245 results about "Magneto rheological damper" patented technology

The invention relates to a five-dimensional vibration isolation device which is suitable for equipment arranged on a dynamic carrier. Aiming at the problem of five-dimensional vibration of the equipment on the dynamic carrier, one hybrid mechanism-based vibration isolation platform is arranged between an equipment mounting platform and a carrier connecting platform to realize five-dimensional vibration isolation. The vibration isolation platform consists of the equipment mounting platform (1), a middle platform (2), the carrier connecting platform (5), six branched chains comprising vibration isolation subsystems and a constraint branch containing no vibration isolation subsystem, so that vibration isolation along spatial three-movement two-rotation directions can be realized. Each vibration isolation subsystem in each branched chain is formed by connecting a linear spring (3) and a magneto-rheological damper (4) in parallel; and control over the entire platform is realized by changing a damping coefficient of the magneto-rheological damper. Since the movement and the rotation of a hybrid mechanism are fully decoupled, the control of the system is relatively simple. Experiments prove that the vibration isolation platform using the five-dimensional vibration isolation device enables that a vibration signal transferred to the equipment by the carrier is obviously weakened, so that the vibration isolation platform has the advantage of effectively and reliably improving the dynamic environment of the equipment of the dynamic carrier.

The invention discloses a flexible ankle joint device for exoskeletons. The flexible ankle joint device has three degrees of freedom in all, namely a translation degree of freedom and two rotation degrees of freedom, and comprises a foot sole supporting part, foot side supporting parts, a foot heel damper and a leg supporting frame, wherein the foot side supporting parts serve as flexible rotation pairs and play a role in rotating, damping and protecting; the foot heel damper with a magneto-rheological damper plays a role in supporting, damping and protecting a foot heel. According to the flexible ankle joint device, the movement of an ankle joint of exoskeletons can keep synchronous to that of a user; due to three degrees of freedom of movement, the enhancement of matching performance of the ankle joint device to all kinds of lower limb exoskeletons is facilitated; due to the design of a shockproof packed layer and elastic supporting members of the foot sole supporting part, the design of the flexible rotation pairs of the foot side supporting parts and the design of the foot heel damper, the lightening of walking burden of the user is facilitated, and comfort is improved. The flexible ankle joint device can serve as a loaded walking assisting device, a rehabilitation appliance or an ankle joint device for other lower limb exoskeletons and has the advantages of compact structure, stability and reliability in work, high flexibility, comfort in wearing and the like.

The invention discloses a screw groove magnetic flow changeable damper, which comprises a cylinder, a piston inside the cylinder, a piston rod connected to the piston, an exciting coil mounted on said piston. Wherein, the outer side wall of piston and the inner wall of cylinder have throttle channel between them; the wall of piston has screw groove. The invention has the advantages that: via the micro and concentrated screw grooves, the coulomb force of yield flow can be improved without improving viscous damping force; the via the screw pattern, the peak of damping force can be adjusted; the invention can avoid local accumulation of magnetic flow changeable liquid, to avoid foam; and it can prevent the deposition of magnetic flow changeable flow.

The invention relates to a control algorithm of an automotive magneto-rheological semi-active suspension system and real-time optimal current, and belongs to the technical field of dampers. The control algorithm is characterized by comprising the steps that damping characteristics of a magneto-rheological damper and the semi-active suspension system are simulated according to the currently measured current; the current running road condition of an automobile is identified according to the running speed and the vibration acceleration of an automobile body; a real-time optimal damping ratio of the semi-active suspension system and an optimal Coulomb damping force of the magneto-rheological damper are determined according to the current running road condition, and speed and suspension parameters; and the real-time optimal control current of the automotive magneto-rheological semi-active suspension under the current running working condition is calculated according to relations among the Coulomb damping force, a structure parameter, a magneto-rheological liquid characteristic parameter, the turn number of an electromagnetic coil and the current. According to the control algorithm, a design level and the performances of the magneto-rheological semi-active suspension system can be raised and improved; design and testing expenses are lowered; and the running smoothness and the safety of the automobile are improved.

The invention discloses a four-bar linkage artificial limb knee joint based on magneto rheological effect, which comprises a thigh bearing part, a shank supporting part, a four-bar linkage mechanism and a semi-active damping force control assembly, wherein the semi-active damping force control assembly comprises a sensor, a control unit, a current driver and a magneto rheological damper; and the magneto rheological damper is adopted as a main semi-active damping force control assembly, and the four-bar linage mechanism is used as a connecting mechanism. The artificial limb knee joint has continuous damping force, adjustable negative and positive damping, wide adjustment range and rapid response, and can better simulate the bending action of the knee joint under the control of a microprocessor; and the magneto rheological damper and the artificial limb knee joint are integrated, therefore, the four-bar linkage artificial limb knee joint has small occupation space and more compact structure, and an artificial limb which has more attractive appearance than the traditional structure is designed based on the four-bar linkage artificial limb knee joint.

A magneto-rheological ("MR") damper having a gas cup that slidably moves within a damper body tube and isolates an MR fluid from a gas in one end of the damper body tube. The gas cup has a dynamic seal that comprises an MR fluid compatible O-ring located in a narrow O-ring groove disposed in an outer surface of the gas cup. The narrow O-ring groove is sized to reduce entrapment of abrasive magnetic particles in the MR fluid between the O-ring and an inner surface of the damper body tube. The O-ring groove has a free roll room of about less than 12%.

A magneto-rheological damper comprises a cylinder barrel, a left end cap, a piston rod, a piston, a right end cap, a connecting barrel, a winding barrel, a coil, an external guide magnet and a cap nut. The magneto-rheological damper has the advantages that the coil slides on the cylinder barrel in the direction identical with motion direction of the piston rod, so that a magnetic core on the piston and the external guide magnet are always guaranteed to form a closed magnetic loop, flow guiding can be functioned by an axial central hole and a radial hole in the piston, and magneto-rheological fluid viscosity can be changed by changing the size of the holes during working of the damper, and further, high-viscosity damping force can be generated. The coil is arranged outside the cylinder barrel, convenient for winding, convenient to maintain and check and good in sealing performance. By directly inflating the damper, extra purchasing an energy storage device is omitted, and the magneto-rheological damper has high applicability. Since the magneto-rheological damper is good in damping property, the magneto-rheological damper can be mounted on mechanical structures required to be damped, such as suspension damping of automobiles, damping of undercarriages of planes, damping of seats and bridges.

The invention discloses an impact test bed of magneto-rheological damper and an impact test device. The impact test bed comprises a test bed which comprises two bases and a plurality of guide rails horizontally arranged on the two bases, a mass block arranged on the guide rail in a sliding way, an impact generating device which is arranged at one end of the guide rail and fits the mass block, a buffer which is arranged at the other end of the guide rail and corresponds to the mass block, the magneto-rheological damper connected with the mass block, a sensor arranged on the mass block or the magneto-rheological damper or the test bed respectively, an impact signal processor electrically connected with the sensor, and a current controller electrically connected with the sensor and the magneto-rheological damper respectively, wherein the impact signal processor acquires and processes a signal from the sensor and outputs a voltage signal to the current controller; and the current controller controls the magnitude of a damping force produced by the magneto-rheological damper by adjusting output current according to the voltage signal. The impact test bed and the impact test device can be used for testing the dynamic characteristics of the magneto-rheological damper under the action of an impact load, and verifying the effectiveness of a control method.

The present invention discloses a modeling method for a magneto-rheological damper inverse model and application thereof. The modeling method is characterized by deriving a mathematical expression of the magneto-rheological damper inverse model on the basis of a transformation model of a Bouc-Wen model, and establishing a correspondence relationship among an excitation current of a magneto-rheological damper, a controllable damping force, a relative offset of the damper and a relative speed of the damper. A control circuit of the magneto-rheological damper inverse model comprises an implementation circuit of the magneto-rheological damper inverse model, a magneto-rheological damper driving circuit and the magneto-rheological damper, which cooperatively constitute a closed-loop control system of the magneto-rheological damper. According to the modeling method for the magneto-rheological damper inverse model and the application thereof, which are disclosed by the present invention, the modeling process of the magneto-rheological damper inverse model can be simplified, and an error of the damping force of the magneto-rheological damper, which is caused by an inherent non-linear hysteresis characteristic, is reduced, so that control precision of the damping force is improved.

Aiming at the hysteresis nonlinearity of a magneto-rheological damper (MRD) and the change of a vehicle load, the invention discloses a control method aiming at a mixed semi-active variable structure of a ''1/4'' magneto-rheological intelligent vehicle suspension, wherein an improved ceiling suspension system is used as a reference model, the asymptotically stable sliding mode control is realizeddynamically according to the error between the controlled system and the reference model, and an MRD inverse model and a symmetrical damping type MRD are used for generating two basic control policies of asymmetrical damping characteristics to realize real-time tracking control of the MRD damping force to the ideal damping force thereof, thereby improving the comprehensive performance of the ''1/4'' MR vehicle suspension system, enhancing the robustness to the change of the vehicle load, and effectively inhibiting the adverse effect on the system performance by the hysteresis nonlinearity of the MRD.

The invention discloses a magneto-rheological damper for a suspended mass pendulum, and belongs to the field of vibration control of civil engineering. The magneto-rheological damper for the suspended mass pendulum is a suspended-mass-pendulum damper capable of being controlled in a semi-active mode. The magneto-rheological damper comprises a magneto-rheological pendulum shaft system, a rigid suspender, a balancing weight and the like. A closed magneto-rheological device is designed in a rotary bearing of the suspender to close a rotary shaft in a magneto-rheological fluid environment; blades are arranged on the bearing and control the state of magneto-rheological fluid through a control power source so as to achieve the objective of adjustable blade resistance. The magneto-rheological damper is applicable to flexible structures and high-rise structures of civil engineering structures, and breaks through the limitation of uncontrollable pendulum angles and speeds of pendulum shafts of conventional mass pendulum systems. The civil engineering structures are large in size, tuned mass pendulum dampers applied to the civil engineering structures are large in mass, and thus high power is needed for realization of semi-active control of mass pendulum devices. A magneto-rheological system is low in power consumption and high in force output, so that semi-drive control on the tuned mass pendulum dampers can be realized only by a small amount of currents.

The invention relates to a space robot structure, in particular to a soft contact joint based on motion and static blocks. The soft contact joint comprises a driving and transmission mechanism, a damping component and a sensing unit, wherein the driving and transmission mechanism mainly comprises a motor driving unit, a controller, an inner shell, an outer shell, a sliding block and a sliding rail, the damping component mainly comprises a linear magneto-rheological damper, a clutch, a rotary magneto-rheological damper, a spring mechanism and a torsion spring mechanism, and the sensing unit comprises an encoder and a linear displacement sensor. The overall flexibility of the mechanical arm joint is mainly controlled by the clutch and the magneto-rheological dampers in the damping component, pitching and yaw two-degree-of-freedom rigid driving and spatial six-dimensional momentum discharge interconversion can be achieved according to an operation task, and then soft contact of spatial operation is achieved.

The invention discloses a magneto-rheological pipeline dual-dynamic damping absorber. The mode of combining dynamic vibration absorption and damping dissipation energy vibration damping is adopted for controlling vibration of a pipeline. A magneto-rheological damper is adopted as a mass block and a leaf spring to form a first-order dynamic vibration damping structure, when the pipeline vibrates, the mass block and the leaf spring vibrate along with the pipeline and generate inertia reactive force, and vibration of the pipeline is lowered. A piston body, a spring, magneto-rheological fluid and a cylinder tube of the magneto-rheological damper form a second-order dynamic damping vibration damping structure. When the magneto-rheological damper vibrates along with the pipeline, the piston body compresses the piston to generate reactive force for the magneto-rheological damper under the inertia effect, and when the piston body and the cylinder tube move relatively, the piston body dissipates vibration energy under the damping force effect of the magneto-rheological fluid. The controller adjusts the damping force according to the vibration acceleration of the pipeline, and the energy dissipation efficiency of the damper is improved. One way, radial, axial and fixing frames can be flexibly assembled according to the pipeline vibration phenomenon, and vibration of the pipeline in any direction is controlled.

The invention discloses a rotary type magneto-rheological damper which is characterized in that the damper mainly comprises an outer shell, a front end cap, a back end cap, a front magnet exciting coil, a back magnet exciting coil, a rotor, a bearing, a sealing washer, seal rings and magnetic isolation rings. The front and back end caps are located at the two sides of the rotor and are respectively connected with the outer shell, forming a stator. The bearing and the sealing washer are respectively arranged between the rotor and the front and back end caps. The front and back magnet exciting coils are wound inside the front and back end caps. The magnetic isolation rings are respectively installed between the front and back end caps and the outer shell, and O-shaped seal rings are respectively arranged between the magnetic isolation rings and the outer shell as well as the front and back end caps. A sealed liquid charging hole is formed at the upper part of the outer shell, and magneto-rheological fluid is filled in a hollow cavity between the stator and the rotor. The front and back magnet exciting coils are wound in the same direction, with the tail ends being connected with each other in series and the head ends being loaded with power sources. The two magnet exciting coils form two parallel magnetic pathways which generate two magnetic fields in opposite direction, and the magnetic flux is generated by a single piece of magnet exciting coils.

The invention relates to a semi-active variable-rigidity variable-damping mixed damper. The semi-active variable-rigidity variable-damping mixed damper mainly comprises U-shaped hydraulic cylinders, a transmission device, a magneto-rheological damper and the like. A proper amount of liquid is injected into the U-shaped hydraulic cylinders, pistons are placed on the U-shaped hydraulic cylinders and composed of upper piston bodies and lower piston bodies, springs are clamped between the upper piston bodies and the lower piston bodies, and the pistons are connected with the magneto-rheological damper through the transmission device. The magneto-rheological damper can generate damping force of different magnitudes by changing the magnitude of applied current, and therefore a horizontal sliding rod is controlled to move. When the magneto-rheological damper does not generate the damping force, the pistons at the two ends in the U-shaped hydraulic cylinders can freely move, and earthquake energy is consumed completely through free vibration of the liquid in the cylinders. When the magneto-rheological damper generated the damping force, due to the incompressibility of the liquid, the springs begin to be compressed, and rigidity is provided for a controlled system accordingly, In addition, the earthquake energy is dissipated through the damping force generated by the magneto-rheological damper in a friction energy consumption mode, and therefore the dual effects of adjusting the rigidity and damping of the controlled system in a semi-active mode are achieved.

The invention relates to a magneto-rheological hydraulic rubber air spring, which comprises an upper fixed sealing plate, a lower fixed sealing plate and a rubber outer bag. Magneto-rheological liquid is filled in the rubber outer bag, a rubber bag is arranged in the rubber outer bag, the rubber bag is connected with the upper and lower fixed sealing plates, and the magneto-rheological liquid is connected with a magneto-rheological hydraulic adjusting system. The air spring solves the problem of automatically adjusting the height and the rigidity in real time, has the characteristics of high oil resistance, wide adjustment range, strong temperature adaptability, high response speed, simple structure, small volume and low cost, and can be used for an automobile active suspension system; and if the air spring is integrated with a magneto-rheological damper, the automobile active suspension system with real-time automatic variable height, variable rigidity and variable damping can be formed; and the air spring also can be applied to other vibrating active control systems.

The invention discloses a cushioning and vibration damping device for a support of an intelligent well. A magneto-rheological damper comprises a cylinder tube, wherein the top of the cylinder tube is connected into a whole with a column cap, a floating piston is arranged inside the cylinder tube, a spring is fixed between the floating piston and the column cap, a piston is arranged in the space of the lower part of the floating piston inside the cylinder tube, and filled with magneto-rheological fluid, a channel is formed inside the piston, a coil is wound on the outer side of the piston, a piston rod is connected below the piston, penetrates the bottom of the cylinder tube and is fixed on a column body, a disc spring set is installed on the outer surface of the cylinder tube through an inner hole of the disc spring set, the upper end of the disc spring set is connected with the column cap, the lower end of the disc spring set is connected with the column body, a pressure sensor is installed on a support of the column cap and the disc spring set and also connected with a controller, and the controller is used for controlling the carrying current of the coil. The cushioning and vibration damping effects of the support of the well to rock pressure impact are optimized through realizing the real-time control.

The invention discloses a single-output rod double-cylinder magneto-rheological damper which comprises a working cylinder, a piston, a piston rod, a compensating cylinder, a damping tube and an electric magnet. The piston is mounted in the working cylinder; the piston rod is fixed at one end of the piston; the piston rod is extended out from the working cylinder through a sealing structure at one end of the working cylinder and a bearing; the other end of the working cylinder is communicated with one end of the damping tube; the other end of the damping tube is communicated with the compensating cylinder; a compensating piston is mounted in the compensating cylinder; a compensating spring or a compensating gasbag is mounted below a floating piston; the compensating spring or the compensating gasbag is fixed at the bottom of the compensating cylinder; and magneto-rheological fluid is filled in the working cylinder and the damping tube. The single-output rod double-cylinder magneto-rheological damper is an extrusion flow magneto-rheological damper with simple structure.

The invention discloses a magneto-rheological damper which has high output, wherein a master cylinder barrel is connected with an upper and a lower end covers of the master cylinder, a piston rod of the master cylinder is inserted in the steel cylinder of the master cylinder through a sealing ring which is arranged on the end cover of the main cylinder, the invention also comprises an auxiliary cylinder inner barrel which is communicated with the master cylinder barrel through an upper and a lower channels, an auxiliary cylinder outer barrel which is sleeved on the auxiliary cylinder inner barrel, a plurality of auxiliary cylinder piston slabs and permanent-magnet slabs which are alternately sleeved on an auxiliary cylinder piston rod, the auxiliary cylinder piston rod is inserted in the auxiliary cylinder inner barrel through an auxiliary cylinder end cover, and a groove is opened on the auxiliary cylinder inner barrel and an excitation coil is winded on the groove. The damper greatly improves the proportion of the effective length under the condition that the whole length of the damping channel is determined, basically realizes that the full damping channel is effective, which are larger one time than the traditional shearing valve type magneto-rheological damper with the same size, and simultaneously the damper has great anti-settlement performance and fail-safe performance.

The invention relates to a self-energized damping-adjustable shock-absorbing device, which belongs to the technical field of energy conservation and emission reduction for automobiles. The self-energized damping-adjustable shock-absorbing device comprises a linear motor, a magneto-rheological damper, a bridge type rectifier, a DC-DC convertor and an accumulator, wherein the linear motor and the magneto-rheological damper are connected integrally and coaxially; one end of the bridge type rectifier 19 is connected with the linear motor, and the other end of the bridge type rectifier 19 is connected with one end of the DC-DC convertor; the other end of the DC-DC convertor is connected with the accumulator 25, so that energy is recovered; and the output end of the accumulator 25 is electrically connected with a magnet exciting coil 8 and transmits the stored electric energy to the magnet exciting coil 8. The stored electric energy is used for adjusting the current of the magnet exciting coil 8, so that the damping of the magneto-rheological damper 15 can be adjusted; and at the same time, the damping force of the linear motor is adjusted by adjusting the voltage output to a suspension according to different modes of the DC-DC convertor, so that a state of self-energization and dual damping effect is realized.

The invention discloses a magneto-rheological damping control method based on an improved leapfrogging algorithm. A fuzzy controller based on the magneto-rheological damping control method is used to establish a relation between a structural seismic response and input voltage of a magneto-rheological damper, wherein the structural seismic response is input of the fuzzy controller, and the input voltage of the magneto-rheological damper is output of the fuzzy controller. For solving the problem that difficulty is brought to design of the fuzzy controller due to the fact that parameter selection of the fuzzy controller depends on expert advice, the magneto-rheological damping control method uses the improved leapfrogging algorithm to adaptively optimize various parameters of the fuzzy controller, which comprise parameters of a membership function, fuzzy rules and input quantification factors, and therefore guarantees that the fuzzy controller after being optimized can provide superior voltage value for the magneto-rheological damper, and then enables the magneto-rheological damper to provide optimal damping force for constructions in an earthquake. The magneto-rheological damping control method based on the improved leapfrogging algorithm not only can improve effectiveness and stability of a control system, but also can guarantee shock absorption effects.