A negative stiffness generating mechanism and a quasi-zero stiffness vibration isolator are provided. A housing is mounted on a base, and the axial relative positions of the housing and the base can be adjusted; a negative stiffness unit comprises inner-ring magnets, outer-ring magnets and a supporting shaft, the supporting shaft axially slides on the base and passes through the housing, the inner-ring magnets fixedly sleeve the supporting shaft, and the outer-ring magnets sleeve outside the inner-ring magnets and are divided into upper and lower groups of outer-ring magnets; the upper and lower groups of outer-ring magnets can synchronously move through a negative stiffness adjusting device; and the axial relative positions of the middle planes of the outer-ring and inner-ring magnets can be adjusted by adjusting the axial relative positions of the housing and the base. The isolator comprises a negative stiffness generating mechanism and a positive stiffness unit.

The present disclosure discloses an electromagnetic multistage adjustable variable inertance and variable damping device. Iron cores are magnetized by winding electromagnetic coil windings outside the iron cores and applying an electric current action to the electromagnetic coil windings, and air gap magnetic fields are generated by the magnetized iron cores and permanent magnets in air gaps to cause the variation of shear damping forces between a driving shear plate and magnet yokes and between driven shear plates and magnet yokes, which avoids that the mechanical properties of an inerter cannot be fully utilized due to the friction caused by mutual contact among parts, thereby realizing multistage real-time adjustability of an instance coefficient and a damping coefficient of the device.

The present disclosure discloses an electromagnetic multistage adjustable variable inertance and variable damping device. Iron cores are magnetized by winding electromagnetic coil windings outside the iron cores and applying an electric current action to the electromagnetic coil windings, and air gap magnetic fields are generated by the magnetized iron cores and permanent magnets in air gaps to cause the variation of shear damping forces between a driving shear plate and magnet yokes and between driven shear plates and magnet yokes, which avoids that the mechanical properties of an inerter cannot be fully utilized due to the friction caused by mutual contact among parts, thereby realizing multistage real-time adjustability of an instance coefficient and a damping coefficient of the device.

Various examples of a variable stiffness magnetic spring with a linear stroke length are provided. The stiffness of the magnetic springs is varied through rotation of one or more magnets, and both positive and negative spring constants are achievable. In one example, a variable stiffness magnetic spring includes a first magnetic component and a second magnetic component, wherein the first magnetic component is coaxial with the second magnetic component, the first magnetic component is rotatable about an axis and relative to the second magnetic component to adjust a stiffness of the variable stiffness magnetic spring, and the second magnetic component is translatable along the axis and relative to the first magnetic component. While such variable stiffness magnetic springs exhibit highly linear stroke lengths, such variable stiffness magnetic springs can be positioned in series to achieve an even longer linear stroke length.

Various examples of a variable stiffness magnetic spring with a linear stroke length are provided. The stiffness of the magnetic springs is varied through rotation of one or more magnets, and both positive and negative spring constants are achievable. In one example, a variable stiffness magnetic spring includes a first magnetic component and a second magnetic component, wherein the first magnetic component is coaxial with the second magnetic component, the first magnetic component is rotatable about an axis and relative to the second magnetic component to adjust a stiffness of the variable stiffness magnetic spring, and the second magnetic component is translatable along the axis and relative to the first magnetic component. While such variable stiffness magnetic springs exhibit highly linear stroke lengths, such variable stiffness magnetic springs can be positioned in series to achieve an even longer linear stroke length.

An active vibration controller includes: a housing; a first magnetic member installed on the side of the housing having a toric shape; a movable member including a second magnetic member that is substantially coaxial with the first magnetic member and disposed inside the toric shape of the first magnetic member; an exciting coil that generates a magnetic field in accordance with an intensity of a current supplied thereto; and a magnetic viscoelastic elastomer that has a magnetic viscoelastic property varying in accordance with a magnitude of the magnetic field from the exciting coil between the first and second tip portions, and connects the first magnetic core to the second magnetic core. The magnetic viscoelastic elastomer has a region having a non-magnetic property between the first and the second magnetic cores.

A multi-dimensional magnetic negative-stiffness mechanism and a multi-dimensional magnetic negative-stiffness vibration isolation system composed thereof are provided. The multi-dimensional damping system is composed of a positive-stiffness mechanism, a multi-dimensional negative-stiffness mechanism, a floating frame, a vibration isolated body, and a mounting base. The positive-stiffness mechanism is a traditional elastic element connected to the vibration isolated body and the mounting base, and provides supporting forces in an X direction, a Y direction, and a Z direction, and a basic vibration isolation function. The multi-dimensional negative-stiffness mechanism is composed of at least two negative-stiffness magnetic groups. Each negative-stiffness magnetic group may provide one-dimensional or two-dimensional negative stiffness. Through a series connection of the at least two negative-stiffness magnetic groups, a two-dimensional or three-dimensional negative-stiffness effect may be implemented to improve the vibration isolation performance of the system in multiple dimensions.

An eddy current damper includes a screw shaft, first permanent magnets, second permanent magnets, a cylindrical magnet holding member, a cylindrical conductive member, and a ball nut meshing with a screw shaft. The screw shaft is movable in the axial direction. The first permanent magnets are arrayed along the circumferential direction around the screw shaft. The second permanent magnet is arranged between the first permanent magnets, wherein the arrangement of magnet poles is inverted between the second permanent magnet and the first permanent magnet. The magnet holding member holds the first permanent magnet and the second permanent magnet. The conductive member is opposed to the first permanent magnets and the second permanent magnets with a gap therebetween. The ball nut is disposed inside the magnet holding member and the conductive member, and is fixed to the magnet holding member or the conductive member.

The present disclosure provides a single-degree-of-freedom (SDOF) magnetic damping shock absorber based on an eddy current effect, comprising a lower plate, a ring-shaped magnet a, a ring-shaped magnet b, an aluminum cylinder, a bottom copper sheet, a copper sheet, a top copper sheet, a bearing seat, a linear bearing, a bearing end cap, a load, a piston shaft, a stepped shaft, a fixed collar, a coil spring, a lower clamping shaft, and fixing screws. When the shock absorber is working, the ring-shaped magnet a keeps stationary at the lower end and the ring-shaped magnet b reciprocates in the vertical direction. Both magnets are arranged in a mutual attraction manner. Under the action of a time-varying electromagnetic field generated by the relative movement of the ring-shaped magnet b, the copper sheet arranged between the two ring-shaped magnets generates eddy current damping. The movement of the ring-shaped magnet b is inhibited.

A hydraulic mount assembly includes a mount body defining a cavity. A powertrain includes a dynamic mass, and a structure that supports the dynamic mass. The assembly is attached to the structure and supports the dynamic mass. A first plate is fixed relative to the mount body inside the cavity to separate the cavity into a first chamber and a second chamber. The first plate defines a plurality of first passages that fluidly connects the first and second chambers. A decoupler is disposed between the first and second chambers. An actuator is coupled to the first plate. The decoupler is movable in response to actuation of the actuator. The decoupler abuts the first plate when in a locked position to prevent fluid communication through the first passages. The decoupler is movable relative to the first plate when in an unlocked position to allow fluid communication through the first passages.