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.

A pulley structure may be equipped with an outer rotating body, an inner rotating body, and a coil spring provided between the outer rotating body and the inner rotating body. The coil spring is configured so as to undergo torsional deformation in a diameter-expanding or a diameter-contracting direction, thereby engaging the outer rotating body and the inner rotating body and transmitting torque, and to undergo torsional deformation in the direction opposite the direction in which torque is transmitted, thereby entering a disengaged state in which the coil spring slides with the outer rotating body or the inner rotating body, thus interrupting the transmission of torque. The number of windings of the coil spring is in a range between [M-0.125] and M (both inclusive), where M is a natural number.

The disclosure relates to a torsional vibration damping assembly comprising a deflection mass carder capable of rotation about a rotational axis and deflection masses mounted following one another in a circumferential direction on the deflection mass carrier and deflectable from a basic relative position, wherein the radial position of the deflection masses with respect to the rotational axis changes on deflection from the basic relative position, with each deflection mass being mounted deflectably in both circumferential directions from the basic relative position by coupling formations on the deflection mass carrier, with a resiliently deformable stop formation being provided and assigned to each deflection mass to haft a deflection movement of the deflection mass once a stop deflection has been reached, with the resiliently deformable stop formation comprising a resilient stop material which is fixedly mounted with respect to the deflection mass carder, with the following ratio R being applicable in the assignment to each deflection mass: R=VE/E wherein VE is an effective stop material volume assigned to a deflection mass on reaching the stop deflection by deformation of the resilient stop material and E is an impact metric relative to the kinetic energy of a deflection mass on reaching the stop deflection, and wherein the following applies for the ratio R: 0.15×10−3 m2/kg≤R≤0.6×10−3 m2/kg.

A hydraulic damper assembly comprises a main tube defining a fluid chamber. An external tube extends about the main tube defining a compensation chamber between the main and external tubes. A main piston, located in the main tube, divides the fluid chamber into a compression chamber and a rebound chamber. A piston rod couples to the main piston. A base valve, located in the compression chamber, couples to the main tube. A hydraulic compression stop, located in the compression chamber, includes an additional piston, an insert, and a fixing member. The additional piston couples to the main piston. The insert, located in the compression chamber, couples to the base valve. The insert has a main section and a terminal section. The terminal section having an external diameter that is less than an external diameter of the main section.

A variable spring rate absorber is adjusted to provide the vibration attenuation characteristics needed to match current operating conditions. Control of a variable spring rate absorber determines the desired absorber spring rate for existing conditions based on a number of inputs and predetermined characterization tables. Once the spring rate is calculated, a predetermined map may be used to determine the absorber setting needed to achieve the desired spring rate. A sensor may be used to measure the actual state of the absorber to determine the extent to which the setting must be adjusted to achieve the desired spring rate.

This disclosure is to provide an anti-vibration device with reduced high frequency vibration. The anti-vibration device (1) according to this disclosure has: elastic bodies (4); and an intermediate plate (5) arranged between the elastic bodies (4) and connected to the elastic bodies (4). The intermediate plate (5) has an acoustic impedance (Z.sub.2) larger than the elastic bodies (4), and a perpendicular line (O) of the intermediate plate (5) is arranged between the elastic bodies (4) in a manner inclined with respect to the vibration input direction at an angle (θ.sub.1).

A damper device includes first inner springs configured to transmit a torque between a drive member and an intermediate member, second inner springs configured to transmit a torque between the intermediate member and a driven member, and a rotary inertia mass damper including a sun gear serving as a mass body rotating with relative rotation of the drive member to the driven member. The rotary inertia mass damper is provided in parallel to a torque transmission path including the intermediate member, the first inner springs and the second inner springs. A damping ratio ζ of the intermediate member determined based on a moment of inertia J.sub.2 of the intermediate member and rigidities k.sub.1 and k.sub.2 of the first and the second inner springs and is less than a value.

A hydraulic damper assembly comprises a main tube defining a fluid chamber. An external tube extends about the main tube defining a compensation chamber between the main and external tubes. A main piston, located in the main tube, divides the fluid chamber into a compression chamber and a rebound chamber. A piston rod couples to the main piston. A base valve, located in the compression chamber, couples to the main tube. A hydraulic compression stop, located in the compression chamber, includes an additional piston, an insert, and a fixing member. The additional piston couples to the main piston. The insert, located in the compression chamber, couples to the base valve. The insert has a main section and a terminal section. The terminal section having an external diameter that is less than an external diameter of the main section.

A damper apparatus includes a first rotating body, a second rotating body, and an elastic mechanism unit including an elastic body and paired seat members. The seat member includes a first surface portion coming into contact with one of the first rotating body and the second rotating body and a second surface portion coming into contact with another of the first rotating body and the second rotating body, a first angle θ1 formed by a first tangent line at a first point of contact, the first tangent line including a first vector and a second vector, and the first vector is 11.5°≤θ1≤22.0°, and a second angle θ2 formed by a second tangent line at a second point of contact, the second tangent line including a third vector and a fourth vector, and the third vector is 11.5°≤θ2≤22.0°.

A bearing bush and a method for producing a bearing bush are provided. The bearing bush includes a core element, an elastomer element, a cage element and a sleeve element. The cage element is at least partially embedded in the elastomer element. The elastomer element elastically connects the cage element and the core element to each other. The core element, the cage element and the elastomer element form a pre-assembly element. One of the sleeve element and the cage element includes a protrusion. The other of the sleeve element and the cage element includes a groove, which is engageable with the protrusion, in an assembled state of the bearing bush. The pre-assembly element is fixed in the sleeve element. The protrusion and the groove form a two-point contact in a cross-section.