Magnetorheological fluid control device with wide-range damping characteristic

Abstract

The invention relates to a magnetorheological fluid control device with a wide-range damping characteristic, and belongs to the technical field of intelligent material control. Comprising a double-outlet piston rod, a combined cylinder barrel, a magnet exciting coil, an outer barrel, magnetorheological fluid, a multi-channel current source and intelligent terminal equipment. The end of the double-outlet piston rod is connected to a device to be tested, and the middle square piston is matched with the combined cylinder barrel in shape so as to push the magnetorheological fluid to flow to form damping force. The combined cylinder barrel is formed by welding and combining the two magnetic-conducting first cylinder barrel pieces and the two non-magnetic-conducting second cylinder barrel pieces, uniform control over a magnetic field is facilitated, the magnetorheological fluid obtains the more accurate magnetic field control characteristic, and the damping force control effect is improved. The excitation coil is wound in the three grooves of the combined cylinder barrel, the current of the three coils is independently controlled through the multi-channel current source and the intelligent terminal device at the same time, the damping force range is flexibly adjusted, and wide-range damping characteristic adaptation of different devices to be tested is achieved. The device is simple in structure, convenient to operate and wide in applicability.

Description

Technical Field

[0001] This invention belongs to the field of intelligent material control technology and relates to a magnetorheological fluid control device with a wide range of damping characteristics. Background Technology

[0002] In recent years, magnetorheological fluid (MRF) technology has been widely applied in various fields due to its advantages such as rapid response, high controllability, and low energy consumption. In the automotive industry, MRF shock absorbers are used in the suspension systems of high-end cars, improving ride comfort and handling by adjusting damping forces. In the construction industry, MRF dampers are used for seismic damping in bridges and high-rise buildings, adjusting damping forces in real time according to wind speed changes. In precision manufacturing, MRF technology is used for vibration control of machine tools, reducing the impact of vibration during cutting on machining accuracy and lowering part machining errors. With the continuous improvement of application demands, the market's performance requirements for MRF control devices are also increasing, requiring devices that can simultaneously adapt to the testing needs of various types of devices under test, such as automobiles, motorcycles, building components, and precision instruments.

[0003] Traditional magnetorheological fluid (MRF) control devices often use a single magnetic material (such as ordinary carbon steel) to machine the cylinder as a single piece. This structure causes the magnetic field generated by the excitation coil to spread irregularly in all directions within the cylinder, failing to concentrate its effect on the working area where the MRF is located. This uneven magnetic field distribution leads to inconsistent viscosity changes in different regions of the MRF within the cylinder. In some areas, the MRF cannot fully respond to changes in the magnetic field, resulting in significant fluctuations in the damping force. These fluctuations in damping force can cause deviations in experimental data. To compensate for the narrow damping force control range and poor magnetic field uniformity, traditional MRF control devices often require additional auxiliary structures, such as multiple sets of magnetic plates, magnetic field shields, and complex transmission mechanisms. This results in a complex overall structure, large size, and increased weight. Furthermore, the complex structure increases assembly difficulty and maintenance costs. During maintenance, the obstruction caused by the auxiliary structures makes troubleshooting difficult, severely impacting the continuity of testing.

[0004] Traditional magnetorheological fluid control devices lack versatility in their structural design. Parameters such as piston rod dimensions, cylinder volume, and damping force adjustment logic are often customized for specific types of devices under test, failing to flexibly adapt to testing requirements with varying mechanical characteristics. Furthermore, traditional devices employ relatively simplistic control methods, mostly relying on manual current adjustment to control damping force, making integration with intelligent testing systems impossible. In component testing on automated production lines, traditional devices struggle to integrate into intelligent testing processes, requiring frequent manual intervention. This not only reduces testing efficiency but also makes them susceptible to human error affecting test accuracy.

[0005] To address the shortcomings of traditional devices, the industry has undertaken a series of improvement attempts. For example, some companies have introduced dual-coil magnetorheological fluid control devices, which expand the adjustment range of magnetic field strength through the series or parallel control of two sets of coils. However, these devices still use synchronous control of the two sets of coils, making it impossible to independently adjust the current of each set of coils. The flexibility of damping force adjustment remains insufficient, making it difficult to achieve precise damping characteristic adaptation. Regarding magnetic field uniformity optimization, some research institutions have proposed a scheme of setting magnetic permeable grooves on the inner wall of the cylinder. These grooves guide the direction of the magnetic field, reducing the uniformity error of the magnetic field within the cylinder. However, this scheme requires precision machining on the inner wall of the cylinder, leading to a significant increase in manufacturing costs. Furthermore, the magnetic permeable grooves can easily cause eddies in the magnetorheological fluid during flow, increasing energy loss and affecting the stability of the damping force. In terms of structural simplification, some companies have attempted to use integrated molding technology to manufacture the cylinder and piston rod, reducing assembly steps. However, the integrated structure means that individual components cannot be replaced when damaged, and the entire unit must be replaced, increasing maintenance costs. At the same time, the integrated structure has poor heat dissipation performance, making it difficult to dissipate the heat generated by the excitation coil during operation, which leads to an increase in coil temperature and affects the coil's service life and magnetic field stability.

[0006] These challenges mean that existing magnetorheological fluid control devices cannot fully meet the market's demand for multi-scenario, high-precision, and high-efficiency testing, thus restricting the application and promotion of magnetorheological damping technology in more fields.

[0007] In conclusion, there is an urgent practical need to develop a magnetorheological fluid control device with a wide range of damping characteristics, which is of great significance for the further application and development of the current field of intelligent material control technology. Summary of the Invention

[0008] In view of this, the purpose of the present invention is to provide a magnetorheological fluid control device with a wide range of damping characteristics, to solve the problem of insufficient damping characteristic range of the magnetorheological fluid control device, and to further improve the simplicity, efficiency and other performance of the magnetorheological fluid control device.

[0009] To achieve the above objectives, the present invention provides the following technical solution: A magnetorheological fluid control device with a wide range of damping characteristics includes a combined cylinder containing magnetorheological fluid. At least three annular grooves are sequentially arranged on the outer periphery of the combined cylinder, each groove containing an excitation coil. An outer cylinder is also fitted around the outer periphery of the combined cylinder, with end caps at both ends to seal both ends of the outer cylinder and the combined cylinder. Each end cap has a through hole through which a double-ended piston rod is inserted into the combined cylinder. Both ends of the double-ended piston rod extend beyond the end caps and are connected to a device under test. A piston with a shape matching the inner diameter of the combined cylinder is located in the middle of the double-ended piston rod. The movement of the double-ended piston rod within the combined cylinder drives the magnetorheological fluid to flow, thereby generating a damping force.

[0010] Optionally, the combined cylinder is a square cylinder, which includes two sets of opposing surfaces, one set of opposing surfaces being two magnetically conductive first cylinder plates, and the other set of opposing surfaces being non-magnetically conductive second cylinder plates; the outer cylinder sleeved on the outer periphery of the combined cylinder is a square outer cylinder, and the inner diameter of the square outer cylinder matches the outer diameter of the combined cylinder; the piston in the middle of the double-outlet piston rod is a square piston whose inner diameter and shape match the combined cylinder.

[0011] Optionally, each group of excitation coils is electrically connected to an external multi-channel current source, and the current flowing through each group of excitation coils is independently controlled by the multi-channel current source to adjust the damping force range.

[0012] Optionally, the multi-channel current source is also electrically connected to the intelligent terminal device to transmit the energizing current and magnetic field information of each group of excitation coils to the intelligent terminal device, and to adjust and control the energizing current of each group of excitation coils through the instructions sent by the intelligent terminal device.

[0013] Optionally, the piston in the middle of the dual-outlet piston rod is clearance-fitted with the inner diameter of the combined cylinder, with the clearance controlled within the range of 1~3mm.

[0014] Optionally, a wire hole is provided at the bottom of the groove, and the excitation coil wire is led out from the wire hole.

[0015] Optionally, a sealing ring is provided inside the through hole.

[0016] Optionally, the end cap is also provided with an injection port and an exhaust port. The injection port is used to fill the combined cylinder with magnetorheological fluid, and the exhaust port is used to expel air from the working chamber to ensure that the magnetorheological fluid fills the entire working chamber.

[0017] Optionally, the outer cylinder is made of No. 20 steel or No. 15 steel, which together with the excitation coil forms a closed magnetic field.

[0018] Optionally, the first cylinder barrel plate is made of electrical pure iron, silicon steel sheet, low carbon steel, iron-cobalt alloy or iron-nickel alloy; the second cylinder barrel plate is made of 304 stainless steel, 316 stainless steel, titanium alloy or copper alloy.

[0019] The beneficial effects of this invention are as follows: This invention employs a unique combination of a double-piston rod, a combined cylinder, and multiple excitation coils. The simple structure of each component reduces manufacturing complexity and cost. Compared to some traditional magnetorheological fluid control devices, it avoids complex high-precision machining processes and numerous assembly steps, reducing scrap rates and costs. Through the cooperation of a multi-channel current source and intelligent terminal equipment, intelligent control of the entire device is achieved. Simply inputting corresponding control commands on the intelligent terminal equipment allows for easy control of the excitation coil's on / off state and current magnitude, enabling flexible adjustment of the damping force. The combined cylinder's segmented welding structure, with both magnetically conductive and non-magnetically conductive sections, ensures a more uniform horizontal magnetic field, resulting in more precise magnetic field control characteristics for the magnetorheological fluid and improved damping force control. Traditional magnetorheological dampers suffer from unstable damping force output due to uneven magnetic field distribution; however, this invention, through magnetic field directional control technology, ensures a uniform horizontal magnetic field distribution, thereby improving the stability and repeatability of the damping force.

[0020] This invention achieves wide-range adjustment of damping force through a three-set independently controlled excitation coil design. The damping force ranges from the minimum value when no current is applied to the maximum value when all three coils are connected, enabling continuous adjustment over a wide range. Flexible switching between single-coil, dual-coil, and triple-coil operating modes, along with fine-tuning of the current in each coil, provides a significant adjustment range from the current when no excitation coil is connected to the maximum current when all three excitation coils are simultaneously connected. This allows for wide-range adaptation to the damping characteristics of different devices under test, making it far more suitable than traditional devices. Deep integration of the multi-channel current source with the intelligent terminal device enables automated control of the damping force and real-time data monitoring. The control software of the intelligent terminal device has functions such as control strategy generation, data storage and analysis, and fault diagnosis, and can seamlessly interface with automated testing systems, integrating into intelligent testing processes.

[0021] This invention boasts advantages such as simple structure and convenient operation, achieving significant breakthroughs over existing technologies in multiple dimensions including accuracy, adaptability, operational efficiency, and stability. It not only precisely meets the high standards required for magnetorheological fluid control devices in the current field of intelligent materials control but also demonstrates significant potential for widespread application, providing a new solution for related magnetorheological damping devices.

[0022] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the magnetorheological fluid control device according to Embodiment 1 of the present invention; Figure 2 This is a cross-sectional view of the magnetorheological fluid control device according to Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the cylinder barrel according to Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the piston rod according to Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the control device for magnetorheological fluid according to Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the magnetorheological fluid control device according to Embodiment 2 of the present invention; Figure 7 This is a control schematic diagram of the magnetorheological fluid control device according to Embodiment 3 of the present invention; Figure 8 This is a schematic diagram of the control device for the magnetorheological fluid control according to Embodiment 4 of the present invention; Figure 9 This is a schematic diagram of the control device for the magnetorheological fluid control according to Embodiment 5 of the present invention; Figure 10 This is a control schematic diagram of the magnetorheological fluid control device according to Embodiment Six of the present invention; Figure 11 This is a schematic diagram of the control device for the magnetorheological fluid control device according to Embodiment 7 of the present invention.

[0024] Figure label: 1. Double-outlet piston rod, 2. Combined cylinder, 21. First cylinder plate, 22. Second cylinder plate, 3. End cap, 5. Excitation coil, 51. First excitation coil, 52. Second excitation coil, 53. Third excitation coil, 6. Outer cylinder, 7. Magnetorheological fluid, 8. Multi-channel current source, 9. Intelligent terminal equipment. Detailed Implementation

[0025] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0026] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0027] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0028] Please see Figures 1 to 11 It is a magnetorheological fluid control device with a wide range of damping characteristics, consisting of a double-outlet piston rod 1, a combined cylinder 2, an end cap 3, an excitation coil 5, an outer cylinder 6, a magnetorheological fluid 7, a multi-channel current source 8, and an intelligent terminal device 9.

[0029] The combined cylinder 2 is a square cylinder that contains magnetorheological fluid 7. At least three annular grooves are arranged sequentially on the outer periphery of the combined cylinder 2, and an excitation coil 5 is wound in each groove. An outer cylinder 6 is fitted on the outer periphery of the combined cylinder 2. End caps 3 are provided at both ends of the outer cylinder 6 to seal the outer cylinder 6 and the two ends of the combined cylinder 2. The end caps 3 are provided with through holes, through which the double-outlet piston rod 1 is inserted into the combined cylinder 2. The two ends of the double-outlet piston rod 1 extend out of the end caps 3 at both ends and are connected to the device under test through adapters. A square piston that matches the inner diameter and shape of the combined cylinder 2 is provided in the middle of the double-outlet piston rod 1. The double-outlet piston rod 1 moves inside the combined cylinder 2 to push the magnetorheological fluid 7 to flow, thereby generating a damping force.

[0030] The combined cylinder 2 is welded together from two magnetic first cylinder plates 21 and two non-magnetic second cylinder plates 22. The first cylinder plates 21 are on the left and right sides, and the second cylinder plates 22 are on the top and bottom sides, forming a square cylinder that is magnetically conductive on the left and right sides and non-magnetically conductive on the top and bottom sides. This allows the magnetic field to be controlled more uniformly in the horizontal direction, thereby enabling the magnetorheological fluid 7 to obtain more precise magnetic field control characteristics and improve the damping force control effect.

[0031] The excitation coil 5 comprises three sets of coils: a first excitation coil 51, a second excitation coil 52, and a third excitation coil 53. These coils are wound into the front, middle, and rear annular grooves of the combined cylinder 2, respectively. The current flowing through the three sets of coils can be independently and simultaneously controlled by a multi-channel current source 8, and the current and magnetic field information is transmitted to the intelligent terminal device 9. Under different mechanical characteristics of the device under test, one or more sets of coils can be turned on, and the current magnitude of each set of coils can be adjusted to flexibly adjust the damping force range. There is a large adjustment range from no current flowing through the excitation coil 5 to the maximum current when all three sets of excitation coils 5 are simultaneously turned on, achieving wide-range damping characteristic adaptation for different devices under test.

[0032] The magnetorheological fluid control device can send commands to the multi-channel current source 8 via the intelligent terminal device 9 to control the current of each channel, thereby enabling the magnetic fields generated by the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 to form multiple modes. When only one excitation coil 5 is turned on, any one of the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 can be turned on, and the current can be freely adjusted in real time from 0 to 5A. When two excitation coils 5 are turned on, the first excitation coil 51 and the second excitation coil 52, the first excitation coil 51 and the third excitation coil 53, and the second excitation coil 52 and the third excitation coil 53 can be turned on, and the current of both can be freely adjusted in real time from 0 to 5A. When three excitation coils 5 are turned on, the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 work simultaneously to generate magnetic fields, and the current of all three can be freely adjusted in real time from 0 to 5A.

[0033] The dual-outlet piston rod 1 is made of high-strength materials, such as 40Cr steel, 45 steel or 42CrMo steel, with standard mechanical interfaces at both ends, vertically penetrating the upper end cover 3 and the lower end cover 4. The middle section is a square piston structure that fits into the inner wall of the combined cylinder 2. The surface of the rod is chrome-plated to reduce the coefficient of friction with the sealing ring, thereby improving sealing performance and service life.

[0034] The side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled between 1 and 3 mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0035] The first cylinder plate 21 of the combined cylinder 2 is made of a magnetically conductive material, such as electrical pure iron, silicon steel sheet, low carbon steel, iron-cobalt alloy, or iron-nickel alloy, with a thickness of 8-12mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted horizontally, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid is located. The second cylinder plate 22 of the combined cylinder 2 is made of a non-magnetically conductive material, such as 304 stainless steel, 316 stainless steel, titanium alloy, or copper alloy, with a thickness of 8-12mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoiding waste of magnetic field energy, and improving the corrosion resistance of the cylinder. The two first cylinder plates 21 and the two second cylinder plates 22 are combined by precision welding to form a closed structure, such as laser welding, micro-arc welding, or laser-arc hybrid welding. After welding, the weld is ground to ensure that the inner wall of the cylinder is smooth, so as not to affect the movement accuracy of the piston.

[0036] The annular groove on the outer circumferential sidewall of the combined cylinder 2 has the following dimensions: depth 5~15mm, width 30~50mm, and spacing between adjacent grooves 50~70mm. The inner wall of the groove is polished to ensure tight fit with the excitation coil 5, reduce the gap between the excitation coil 5 and the combined cylinder 2, and improve the magnetic field transmission efficiency. At the same time, six 2mm diameter wire holes are provided at the bottom of the groove for the lead-out of the excitation coil 5 wires to prevent the wires from being squeezed and damaged.

[0037] The three sets of independently controllable first excitation coil 51, second excitation coil 52, and third excitation coil 53 are wound with high-temperature resistant enameled wire. The two ends of each coil are connected to the corresponding channel of the multi-channel current source 8 through wires to generate a controllable magnetic field in the combined cylinder 2. They can flexibly control the opening of one or more coils according to actual needs.

[0038] The end cap 3 is made of No. 20 steel or No. 15 steel. A polytetrafluoroethylene sealing ring is installed in the through hole in the center of the end cap that matches the double piston rod 1 to prevent the magnetorheological fluid 7 from leaking. The end cap 3 is provided with an injection port and an exhaust port. The injection port is used to fill the combined cylinder 2 with magnetorheological fluid 7, and the exhaust port is used to expel the air in the working chamber to ensure that the magnetorheological fluid 7 fills the entire working chamber.

[0039] The outer cylinder 6 is made of No. 20 steel or No. 15 steel and is sleeved on the outside of the combined cylinder 2 to protect the excitation coil 5 and the combined cylinder 2. At the same time, as a key link in the magnetic circuit, it works with the excitation coil 5 to form a closed magnetic field.

[0040] Magnetorheological fluid 7 is filled in the working chamber of the combined cylinder 2. It is prepared by mixing ferromagnetic particles, matrix and additives. It can produce significant viscosity changes under different magnetic field strengths, thereby achieving effective adjustment of damping force.

[0041] The ferromagnetic particles in the magnetorheological fluid 7 are at least one of soft magnetic materials and hard magnetic materials, such as pure iron powder, Fe3O4 or carbonyl iron powder, with a particle size range of 500~2000nm and a volume fraction of 5%~20% in the magnetorheological fluid, so as to improve the magnetorheological effect and stability of the magnetorheological fluid 7.

[0042] The matrix of magnetorheological fluid 7 is polydimethylsiloxane, silicone rubber, or polyurethane, etc.

[0043] The multi-channel current source 8 adopts a multi-channel independent output design, with each channel having a current adjustment range of 0~5A, a current accuracy of ±0.01A, and a response time of less than 10ms.

[0044] The multi-channel current source 8 is connected to the intelligent terminal device 9 via an RS485 communication interface. It can receive control commands from the intelligent terminal device 9 and simultaneously upload the real-time current data of each coil to the intelligent terminal device 9.

[0045] The intelligent terminal device 9 combines real-time magnetic field strength monitoring data and mechanical characteristic parameters of the device under test to achieve closed-loop adaptive adjustment of damping force, and has functions such as real-time data acquisition, magnetic field simulation calculation, damping force prediction, and coil control strategy generation.

[0046] The intelligent terminal device 9 includes a fault diagnosis and safety protection system. When abnormal current, excessive temperature, or sudden change in damping force is detected, the protection mechanism is automatically triggered and an alarm signal is sent.

[0047] Example 1 The magnetorheological fluid control device with wide-range damping characteristics in this embodiment can operate the current of each channel of the multi-channel current source 8 through the intelligent terminal device 9, thereby controlling the magnetic fields generated by the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 to form multiple modes. When the three excitation coils 5 are turned on, the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 work simultaneously to generate magnetic fields, and the current of each of the three can be freely adjusted in real time from 0 to 5A.

[0048] Preferably, the dual-outlet piston rod 1 is made of high-strength 40Cr steel, with standard mechanical interfaces at both ends, vertically penetrating the end caps 3 at both ends, and the middle section is a square piston structure that fits with the inner wall of the combined cylinder 2. The surface of the rod is chrome-plated to reduce the coefficient of friction with the sealing ring, thereby improving sealing performance and service life.

[0049] Preferably, the side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 2mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0050] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of electrically pure iron, a magnetically conductive material, with a thickness of 10mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted horizontally, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of 304 stainless steel, a non-magnetically conductive material, with a thickness of 10mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoiding waste of magnetic field energy, and improving the corrosion resistance of the cylinder. The two first cylinder plates 21 and the two second cylinder plates 22 are laser-welded together using a precision welding process to form a closed structure. After welding, the weld seam is ground to ensure that the inner wall of the cylinder is smooth, avoiding affecting the movement accuracy of the piston.

[0051] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 10mm, width 40mm, and spacing between adjacent grooves 60mm.

[0052] Preferably, the end cap 3 is made of No. 20 steel, the outer cylinder 6 is made of No. 20 steel, and the ferromagnetic particles of the magnetorheological fluid 7 are carbonyl iron powder with a particle size range of 1000 nm, and the volume fraction in the magnetorheological fluid 7 is 10% to improve the magnetorheological effect and stability of the magnetorheological fluid 7. The matrix of the magnetorheological fluid 7 is polydimethylsiloxane.

[0053] Preferably, the multi-channel current source 8 adopts a three-channel independent output design, with each channel having a current adjustment range of 0~5A, a current accuracy of ±0.01A, and a response time of less than 10ms. The multi-channel current source 8 is connected to the intelligent terminal device 9 via an RS485 communication interface, and can receive control commands from the intelligent terminal device 9, while simultaneously uploading real-time current data of each coil to the intelligent terminal device 9.

[0054] The intelligent terminal device 9 combines real-time magnetic field strength monitoring data with the mechanical characteristic parameters of the device under test to achieve closed-loop adaptive adjustment of the damping force. It has functions such as real-time data acquisition, magnetic field simulation calculation, damping force prediction, and coil control strategy generation. The intelligent terminal device 9 includes a fault diagnosis and safety protection system. When abnormal current, excessive temperature, or sudden change in damping force is detected, the protection mechanism is automatically triggered and an alarm signal is sent.

[0055] Example 2 The difference between this embodiment and Embodiment 1 is that the magnetorheological fluid 7 control device in this embodiment can operate the current of each channel of the multi-channel current source 8 through the intelligent terminal device 9, thereby controlling the magnetic fields generated by the first excitation coil 51, the second excitation coil 52, and the third excitation coil 53 to form multiple modes. In this embodiment, two excitation coils 5 are turned on, and the first excitation coil 51 and the second excitation coil 52 are selected to be turned on. The current of both can be freely adjusted in real time from 0 to 5A.

[0056] Preferably, the double-outlet piston rod 1 is made of high-strength material No. 45 steel. The side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 1mm to prevent the piston from rotating during the movement, ensuring the stable flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increasing the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0057] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of magnetically conductive silicon steel sheet with a thickness of 8mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of non-magnetically conductive 316 stainless steel with a thickness of 8mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder. The two first cylinder plates 21 and the two second cylinder plates 22 are combined by precision welding using micro-arc welding to form a closed structure. After welding, the weld is ground to ensure that the inner wall of the cylinder is smooth and to avoid affecting the movement accuracy of the piston.

[0058] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 5mm, width 30mm, and spacing between adjacent grooves 50mm.

[0059] Preferably, the end cap 3 is made of No. 15 steel, the outer cylinder 6 is made of No. 15 steel, and the ferromagnetic particles of the magnetorheological fluid 7 are Fe3O4 with a particle size range of 500 nm, and the volume fraction in the magnetorheological fluid 7 is 5%, in order to improve the magnetorheological effect and stability of the magnetorheological fluid 7. The matrix of the magnetorheological fluid 7 is silicone rubber, etc.

[0060] Preferably, the multi-channel current source 8 adopts a two-channel independent output design, with each channel having a current adjustment range of 0~5A, a current accuracy of ±0.01A, and a response time of less than 10ms.

[0061] Example 3 The difference between this embodiment and the above embodiment is that, in this embodiment, when the two excitation coils 5 are turned on, the first excitation coil 51 and the third excitation coil 53 are turned on, and the current of both can be freely adjusted in real time from 0 to 5A.

[0062] Preferably, the dual-outlet piston rod 1 is made of high-strength 42CrMo steel. The side length of the square piston of the dual-outlet piston rod 1 matches the inner side length of the combined cylinder 2, with the gap controlled at 3mm. This prevents the piston from rotating during movement, ensures the stability of the flow direction of the magnetorheological fluid 7 within the combined cylinder 2, and increases the contact area between the piston and the magnetorheological fluid 7, thereby improving the sensitivity of damping force adjustment.

[0063] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of low-carbon steel with a magnetic permeability and a thickness of 12mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of titanium alloy with a non-magnetic permeability and a thickness of 12mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder. The two first cylinder plates 21 and the two second cylinder plates 22 are combined by laser-arc composite welding using precision welding technology to form a closed structure. After welding, the weld is ground to ensure that the inner wall of the cylinder is smooth and to avoid affecting the movement accuracy of the piston.

[0064] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 15mm, width 50mm, and spacing between adjacent grooves 70mm.

[0065] Preferably, the ferromagnetic particles of the magnetorheological fluid 7 are pure iron powder with a particle size range of 2000 nm, and their volume fraction in the magnetorheological fluid 7 is 20%, in order to improve the magnetorheological effect and stability of the magnetorheological fluid 7. The matrix of the magnetorheological fluid 7 is polyurethane.

[0066] Preferably, the multi-channel current source 8 adopts a two-channel independent output design, with each channel having a current adjustment range of 0~5A, a current accuracy of ±0.01A, and a response time of less than 10ms.

[0067] Example 4 The difference between this embodiment and the above embodiment is that, in this embodiment, when the two excitation coils 5 are turned on, the second excitation coil 52 and the third excitation coil 53 are turned on, and the current of both can be freely adjusted in real time from 0 to 5A.

[0068] Preferably, the side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 1.5mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0069] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of a magnetically conductive iron-cobalt alloy with a thickness of 9mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of a non-magnetically conductive copper alloy with a thickness of 9mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder.

[0070] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 7.5mm, width 35mm, and spacing between adjacent grooves 55mm.

[0071] Preferably, the multi-channel current source 8 adopts a two-channel independent output design, with each channel having a current adjustment range of 0~5A, a current accuracy of ±0.01A, and a response time of less than 10ms.

[0072] Example 5 The difference between this embodiment and the above embodiment is that in this embodiment, one excitation coil 5 is turned on, the first excitation coil 51 is turned on, and the current can be freely adjusted in real time from 0 to 5A.

[0073] Preferably, the side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 2.5mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0074] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of a magnetically conductive iron-nickel alloy with a thickness of 11mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of a non-magnetically conductive titanium alloy with a thickness of 11mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder.

[0075] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 12.5mm, width 45mm, and spacing between adjacent grooves 65mm.

[0076] Example 6 The difference between this embodiment and the above embodiment is that only one excitation coil 5 is turned on, and the second excitation coil 52 is turned on. The current can be freely adjusted in real time from 0 to 5A.

[0077] Preferably, the side length of the square piston of the dual-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 2.8mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0078] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of electrically pure iron, a magnetically conductive material, with a thickness of 9.8 mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of 304 stainless steel, a non-magnetically conductive material, with a thickness of 9.8 mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder.

[0079] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 8mm, width 38mm, and spacing between adjacent grooves 58mm.

[0080] Example 7 The difference between this embodiment and the above embodiment is that only one excitation coil 5 is turned on in this embodiment, and the third excitation coil 53 is turned on, and the current can be freely adjusted in real time from 0 to 5A.

[0081] Preferably, the side length of the square piston of the double-outlet piston rod 1 matches the inner side length of the combined cylinder 2, and the gap is controlled at 2.2mm to prevent the piston from rotating during movement, ensure the stability of the flow direction of the magnetorheological fluid 7 in the combined cylinder 2, and increase the contact area between the piston and the magnetorheological fluid 7 to improve the adjustment sensitivity of the damping force.

[0082] Preferably, the first cylinder plate 21 of the combined cylinder 2 is made of a magnetically conductive iron-nickel alloy with a thickness of 10.2 mm. Its main function is to guide the magnetic field generated by the excitation coil 5 to be transmitted in the horizontal direction, ensuring that the magnetic field is concentrated on the working area where the magnetorheological fluid 7 is located. Preferably, the second cylinder plate 22 of the combined cylinder 2 is made of a non-magnetically conductive copper alloy with a thickness of 10.2 mm. Its main function is to block the diffusion of the magnetic field in the vertical direction, avoid waste of magnetic field energy, and improve the corrosion resistance of the cylinder.

[0083] Preferably, the dimensions of the annular groove on the outer peripheral sidewall of the combined cylinder 2 are: depth 12mm, width 42mm, and spacing between adjacent grooves 62mm.

[0084] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A magnetorheological fluid control device with a wide range of damping characteristics, characterized in that: The system includes a combined cylinder (2) containing magnetorheological fluid (7). At least three annular grooves are arranged sequentially on the outer periphery of the combined cylinder (2), and an excitation coil (5) is wound in each groove. An outer cylinder (6) is also fitted on the outer periphery of the combined cylinder (2). End caps (3) are provided at both ends of the outer cylinder (6) to seal the outer cylinder (6) and the two ends of the combined cylinder (2). The end caps (3) are provided with through holes, and a double-outlet piston rod (1) is inserted into the combined cylinder (2) through the through holes. The two ends of the double-outlet piston rod (1) extend out of the end caps (3) at both ends and are connected to the device to be tested. A piston that matches the inner diameter and shape of the combined cylinder (2) is provided in the middle of the double-outlet piston rod (1). The double-outlet piston rod (1) moves in the combined cylinder (2) to push the magnetorheological fluid (7) to flow, thereby forming a damping force.

2. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: The combined cylinder (2) is a square cylinder, which includes two sets of opposing surfaces. One set of opposing surfaces consists of two magnetically conductive first cylinder plates (21), and the other set of opposing surfaces consists of non-magnetically conductive second cylinder plates (22). The outer cylinder (6) sleeved on the outer periphery of the combined cylinder (2) is a square outer cylinder (6), and the inner diameter of the square outer cylinder (6) matches the outer diameter of the combined cylinder (2). The piston in the middle of the double-outlet piston rod (1) is a square piston whose inner diameter and shape match those of the combined cylinder (2).

3. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: Each of the excitation coils (5) is electrically connected to an external multi-channel current source (8). The current of each excitation coil (5) is independently controlled by the multi-channel current source (8) to adjust the range of damping force.

4. The magnetorheological fluid control device with wide-range damping characteristics according to claim 3, characterized in that: The multi-channel current source (8) is also electrically connected to the smart terminal device (9) to transmit the energizing current and magnetic field information of each group of excitation coils (5) to the smart terminal device (9), and adjust and control the energizing current of each group of excitation coils (5) through the instructions sent by the smart terminal device (9).

5. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: The piston in the middle of the double-outlet piston rod (1) is fitted with the inner diameter of the combined cylinder (2) with a clearance control within the range of 1~3mm.

6. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: A wire hole is provided at the bottom of the groove, and the wire of the excitation coil (5) is led out from the wire hole.

7. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: A sealing ring is provided inside the through hole.

8. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: The end cap (3) is also provided with an injection port and an exhaust port. The injection port is used to fill the combined cylinder (2) with magnetorheological fluid (7), and the exhaust port is used to discharge the air in the working chamber to ensure that the magnetorheological fluid (7) fills the entire working chamber.

9. The magnetorheological fluid control device with wide-range damping characteristics according to claim 1, characterized in that: The outer cylinder (6) is made of No. 20 steel or No. 15 steel, and together with the excitation coil (5), it forms a closed magnetic field.

10. The magnetorheological fluid control device with wide-range damping characteristics according to claim 2, characterized in that: The first cylinder plate (21) is made of electrical pure iron, silicon steel, low carbon steel, iron-cobalt alloy or iron-nickel alloy; the second cylinder plate (22) is made of 304 stainless steel, 316 stainless steel, titanium alloy or copper alloy.

Images