58results about How to "Improve low frequency vibration isolation performance" patented technology

The invention discloses a load-bearing adjustable zero-stiffness electromagnetic vibration isolator and a control method thereof. An electromagnetic spring of the vibration isolator in the perpendicular direction is composed of three permanent magnets and two groups of controllable direct current electromagnets, two magnets have opposite polarity and generate repulsive force, and stiffness of theelectromagnetic spring can be adjusted by changing and controlling current. An electromagnetic spring of the vibration isolator in the horizontal direction is composed of two groups of symmetrically distributed electromagnetic springs, and stiffness of the electromagnetic spring can be adjusted by changing and controlling current. When the system load-bearing weight is changed, the stiffness of the perpendicular electromagnetic spring and the stiffness of the horizontal electromagnetic spring are led to meet a certain proportional relationship by adjusting and controlling current so that stiffness of the system at the balance position can be zero. When a vibration isolation device is in small vibration near the balance position, dynamic stiffness is very small, and natural frequency of the whole system is very low so that the vibration isolator can achieve wide-range frequency vibration isolation and has good low frequency vibration isolation effect. In addition, the vibration isolator is compact in structure, light in weight and convenient to control.

The invention discloses a differential magnetic suspension vibration isolator which comprises an upper annular E-shaped electromagnet (15), a lower annular E-shaped electromagnet (11), an upper coil winding (8), a lower coil winding (10), a displacement sensor (1), a connecting flange plate (3), an adjusting nut (4), a spring (6), a linear bearing (7) and an armature (9). The upper annular E-shaped electromagnet (15) and the lower annular E-shaped electromagnet (11) are fixed onto a shell (14) and a base (12) respectively, the upper coil winding (8) and the lower coil winding (10) are fixed onto the upper annular E-shaped electromagnet (15) and the lower annular E-shaped electromagnet (11) respectively, the displacement sensor (1) is fixed onto the shell (14) through a support (16), the connecting flange plate (3), the adjusting nut (4), the spring (6), the linear bearing (7) and the armature (9) are sequentially connected in series from top to bottom through connecting rods (5), the shell (14) is fixed onto the base (12), and a sleeve (13) is fixed into the shell and matched with a spiral groove in the inner wall of the shell to form a sealed cooling water channel. The differential magnetic suspension vibration isolator has the advantages of simple structure, small size, non-contact, long service life, rapid response and easiness in regulating electromagnetic force, and has an excellent application prospect in the field of active vibration noise control.

The invention discloses a quasi-zero stiffness positive stiffness adjusting method, a quasi-zero stiffness adjusting method and a vibration isolator, wherein the positive stiffness adjusting method includes the following steps: arranging a movable supporting column in the quasi-zero vibration isolator; connecting a body by vibration isolation to the top of the supporting column; sequentially arranging a magnet I and a magnet II along the axial direction of the supporting column; arranging the magnet I at the bottom of the supporting column; arranging the magnet II on the quasi-zero vibration isolator, wherein the magnet I and the magnet II are arranged in opposite magnetic poles; arranging a plurality of magnets III on the quasi-zero vibration isolator positioned between the magnet I and the magnet II along the circumferential direction of the supporting column, wherein the magnets III are arranged in opposite magnetic poles, and the same-sex magnetic poles arranged among the magnets III and the same-sex magnetic poles arranged between the magnet I and the magnet II belong to the same polarity. When the quasi-zero stiffness and positive stiffness is adjusted, the magnetic line density between the magnet I and the magnet II is adjusted by changing the magnetic line state among the magnets III, so that the adjustment of the quasi-zero stiffness and positive stiffness can be realized.

The invention belongs to the field of technologies related with ultra-precision active vibration isolation, and discloses an active vibration isolation controller and a design method thereof. The design method comprises the following steps: (1) designing a feedback controller based on an equivalent model after acoustic emission sensor is extended to determine a bandwidth extension frequency pointof a feedback control error sensor; (2) designing the feedforward controller, and determining a bandwidth extension frequency point of a feedforward reference sensor according to a noise constraint condition, noise performance constraint condition being that the rVPSD of a load caused by noise in a feedback strategy is smaller than or equal to 0.707 times of the rVPSD of the load without the feedback strategy, and the noise constraint condition being that the noise equivalence speed of the feedforward reference sensor noise is smaller than or equal to 0.707 times of the rVPSD of foundation vibration. As low-frequency extension of the sensor and an active vibration isolation controller are unified, the stability is improved, and the control loss caused by insufficient or excessive bandwidthextension of the sensor is avoided.

The invention provides a high-linearity quasi-zero stiffness vibration isolator which comprises a supporting plate, an upper frame, a lower frame, eight sets of horizontal spring mechanisms, eight sets of connecting rod mechanisms, a three-permanent-magnet mechanism, four sets of vertical supporting mechanisms and a base. Mounting holes are machined in the supporting plate. Four of the eight sets of horizontal spring mechanisms are installed on the upper frame and connected with the supporting plate through bolts. The other four of the eight sets of horizontal spring mechanisms are installed on the lower frame and connected with the base through the four sets of vertical supporting mechanisms. The upper frame and the lower frame are connected through bolts. The connecting rod mechanisms are installed between the eight sets of horizontal spring mechanisms and the three-permanent-magnet mechanism and connected in a hinged mode. A groove is designed to be formed in the middle of the joint between the upper frame and the lower frame and used for fixing a middle permanent magnet of the three-permanent-magnet mechanism. According to the high-linearity quasi-zero stiffness vibration isolator, main nonlinear stiffness terms are counteracted, high linearity of the quasi-zero stiffness vibration isolator is guaranteed, dynamic behaviors of quasi-zero stiffness are more stable through the achievement of high linearity, the vibration isolation performance is more excellent, and the high-linearity quasi-zero stiffness vibration isolator can be better used for vibration control.

The invention discloses an active control type hydraulic mount of an automobile power assembly. An upper liquid chamber is formed by a mount shell and a driven disk, and a rubber check ring is respectively in vulcanization connection with the mount shell and the driven disk, so that the upper liquid chamber is sealed; a lower liquid chamber is formed by the driven disk, a base membrane and an actuating ejection rod, and a sealing ring is installed in the base membrane and makes contact with the actuating ejection rod, so as to prevent liquid leakage; an actuator is in threaded connection with the actuating ejection rod, and the actuating ejection rod is connected with the driven disk; an inertial channel is formed in the driven disk, so that the upper liquid chamber communicates with the lower liquid chamber. The active control type hydraulic mount is improved on the basis of an original hydraulic mount, the structure is simple, and partial components and parts are versatile. Active control is realized by utilizing the actuator and can adapt to the action of wide-frequency excitation force generated by a power assembly system, the transferring of vibration of the power assembly to an automobile frame is obviously reduced, and the vibration and noise which are generated by the power assembly system are effectively isolated. The active control type hydraulic mount has the characteristics of low cost, simplicity in manufacturing, good reliability and the like.

The invention discloses an electromagnetic type active and passive integrated vibration isolator. In the structure of the electromagnetic type active and passive integrated vibration isolator, an electromagnetic actuator consists of an actuator stator and an actuator rotor; the actuator rotor is installed inside the actuator stator and is coaxial to the actuator stator; the actuator stator consists of a coil, a stator frame, a stator lower end cover and a stator upper end cover; the coil, the stator frame, the stator lower end cover and the stator upper end cover are adhered to form an overall body by using AB glue; the actuator rotor consists of a permanent magnet and a rotor yoke; the permanent magnet is adhered with the rotor yoke to form one overall body by using the AB glue; a passive vibration isolator and the stator frame of the electromagnetic actuator are fixedly arranged on an actuator pedestal; the rotor yoke and the passive vibration isolator are fixed together, and the passive vibration isolator is positioned inside the rotor yoke; an equipment connecting part and a safety shielding cover are fixed to the rotor yoke; and the equipment connecting part is higher than the safety shielding cover. The electromagnetic type active and passive integrated vibration isolator disclosed by the invention belongs to active and passive combined vibration isolation and has the advantages of low energy consumption, high space utilization rate, high reliability, high adaptability, wide vibration absorption frequency band and the like.

The invention relates to a low-frequency, vibration isolation and shakeproof skid bed for vibration isolation, shakeproof, buffering, impact resistance and structural noise reduction in shipping, vehicle, building, bridge, engineering machinery and various electromechanical appliances and engineering facilities. The invention is characterized in that a spiral elastomer made of a plurality of stainless steel twisted wires in a symmetrical or antisymmetric structure mode, a multidirectional elastic position-limit mechanism, a metal structural member, an angle switching rack and a mounting base are connected into a whole by screw threads, which has the properties of multidirectional nonlinear softened rigidity and dry damping and the function of displacement limitation. The low-frequency, vibration isolation and shakeproof skid bed is suitable for the control of large energy input (such as earthquakes, explosion impact, ocean wave, large low-frequency displacement interference, etc) in any direction, meets the needs of multidirectional low-frequency vibration isolation, buffering, shakeproof and large displacement dynamic stability in engineering and has a safe and reliable structure, long life-span, strong adaptive capacity to environment and low maintenance cost.

A two-layer plate frame type vibration damping base of a composite structure comprises an equipment installation rigid base, an upper layer composite material plate frame, a middle layer rigid vibration-isolation panel, a lower layer composite material plate frame and a rigid connection transition plate which are sequentially distributed from top to bottom in the vertical direction. The upper end and the lower end of the upper layer composite material plate frame are fixedly connected with the equipment installation rigid base and the middle layer rigid vibration-isolation panel respectively, and the upper end and the lower end of the lower layer composite material plate frame are fixedly connected with the middle layer rigid vibration-isolation panel and the rigid connection transition plate respectively. By means of the two layers of composite material plate frames, a hard-soft-hard-soft-hard elastic vibration-isolation structure is integrally formed, characteristics of a composite material can be fully used, the dual aims of reducing vibration and noise and reducing the weight of the base are achieved on the premise that the rigidity and strength requirements of the vibration damping base structure are met, and low-frequency noise reduction can be achieved.

The invention provides a ship high transmission loss base structure. The base structure comprises a base structure main body which is prepared by connecting a base face plate, a base web plate and a base wrist plate together and a connection mechanism which is prepared by connecting a transverse installation grillage, a vertical installation grillage and a support wrist plate; the base face plate has a section of an expansion base face plate extending out of the base web plate, the expansion base face plate is provided with a vibration-absorbing covering layer; the base web plate and the vertical installation grillage are arranged in staggering manner, namely the base web plate retracts the installation grillage for a certain distance; and the base web plate is provided with a vibration isolation mass. The invention ensures that the ship base structure transmits the interactive load between the ship hull and the device, has a good effect of isolating the vibration wave transmitted by the device so as to prevent the transmission, has good economy and wide application prospect and is applicable to typical high transmission loss base structures of various ships.

The invention belongs to the technical field of vibration and noise control and particularly relates to a high-performance low-frequency vibration isolation technology having stronger applicability. For solving the problem of low-frequency vibration isolation of mechanical devices, the invention provides a low-frequency vibration isolation system. The low-frequency vibration isolation system comprises a quasi-zero stiffness module, a vibration signal monitoring module, a control module and an execution module. Firstly, passive isolation of low-frequency vibration is achieved by utilizing the quasi-zero stiffness vibration isolation module, whether a control signal is output to the execution module through the control module or not is judged according to the motion state of the quasi-zero stiffness vibration isolation module, and accordingly the system has the advantage of always working on an attractor having the best whole vibration isolation effect. The system is good in operabilityand simple in identification and suitable for engineering practice application and provides an efficient and reliable new thought for low-frequency vibration control, required input energy is smaller,and the executed control times are fewer.

The invention relates to a quasi-zero stiffness vibration isolation system with a bending moment resistance effect. The quasi-zero stiffness vibration isolation system comprises a base, a support cylinder, a vertical elastic element, a vertical damper and at least four groups of lateral support assemblies, and the vertical elastic element, the vertical damper and the lateral support assemblies arevertically arranged; each group of lateral support assembly comprises at least one horizontal damping device; each horizontal damping device comprises a horizontal damper and a lateral elastic element; each horizontal damper is arranged in the horizontal direct; one end of each lateral elastic element is connected with a cylinder body of the horizontal damper, and the other end of each lateral elastic element is connected with the output end of the horizontal damper; and one end of each horizontal damper is hinged with the base, and the other end of each horizontal damper is hinged with the support cylinder. According to the quasi-zero stiffness vibration isolation system with the bending moment resistance function, a multilayer layout mode with lateral support is adopted and the verticaldamper and the horizontal dampers with variable damping are arranged, so that the quasi-zero stiffness vibration isolation system with the bending moment resistance function, which is close to the vibration isolation in the full frequency band range and has the bending moment resistance and lateral impact load functions is realized, the load is large, and the low-frequency vibration isolation effect is good.

The invention relates to an extremely-low-frequency air bag vibration isolation system. The extremely-low-frequency air bag vibration isolation system mainly comprises a vertical air bag vibration isolator, a lateral air bag vibration isolator, a rotating structure, a connecting structure and a loading platform; the vertical air bag vibration isolator is used for bearing loads and achieving vertical vibration isolation; the lateral air bag vibration isolators are used for improving the stability of the system, preventing the loading platform from directly colliding with a lateral foundation under the working conditions of swinging and the like, and meanwhile achieving lateral vibration isolation; the rotating structure and the connecting structure are used for reducing the adverse effect of the lateral air bag vibration isolator on the system and ensuring the system stability under the working conditions of swinging and the like; and meanwhile, on the basis of the structure, the rotation rigidity of the lateral air bag vibration isolator can be reduced through the design of the lateral air bag vibration isolator, negative rigidity is provided for the system, and the vibration isolation performance is further improved. The vibration isolation system is simple in structure, high in reliability and low in cost, and can be used for low-frequency efficient vibration isolation of mechanical equipment and systems for industry and civil use, especially in the field of ships and warships.

The invention relates to a U-type vibration isolating device with a novel composite material structure. The U-type vibration isolating device comprises an equipment installing base, wherein the equipment installing base is fixedly connected with a vibration isolating raft frame of a sandwich composite material; the sandwich composite material is at least composed of two sandwich composite material structural beams arranged at intervals; inside and outside of every sandwich composite material structural beam and the end part of the sandwich composite material structural beam are connected with a hull steel substrate through a vibration isolator; three-directional limiting mechanisms are further arranged at the outside and the end part of every sandwich composite material structural beam; the three-directional limiting mechanisms are respectively and fixedly connected with the hull steel substrate and the sandwich composite material structural beams. The U-type vibration isolating device combines the vibration isolating raft frame, the vibration isolator and the three-directional limiting mechanisms; obviously damping effect is generated within a wide frequency band scale, and underwater noise caused by transmitting vibration of a power mechanical device to a hull structure is reduced.

The invention discloses an elevator car floor vibration-damping device and an elevator, the elevator car floor vibration-damping device comprises a plurality of vibration-damping components, and each vibration-damping component includes a lower bearing plate, an upper bearing plate, a plurality of springs connected between the upper bearing and the lower bearing plate, support posts that run through the upper bearing plate and the lower bearing plate and that each have an upper end fixedly connected with the upper bearing plate and a lower end positioned below the lower bearing plate, and rubber blocks sleeving the lower ends of the support posts and pressing between the lower surface of the lower bearing plate and the lower ends of the support posts. By using the elevator car floor vibration-damping device on the elevator, it is possible to provide high static compression capacity, low inherent frequency and good low-frequency vibration-isolating performance for the elevator, and a rider can feel vibration damping being similar to energy-absorbing vibration damping; the elevator car floor vibration-damping device is suitable for vibration isolation for an elevator; in the case that the elevator experiences weightlessness (i.e., the elevator runs downward), for vibration damping when a car rebounds up occasionally due to various impact loads, the rubber blocks are arranged on the lower surface of the lower bearing plate, rubber is under pressure during rebounding, and reliable vibration damping is provided.

The invention provides a multifunctional compound vibration isolator with both stiffness and damping being adjustable, and the multifunctional compound vibration isolator combines a high static stiffness and low dynamic stiffness vibration isolation technology and a variable damping technology. The structure of the multifunctional compound vibration isolator is mainly formed by an electromagneticvibration isolator with the high static stiffness and low dynamic stiffness feature and a magneto-rheological damper through parallel connection. The electromagnetic vibration isolator and the magneto-rheological damper are independently electrified, the multiple functions are achieved, and meanwhile the problem that the vibration damping performance deteriorates due to a jumping phenomenon when an existing negative stiffness technology is applied can be well solved. The electromagnetic vibration isolator adopts a magnetic tooth structure, by changing the input exciting current, online adjustment of electromagnetism stiffness can be achieved, and therefore the inherent frequency of the vibration isolation system is lowered. The variable damping technology adopts the magneto-rheological damper, and the damper of this type achieves damping change also through change of the input current. When the multifunctional compound vibration isolator works, the mode that the electromagnetic vibration isolator works alone, or the mode that the magneto-rheological damper works alone, or the mode that the electromagnetic vibration isolator and the magneto-rheological damper simultaneously work canbe selected.

The invention discloses a seat nonlinear suspension integrating a height and weight parameter adjusting function. The seat nonlinear suspension comprises a shear type suspension assembly and an elastic assembly; the shear type suspension assembly achieves guiding of movement in the vertical direction through a shear rod mechanism and a sliding way roller; the elastic assembly comprises two horizontal springs, an adjusting rod, a weight adjusting plate, two torsion bars which are symmetrically arranged up and down, a main sliding block, an auxiliary sliding block, two rollers which are installed on the two torsion bars respectively, a first torsion bar fixing steel belt, a second torsion bar fixing belt, an inner spline sleeve, a key and a large nut; semi-cylindrical structures are arrangedon the upper face and the lower face of the auxiliary sliding block. According to the invention, the functions of weight adjustment and height adjustment are integrated in the nonlinear seat suspension based on a shear type connecting rod, so that the complexity of an adjusting mechanism is reduced, the number of parts is small, the cost is low, and the suspension has nonlinear characteristics and good low-frequency vibration isolation capability.

The invention relates to a guiding and vibration-isolating coupled seat for a vehicle. The left and right sides of the structure are symmetrical, and one side thereof includes: a seat panel connected in sequence, a scissor mechanism, a shock absorber, a main spring, a seat bottom plate, and a connecting seat. Rod, auxiliary spring cover, auxiliary spring, auxiliary spring base, wherein, the scissor mechanism, connecting rod, auxiliary spring base, auxiliary spring, auxiliary spring cover, seat panel and seat bottom plate together constitute the scissor negative stiffness Vibration isolation mechanism, which has the function of guiding the vertical motion of the seat and the function of negative stiffness vibration isolation. Effective low-frequency vibration isolation is achieved through the joint action of the main spring, shock absorber and scissor-type negative stiffness vibration isolation mechanism. At the same time, the vertical movement of the seat is more stable; Seats are fairly vibration-isolating. The seat of the invention is simple and compact in structure, uses few parts, is easy to install, has stable performance, low cost, good vibration isolation effect and reliability, and is suitable for vehicles such as trucks, armored vehicles, rail vehicles and engineering vehicles.

The invention aims at providing a permanent electromagnetic compounding semi-active vibration isolation actuator. A permanent magnet is arranged between a first shell and a second shell. A hollow shell structure is jointly formed by the first shell, the permanent magnet and the second shell. A spindle is mounted in an armature, the armature is mounted in the shell structure, and the first end of the armature stretches out of the second shell. A flange and the end of the second shell are fixed. A first bearing end cover is fixed to the end of the first shell. A second bearing end cover is fixed to the end of the flange. The first bearing end cover and the second bearing end cover are arranged outside the two ends of the spindle correspondingly. The outer sides of the two ends of the spindle are each provided with a nut. Springs are mounted between one nut and the first bearing end cover and between the other nut and the second bearing end cover correspondingly. The permanent electromagnetic compounding semi-active vibration isolation actuator combines the functions of a passive vibration isolator and a controllable rigidity actuator in a traditional semi-active vibration isolation system, and meanwhile the problem that the passive vibration isolator in the traditional semi-active vibration isolation system is instable is solved.

The invention provides a composite damping structure for an airborne photoelectric system. The composite damping structure comprises a round upper end cover, a round lower end cover connected with anairborne platform, a round bearing disc connected with the photoelectric system, eight steel wire rope dampers evenly distributed on the periphery, eight rubber dampers evenly distributed on the periphery and a cable connected with the photoelectric system and an upper computer. The upper end cover and the lower end cover are connected through bolts to form a cylindrical sealed inner cavity. The bearing disc is installed in the middle of the inner cavity, and the inner cavity is divided into an upper cavity and a lower cavity. The eight steel wire rope dampers and the eight rubber dampers areevenly distributed in the circumferential direction of the bearing disc in the lower cavity. The cable is arranged and connected into the upper cavity. According to the composite damping structure, the damping structure is externally moved from the interior of the photoelectric system to the position between the photoelectric system and the airborne platform, integrated and compact structure design is used in the aspect of design of the damping structure, the damping structure is designed as a half-closed device which can be replaced wholly, interior components of the damping structure are completely separated from the exterior harsh environment, and the high outer field maintenance and reliability are ensured.

The invention discloses a nonlinear stiffness vibration-isolation platform for optoelectronic equipment, and relates to the technical field of vibration-isolation buffering of the photovoltaic equipment. The vibration-isolation platform is composed of an upper panel, a lower panel, a nonlinear stiffness assembly, an auxiliary stiffness assembly and a vertical guiding assembly; the upper surface ofthe upper panel is fixedly connected with the photovoltaic equipment subjected to vibration isolation, and the lower surface of the lower panel is fixedly connected with a moving carrying platform; the nonlinear stiffness assembly serves as a main force bearing part of the vibration-isolation platform to convert vertical motion into horizontal motion and provide linear restoring force; the auxiliary stiffness assembly achieves the effect of auxiliary support on the load and is used for increasing the bearing capability of the vibration-isolation platform; and the vertical guiding assembly isused for constraining motion loaded by the upper panel and the vibration-isolation platform. Thus the nonlinear stiffness vibration-isolation platform has very low dynamic stiffness while having the large bearing capability, accordingly, the inherent frequency of a system can be decreased significantly, and the very good low-frequency vibration-isolation effect is achieved; and the nonlinear stiffness vibration-isolation platform is suitable for vibration-isolation buffering application of the large-scale photoelectric equipment.

The invention discloses a double-rigidity damping vibration isolator, a floating slab with the double-rigidity damping vibration isolator and a floating slab track system. The double-rigidity damping vibration isolator comprises a fixing part, and the fixing part comprises a base, a damping cylinder and a sleeve; the damping cylinder is fixed in the middle of the base; the sleeve is correspondingly positioned outside the damping cylinder and is fixed along the peripheral side of the base; a moving part comprises a top cover, a first-stage steel spring, a second-stage steel spring and a damping piston; the top cover is positioned above the sleeve and is movably connected with the upper end of the sleeve through a sealing piece in a sealing manner; the first-stage steel spring is sleeved between the damping cylinder and the sleeve, and the upper end and the lower end of the first-stage steel spring abut against the end faces of the top cover and the base respectively. The second-stage steel spring is arranged in the first-stage steel spring in a penetrating mode, one end of the second-stage steel spring abuts against the step end face of the step-shaped damping cylinder, and a distance is formed between the other end of the second-stage steel spring and the top cover; one end of the damping piston is fixed with the top cover, and the other end is positioned in the smaller-diameter section of the damping cylinder; and the damping cylinder and the sleeve are filled with damping liquid. The structure is simple, and environmental noise can be reduced.

The invention discloses a local resonance type vibration isolation system for low-frequency vibration reduction of a precise instrument. The local resonance type vibration isolation system comprises asimply supported beam and the precise instrument mounted on the simply supported beam, and the precise instrument is mounted on the upper surface of the simply supported beam in a vibration isolationmanner; M local resonance cells are further periodically arranged on the upper surface of the simply supported beam in the axial direction, and each local resonance cell comprises N vibration absorbers; and M*N vibration absorbers are arranged at equal intervals, and the precise instrument is arranged between any two adjacent vibration absorbers. According to the local resonance type vibration isolation system, low-frequency vibration of the precise instrument can be effectively restrained, the local resonance type vibration isolation system is composed of local resonance cells arranged on the beam and the precise instrument, the local resonance cells comprise a plurality of different vibration absorbers, and therefore the effective vibration reduction range and the vibration reduction efficiency of the vibration absorbers can be greatly improved, and an excellent low-frequency vibration isolation effect is achieved; and the system is simple in structure and convenient to machine, install and maintain in the later period, and the application cost is reduced.