A vibration-damping device includes a partition member provided with an orifice passage that allows a main liquid chamber and an auxiliary liquid chamber to communicate with each other, a plurality of first communication holes that allows the main liquid chamber and an accommodation chamber to communicate with each other, and a second communication hole that allows the auxiliary liquid chamber and the accommodation chamber to communicate with each other. A tubular member that protrudes in an axial direction toward the elastic body is disposed on a first wall surface of the partition member to which the first communication holes are open and which constitutes a portion of an inner surface of the main liquid chamber. The plurality of first communication holes are open to both an inner portion located inside the tubular member and an outer portion located outside the tubular member, on the first wall surface.

A partition member includes an orifice passage through which the main liquid chamber and the auxiliary liquid chamber communicate with each other, a plurality of first communication holes through which the main liquid chamber and the accommodation chamber communicate with each other, and a second communication hole through which the auxiliary liquid chamber and the accommodation chamber communicate with each other, in the partition member, a tubular member which protrudes in an axial direction toward an elastic body is disposed on a first wall surface in which the first communication hole opens and which forms a part of an inner surface of the main liquid chamber, the plurality of first communication holes open in both an inner portion located on an inner side than the tubular member and an outer portion located on an outer side than the tubular member of the first wall surface.

Disclosed is a quasi-zero stiffness absolute displacement sensor based on electromagnetic positive stiffness, and relates to the technical field of vibration measurement. The quasi-zero stiffness absolute displacement sensor comprises an eddy current displacement sensor unit, a negative stiffness unit, an intermediate connector, a positive stiffness unit, a bottom shell and a motion axis. The damping of the mechanism can be effectively reduced, the service life of the system is prolonged, and the mechanism size is reduced. By adjusting the number of layers of permanent magnets and coils in the electromagnetic positive stiffness unit and the electromagnetic negative stiffness unit and controlling the magnitude of current in the coils, electromagnetic force between the permanent magnets and the electromagnetic coils can be changed, the magnitude of positive stiffness and the magnitude of negative stiffness are adjusted, and control over the stiffness of the whole system is achieved.

Disclosed is a quasi-zero stiffness absolute displacement sensor based on electromagnetic positive stiffness, and relates to the technical field of vibration measurement. The quasi-zero stiffness absolute displacement sensor comprises an eddy current displacement sensor unit, a negative stiffness unit, an intermediate connector, a positive stiffness unit, a bottom shell and a motion axis. The damping of the mechanism can be effectively reduced, the service life of the system is prolonged, and the mechanism size is reduced. By adjusting the number of layers of permanent magnets and coils in the electromagnetic positive stiffness unit and the electromagnetic negative stiffness unit and controlling the magnitude of current in the coils, electromagnetic force between the permanent magnets and the electromagnetic coils can be changed, the magnitude of positive stiffness and the magnitude of negative stiffness are adjusted, and control over the stiffness of the whole system is achieved.

A first shock isolator is provided that includes an axial compression element, a first disc spring, a disc spring system, and an annular stand-off. The first disc spring has a non-linear load-deflection response. The disc spring system is configured to be deflected by the first disc spring and has a linear load-deflection response. A second shock isolator is provided that includes an axial compression element, first and second disc springs and corresponding first and second annular stand-offs. The first and second disc springs have non-linear load-deflection responses. The first and second annular stand-offs hold the first disc and second disc springs in a spaced apart parallel configuration. The second disc spring is configured to be deflected by the first disc spring. The first and second shock isolators exhibit first and second combined load-deflection curves that include a constant load region.

A gasket includes an elastic part containing a rubber having a dynamic-to-static ratio, Kd/Kst, of 2.5 or lower, wherein the dynamic-to-static ratio, Kd/Kst, is a ratio between a dynamic spring constant, Kd, and a static spring constant, Kst. The dynamic spring constant, Kd, represents a constant as measured under conditions of 23±2° C., 100 Hz, and a strain amplitude of 0.1% according to JIS K6394:2007, and the static spring constant, Kst, represents a constant as measured under conditions of 23±2° C. and a strain amplitude of 0.1% according to JIS K6394:2007.

A gasket includes an elastic part containing a rubber having a dynamic spring constant of 1.5 g/μm or lower as measured under conditions of 23±2° C., 100 Hz, and a strain amplitude of 0.1% according to JIS K6394:2007.

The bushing includes an outer cylinder, an inner cylinder, and an elastic body therebetween. The outer cylinder has a central recess portion formed in a curved shape. The inner cylinder has a central convex portion being formed in a curved shape. A distance between a vertex of the central recess portion and the vertex of the central convex portion is smaller than a distance between a point other than the vertex of the central recess portion and a point at which a straight line extending from the point other than the vertex of the central recess portion to an intersection point of the perpendicular line and the axis of the inner cylinder intersects the central convex portion.

A mounting bushing for a vehicle satisfies durability requirements as well as performance, such as ride comfort, handling, and noise, vibration, and harshness (NVH) reduction. The mounting bushing includes an inner pipe, an elastic portion surrounding an external side of the inner pipe, an intermediate pipe surrounding an external side of the elastic portion and having a cutout provided in an axial direction, and an outer pipe surrounding an external side of the intermediate pipe. The elastic portion is formed of a material having a dynamic ratio lower than a dynamic ratio of a rubber material.

A rotating machine system can include a rotating machine. The rotating machine system can include a housing. The housing can include an inner surface. The housing can surround at least a portion of the rotating machine. The inner surface of the housing can be spaced from the rotating machine such that a space is defined therebetween. The rotating machine system can include one or more super elastic wires. The one or more super elastic wires can be positioned in the space and can be operatively connected to the rotating machine and the inner surface of the housing. The one or more super elastic wires can reduce vibration within the rotating machine system.