically conductive inner cylinder section. Due to the magnetic permeability of the inner cylinder in the magnetic circuit, the magnetic circuit corresponding to the excitation coil of the corresponding level is conducted, so that the magnetorheological fluid in this section of the damping channel shows a certain rheological properties. Therefore, according to the application requirements, the distribution of the magnetic circuit response length is adjusted by changing the axial length of the non-magnetic inner cylinder and the magnetic inner cylinder, so as to control the effective magnetic circuit on-off of the stepped electromagnetic rheological damper. state, adjust the rheological characteristics of the magnetorheological fluid in the corresponding damping channel, realize the step-change output of the Coulomb damping force of the magnetorheological damper, obtain the preset damping force, and effectively reduce vibration.

The axial effective length of the magnetically conductive inner cylinder is not less than the axial effective length of the piston.

The non-magnetic inner cylinder is made of light non-magnetic material, such as aluminum alloy, high molecular polymer, and the magnetic inner cylinder is made of magnetic material with high magnetic permeability, such as electrical pure iron. A certain amount of magnetorheological fluid is filled in the nonmagnetic inner cylinder and the magnetic inner cylinder.

The current value provided by the power supply can be adjusted off-line, and is determined as a constant value before each operation of the magneto-rheological damper.

The piston rod and the piston move linearly along the axis of the cylinder barrel under the action of the guide device.

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

The variable electromagnetic rheological damper of this stage is powered by a power supply, and the power supply can be adjusted offline according to the application requirements, and the distribution of the magnetic circuit response length can be adjusted by changing the axial effective length of the non-magnetic inner cylinder and the magnetic inner cylinder to obtain a predetermined value. The ideal step-varying Coulomb damping force is assumed. This stage variable electromagnetic rheological damper does not need sensing and control modules, has a simple structure design, low cost, and relatively high system application stability, and is especially suitable for the vibration reduction requirements of large shock vibration structures.

Description of drawings

Fig. 1 structural principle diagram of the present invention

Explanation of reference signs in the figure: non-magnetic outer cylinder 1, non-magnetic inner cylinder 2, magnetic inner cylinder 3, piston 4, piston rod 5, excitation coil 6, guide device 7, magnetorheological fluid 8 , Seal ring 9, end cap 10, power supply 11.

Fig. 2 The output relation diagram of Coulomb damping force and piston stroke of electromagnetic rheological damper.

detailed description

Fig. 1 is a schematic diagram of the structure of the present invention, the present invention is a step-change electromagnetic rheological damper, comprising a non-magnetic outer cylinder 1, a non-magnetic inner cylinder 2, a magnetic inner cylinder 3, a piston 4, Piston rod 5, excitation coil 6, guide device 7, magnetorheological fluid 8, sealing ring 9, end cover 10, power supply 11.

The non-magnetic inner cylinder 2 and the magnetic inner cylinder 3 are fixed in the non-magnetic outer cylinder 1 as the inner cylinder, wherein the non-magnetic outer cylinder 1 and the non-magnetic inner cylinder 2 are made of aluminum alloy Material, magnetic conduction inner cylinder barrel 3 select electrician pure iron DT4 for use. The piston 4 is made of electric pure iron DT4, and is fixedly connected with the piston rod 5. Seven sets of excitation coils 6 are wound on the corresponding piston 4 in an orderly manner. Magnetorheological fluid 8 is distributed in the non-magnetic inner cylinder 2 and the magnetic inner cylinder 3 .

The axial linear movement of the piston 4 will force the magneto-rheological fluid 8 to flow through the damping passages between the piston 4 and the non-magnetic inner cylinder 2 and the magnetic inner cylinder 3 . The relative position between the piston 4 and the non-magnetic inner cylinder 2 and the magnetic inner cylinder 3 will determine the output Coulomb damping force of the magneto-rheological damper. The power supply 11 is used to provide a constant current to the magnetorheological damper. When the position of the piston 4 is located at one end of the inner end cover of the cylinder, and the energized excitation coil 6 is distributed in a section of the non-magnetic inner cylinder 2, in this state, due to The non-magnetic inner cylinder 2 is not magnetically conductive, so that the magnetic field generated by each stage of the excitation coil 6 is distributed along the gap between the piston head and the annular damping channel and cannot form a closed magnetic circuit. The magnetorheological fluid 8 in the corresponding damping channel The rheology of the magneto-rheological damper is weak, so that the magneto-rheological damper cannot generate the corresponding Coulomb damping force; as the piston moves down the cylinder axis, when the stroke of the piston meets the first-level excitation coil, the magnetic field generated along the piston head, ring When the damping channel gap and the magnetically conductive inner cylinder 3 form a closed magnetic circuit, the magnetorheological fluid in the damping channel exhibits a certain yield stress under the action of the magnetic field, and the magnetorheological damper generates a corresponding Coulomb damping force. As the downward stroke of the piston 4 increases, the magnetic field generated by the multi-stage excitation coil 6 successively forms a closed magnetic circuit along the piston head, the annular damping channel gap and the magnetically conductive inner cylinder 3, so that the magnetorheological damper accumulates Corresponding Coulomb damping force is generated, wherein, the relationship between the Coulomb damping force of the magneto-rheological damper and the downstroke of the piston 4 is shown in Figure 2. , its Coulomb damping force increases stepwise.

According to the Coulomb damping force distribution of the magneto-rheological damper, it can be seen that the magnetorheological damper is relatively suitable for the application of impact vibration reduction.

Claims (4)

1. a kind of rank power transformation MR damper, including non-magnetic outer cylinder (1), non-magnetic inner cylinder tube (2), magnetic conduction inner cylinder tube (3), piston (4), piston rod (5), magnet exciting coil (6), guider (7), magnetic flow liquid (8), sealing ring (9), end cap (10), Power supply (11)；

Connection between above-mentioned each component：

It is set with non-magnetic inner cylinder tube (2) and magnetic conduction inner cylinder tube (3) in non-magnetic outer cylinder (1), non-magnetic inner cylinder tube (2) and leads There is magnetic flow liquid in magnetic inner cylinder tube (3)；Piston rod (5) is fixedly connected with piston (4), and magnet exciting coil (6) is wrapped in piston in order (4) on, magnet exciting coil (6) lead is drawn by the endoporus of piston rod (5), and is connected with power supply (11)；It is characterized in that：

Used piston (4) is multistage electromagnetic circuit, by changing non-magnetic inner cylinder tube (2) and magnetic conduction inner cylinder tube (3) axially The distribution of effective length regulation magnetic circuit response series, the effective magnetic circuit on off operating mode of rank power transformation MR damper is controlled with this, real The rank of existing Coulomb damping power becomes output, obtains default damping force, carries out effective vibration damping.

A kind of 2. rank power transformation MR damper according to claim 1, it is characterised in that the non-magnetic inner cylinder tube (2) Smoothly it is fixedly connected with magnetic conduction inner cylinder tube (3), non-magnetic inner cylinder tube (2) uses lightweight non-magnet material, and magnetic conduction inner cylinder tube (3) is adopted With the permeability magnetic material of high magnetic permeability.

3. a kind of rank power transformation MR damper according to claim 1, it is characterised in that the power supply (11) is provided Current value can adjust offline, and each MR damper work before be defined as a constant.

4. a kind of rank power transformation MR damper according to claim 1, it is characterised in that the magnetic conduction inner cylinder tube (3) Axial effective length is not less than the axial effective length of piston (4).