Double-cavity oil-gas separation type variable cross-section magnetorheological damper

Abstract

The invention discloses a double-cavity oil-gas separation type variable cross-section magneto-rheological damper which is innovated and improved on the basis of a double-cavity oil-gas separation type self-resetting magneto-rheological damper. In particular to a variable cross-section moving device capable of controlling the cross-section area, which comprises the design of a cylinder wall interlayer, temperature control in the cylinder wall interlayer and application of a demagnetizing coating. The variable cross-section moving device is related to the current, and related feedback is carried out according to the change of the magnitude of the current; a temperature control facility designed in the interlayer design is related to the temperature detected by a temperature sensor, and if the detected temperature exceeds a threshold range, corresponding measures are taken for temperature control in the cylinder body wall; the demagnetizing coating is only an innovative application of a demagnetizing material in the invention.

Description

Technical Field

[0001] The present invention relates to the technical field of earthquake resistance in earthquake zones, and in particular to a double-cavity oil-gas separation type variable-section magnetorheological damper. Background Art

[0002] Single-chamber MRD, i.e., single-chamber magnetorheological damper, has only one chamber inside to contain magnetorheological fluid. The damping characteristics of magnetorheological fluid can be changed by changing the magnetic field strength, thereby changing the viscosity and damping force of magnetorheological fluid to achieve the purpose of controlling the damping force. However, the traditional single-chamber MRD has temperature sensitivity and precipitation problems, which will affect the mechanical properties, thereby affecting the stability and durability of the entire system. Therefore, in order to effectively separate oil and gas, reduce the influence of temperature on MR fluid, avoid particle precipitation, and improve the stability and durability of magnetorheological damper, some people have proposed various improvement schemes on the existing technology, such as: cylindrical double-chamber oil-gas separation magnetorheological damper and double-chamber oil-gas separation self-resetting magnetorheological damper, but they are greatly affected by temperature. Too high temperature will affect the performance of magnetorheological fluid, too low temperature will reduce the fluidity of magnetorheological fluid, and even solidify. At the same time, due to the degradation of magnetorheological fluid caused by long-term electromagnetic field and temperature change, the service life is shortened, and in the environment of strong electromagnetic interference and high and low temperatures, it will affect the normal operation of magnetorheological damper.

[0003] Therefore, it is necessary to provide a new type of magnetorheological damper to increase the service life and improve the environmental adaptability. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to solve the following technical problems: based on the research of a double-chamber oil-gas separation self-resetting magnetorheological damper, a new double-chamber oil-gas separation variable-section magnetorheological damper is provided, a variable-section moving device connected to a sensing device is used to increase the service life of the magnetorheological damper, and an inlaid interlayer method is used to reduce the influence of temperature on the performance, and at the same time, magnetic plating is added or subtracted on the inner wall of the magnetorheological damper to reduce sensitivity to electromagnetic fields.

[0005] In order to solve the above problems, some advantages of the double-chamber oil-gas separation self-resetting magnetorheological damper used in the present invention are first introduced here:

[0006] First, the dual-chamber design of the dual-chamber oil-gas separation technology can effectively separate oil and gas while preventing particle precipitation, thereby improving the stability and durability of the damper. Secondly, the electromagnetic iron is energized to generate a magnetic field, which changes the resistance of the piston hole by absorbing the iron powder in the magnetorheological fluid in the cylinder, thereby adjusting the damping force.

[0007] The specific technical solutions used in the present invention are as follows:

[0008] On the one hand, the purpose of controlling the cross-sectional area of ​​the cylinder is achieved by adding a mobile device with a controllable area at the bottom of the cylinder. At the same time, the operation of the variable cross-sectional mobile device is controlled by the current passed into the electromagnet, that is, the current in the connecting line. If the current decreases, the mobile device rises a certain area according to the difference in the current, increases the damping force, and improves the shock absorption effect; otherwise, the damping force is reduced. The cross-sectional area moved by the variable cross-sectional mobile device passes through the PLC matrix, and the force that the variable cross-sectional mobile device needs to provide is obtained according to the change in the current, thereby operating each module of the variable cross-sectional mobile device.

[0009] Secondly, by thickening the cylinder wall so that the interlayer can be embedded, temperature control facilities are added therein and used as a thermal insulation layer to reduce the effect of external temperature on the performance of the magnetorheological fluid under different temperatures.

[0010] Furthermore, if the temperature sensor senses that the temperature is too high or too low, it will trigger a system instruction: if the temperature is lower than the preset temperature threshold, the heater will be started until the temperature returns to the preset range; if the temperature is higher than the preset temperature threshold, an appropriate amount of coolant will be added.

[0011] Thirdly, a copper wire mesh wrapped with aluminum foil Mylar is added to the inner wall of the cylinder for coating to reduce the influence of strong electromagnetic fields on the magnetorheological fluid, and the properties of the demagnetizing material are used to enhance the device's resistance to strong electromagnetic fields.

[0012] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides a device for controlling the cross-sectional area of ​​the cylinder body, which more effectively controls the magnitude of the damping force and reduces the reduction in service life caused by excessive use; the device adopts a method similar to that of a thermos cup, increases the controllability of temperature and reduces the influence of temperature on the performance of the device; the device optimizes the interior of the cylinder body and uses a coating of demagnetizing material to reduce the influence of strong electromagnetic fields on the performance of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the structure of the device;

[0014] Figure 2 for Figure 1 A schematic longitudinal section of the middle piston assembly 2;

[0015] Figure 3 for Figure 1 A schematic diagram of the structure of the moving device in the middle cylinder 1;

[0016] Figure 4 for Figure 1 A schematic diagram of the cross-sectional structure of a portion of the cylinder wall of the middle cylinder 1;

[0017] Figure 5It is a plan view of the coating on the inner wall of the cylinder;

[0018] Figure 6 This is a schematic diagram of temperature control by computer intelligent control system;

[0019] In the figure: 1-cylinder body; 2-piston assembly; 3-connecting line; 4-piston rod; 5-first flow meter; 6-first throttle valve; 7-oil inlet pipe; 8-second flow meter; 9-air nozzle; 10-liquid cylinder; 11-oil and gas partition; 12-magnetorheological fluid; 13-second throttle valve; 14-return oil pipe; 15-piston hole; 16-electromagnet; 17-variable cross-section moving system; 18-heater; 19-temperature sensor; 20-aluminum foil Mylar; 21-copper wire mesh. DETAILED DESCRIPTION

[0020] To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings:

[0021] During operation, when it is necessary to adjust the damping force of the piston assembly 2 downward, the external power supply is connected through the connecting line 3 and the electromagnet 16 is energized. The magnetic field generated by the electromagnet will adsorb the iron powder in the magnetorheological fluid 12 in the cylinder body 1, thereby forming a certain resistance at the piston hole 15, increasing the resistance encountered by the piston assembly 2 when moving inside the cylinder body. By adjusting the current input to the electromagnet 16, the magnetic field strength can be changed, thereby accurately adjusting the damping force and improving the shock absorption effect. Conversely, reducing the current can reduce the damping force; at the same time, sensing the change in current, the variable cross-section moving device 17 changes the cross-sectional size and volume in the cylinder body 1 according to the size of the current change value, so as to share the damping force of the magnetorheological fluid 12 on the piston assembly 2. The force provided by the variable cross-section moving device 17 is affected by the current, that is, the current and the force provided by the variable cross-section moving system 17 have the following relationship:

[0022]

[0023] Among them, ɑ1 is a constant related to temperature,

[0024] ɑ2--The degree of influence of the size of the device on the damping force,

[0025] ɑ3--Corrected constant,

[0026] B--magnetic field strength,

[0027] I--the current supplied to the variable cross-section moving device 17,

[0028] S--Cross-sectional area of ​​cylinder 1,

[0029] ρ--density of electromagnetic fluid,

[0030] g--acceleration due to gravity,

[0031] h--the height of the electromagnetic fluid in cylinder 1.

[0032] The cylinder body 1 is provided with an oil inlet pipe 7 and an oil return pipe 14, which are connected to the liquid cylinder 10 and are filled with magnetorheological fluid 12. When the piston assembly 2 is pressed downward, the piston hole 15 becomes narrower due to the accumulation of iron powder, which causes the magnetorheological fluid 12 in the cylinder body to flow into the liquid cylinder 10 through the first throttle valve 6 in one direction. This process can be monitored by the second flowmeter 8. When the piston assembly 2 moves upward, the magnetorheological fluid 12 in the liquid cylinder 10 flows into the cylinder body 1 in the reverse direction through the second throttle valve 13. This process is monitored by the first flowmeter 5. The damping resistance value of the piston assembly when moving upward and downward is monitored and controlled in real time through the two flowmeters, thereby optimizing the performance of the damper. The liquid cylinder 10 is filled with gas of a certain pressure, which is separated from the magnetorheological fluid 12 by the oil-gas partition 11. When the piston assembly 2 moves downward, the gas is compressed to provide a certain resistance. When the piston assembly 2 moves upward, the gas expands and pushes the piston assembly 2 to reset. The air nozzle 9 is used to balance the pressure when the pressure in the liquid cylinder 10 is unstable.

[0033] Specifically, Figure 1 As shown, during operation, when it is necessary to adjust the damping force of the piston assembly 2 downward, the external power supply is connected through the connecting line 3 and the electromagnet 16 is energized. The magnetic field generated by the electromagnet 16 will adsorb the iron powder in the magnetorheological fluid 12 in the cylinder 1. At the same time, the formation of the variable cross-section is controlled by the PLC matrix. The change in current will cause feedback from the variable cross-section moving system, thereby forming a certain resistance at the piston hole 15, increasing the resistance encountered by the piston assembly 2 when moving inside the cylinder.

[0034] Specifically, when the piston rod 4 and the piston assembly 2 move upward, a larger current (for example, 1000 mA) is released, and the variable-section moving system 17 descends, and when descending, a smaller current (for example, 500 mA) is released, and the variable-section moving system 17 rises, thereby differentially controlling the upward and downward damping forces.

[0035] Furthermore, the temperature sensor 19 in the cylinder wall senses the change of temperature T, and the heater 18 is powered on for heating when the temperature is lower than 20° C., and coolant is added when the temperature is higher than 30° C. This process is controlled by a computer intelligent control system.

[0036] At the same time, it is assumed that the heating time is determined by the time required for the temperature sensor 19 to return to the specified temperature range; further, the weight M of the coolant added through the coolant inlet is related to the temperature, that is:

[0037]

[0038] M--the weight of the coolant added,

[0039] ρ--density of coolant,

[0040] S--Cylinder 1 container wall interlayer cross-sectional area,

[0041] h--the height of cylinder 1,

[0042] σ--correction constant.

[0043] Furthermore, the copper wire mesh 21 sandwiched between two layers of aluminum foil Mylar 20 is as follows: Figure 5 The copper wire mesh 21 is an equihexagonal layer, and the coating is adhered to the inner wall of the cylinder body. This is a demagnetizing layer, and its demagnetization can reduce the influence of strong electromagnetic fields on the magnetorheological fluid.

[0044] Finally, it should be noted that: this invention is an innovative optimization and improvement based on the dual-chamber oil-gas separation self-resetting magnetorheological damper, and some of the methods and materials used in the improvement can be changed.

Claims

1. A dual-chamber oil-gas separation variable cross-section magnetorheological damper, comprising a cylinder body (1) and a liquid cylinder (10), characterized in that: The cylinder body (1) is thicker than a normal cylinder body, and a cavity is provided inside the side wall of the cylinder body (1). A heater (18) and an inlet for adding a coolant are installed inside the cavity. Whether the heater (18) and the coolant inlet are operated or not is controlled by a temperature sensor (19) on the inner wall of the cylinder body (1); the temperature sensor (19) is a normal temperature sensor, which is arranged on the inner wall of the cylinder body (1); The liquid cylinder (10) is another cylinder body independent of the cylinder body (1); an oil-gas partition (11) is arranged inside the liquid cylinder (10); a gas nozzle (9) is arranged on the top of the liquid cylinder (10); magnetorheological fluid (12) is installed inside the cylinder body (1) and the cylinder body (10); the circulation of the magnetorheological fluid (12) between the two cylinders is realized through a first throttle valve (6) and a second throttle valve (13); the first throttle valve (6) and the second throttle valve (13) are respectively arranged on an oil inlet pipe (7) and an oil return pipe (14); the oil inlet pipe (7) and the oil return pipe (14) are used to connect the cylinder body (1) and the liquid cylinder (10).

2. A dual-chamber oil-gas separation variable cross-section magnetorheological damper according to claim 1, characterized in that; A variable-section moving device (17) is provided at the bottom of the cylinder body (1); the variable-section moving device (17) is used to change the cross-sectional area of ​​the bottom surface of the movable cylinder body (1); the variable-section moving device (17) is provided at the other half bottom surface of the cylinder body (1) away from the liquid cylinder (10), and only controls this half cross section; the control of the half cross section by the variable-section moving device (17) is PLC matrix control; the variable-section moving device (17) divides the half cross section it controls into a plurality of modules as an output matrix of the PLC matrix control; the rising and falling systems of the variable-section moving device (17) are connected to the connecting line (3); the current change introduced by the connecting line (3) is the input matrix of the PLC matrix; the connecting line (3) is provided inside the piston rod (4) and connected to the piston assembly (2).

3. A dual-chamber oil-gas separation variable cross-section magnetorheological damper according to claim 1, characterized in that; The invention comprises a demagnetizing coating, wherein the magnetic materials used in the coating are aluminum foil Mylar (20) and a copper wire mesh (21), wherein the copper wire mesh (21) is a mesh composed of a plurality of regular hexagonal copper wires, and the aluminum foil Mylar (20) wraps the copper wire mesh (21) inside and is tightly fitted and adhered to the inner wall of a cylinder body (1).

Images