An apparatus for damping vibrations includes an inertial mass disposed in a cavity in a rotatable downhole component, the rotatable component configured to be disposed in a borehole in a subsurface formation, such as a resource bearing formation, the inertial mass coupled to a surface of the cavity by a damping fluid and configured to move within the cavity relative to the downhole component. The apparatus also includes a damping fluid disposed in the cavity between the inertial mass and an inner surface of the cavity, where rotational acceleration of the rotatable downhole component causes shear in the damping fluid to dissipate energy from rotational acceleration of the rotatable downhole component and causing the rotational acceleration to be reduced.

A closure package for a vibration damper may include a base body that is connectable to a damper tube and comprises a first end and a second end. The first end forms an end side of the damper tube and the second end is disposed in the damper tube. A seal for sealing a piston rod may be disposed in the base body. A seal holder may be disposed between the seal and the base body at the first end. The seal holder for axially fixing the seal may be connected to the base body in a form-fitting and/or force-fitting manner. The seal holder may be fusible in an emergency. For releasing the connection to the base body, the seal holder may be thermoplastically deformable upon overheating of the vibration damper.

Provided herein is are multilayer damping laminates comprising alternating damping and constraining layers. The materials and configurations of the damping layers are selected such that the damping layers have a decreasing glass transition temperature profile beginning at the first damping layer, allowing the laminates to effectively dissipate vibrations over a wider range of operating temperatures and/or frequencies. Also provided are systems and methods using the multilayer damping laminates.

A locking isolator includes one or more joints. The one or more joints are configured to transition between a clearance fit state and an interference fit state in response to a change in temperature. The locking isolator includes a dampener. The dampener is configured to attenuate transmission of vibration through the one or more joints when the one or more joints are in the clearance fit state.

A spring device for spring-mounting a laundry drum of a washing machine has at least one spring means and coupling means for coupling the spring means to the spring device. The spring means has a spring constant or spring properties which are temperature-dependent and can be varied by a temperature effect on the spring means. As an alternative or in addition, the coupling means are designed in a temperature-dependent manner in such a way that they vary their coupling effect between the spring means and the spring device by a temperature effect. Heating means are provided for the spring means and/or for the coupling means in order to warm up the said spring means and/or coupling means and to change their spring properties or their coupling effect. Therefore, the spring-mounting arrangement of the laundry drum can be thermally, and therefore quickly and simply, varied.

A support assembly for a load-bearing unit, a gas turbine engine including the support assembly, and a method of operation of the support assembly are provided. The support assembly includes a support element, a damper, and a variable stiffness member. The support element supports the load-bearing unit. The damper supports the support element and is configured to provide dampening of the load-bearing unit. The variable stiffness member is positioned between the damper and the load-bearing unit. The variable stiffness member is configured to provide a serial dampening of the load-bearing unit with the damper. The variable stiffness member includes a shape memory alloy.

Provided are a non-aqueous suspension exhibiting an electrorheological effect and a damper constructed using the non-aqueous suspension.

A non-aqueous suspension exhibiting an electrorheological effect, including a non-aqueous liquid; and organic polymer particles dispersed in the non-aqueous liquid, wherein the organic polymer particles have at least one type of ion in the inside or on the surface of the organic polymer particles, wherein when a 5 kV/mm voltage is applied between a pair of electrodes, the logarithmic value of frequency factor in Arrhenius equation for the current density (A/cm.sup.2) flowing between the electrodes through the non-aqueous suspension is 20 or more.

The present invention relates to a device (1) for stabilising joints, comprising a receptacle (20), wherein the receptacle (20) is filled with a filling medium (30), a first body (40) for interaction with the filling medium (30), wherein the first body is arranged displaceably in the receptacle (20), a force-transmission means (50) for the transmission of an external force onto the first body (40), a second body (60) for interaction with the filling medium (30) which is arranged displaceably in the receptacle (20), wherein the second body is coupled elastically to the first body (40) via a coupling element (70), wherein at least one of the second body (60) and the first body (40) have at least one outlet opening (64) through which the filling medium (30) can flow, and wherein the first body (40) forms a valve body and the second body (60) forms a valve seat so that a flow of the filling medium (30) through the outlet opening (64) can be allowed or prevented as a function of the valve position.

Embodiments of the present invention generally relate to a novel system, device, and methods for providing an isolator for components and instrumentation to isolate vibrations, shock, static or quasi-static loads, thermal loads, and electrical currents. The novel isolator has an asymmetrical shape, experiences uniform motion under quasi-static loading, and reduces the effective modal mass across a range of frequencies. The novel isolator outperforms conventional vibration isolators in terms of cost, schedule (manufacturing time and lead time), heat dissipation, and performance.

A computer of an active vibration damping device calculates operation command values for an actuator from rotation information of a drive source, and corrects the operation command values in accordance with an internal temperature of the actuator. The computer applies a drive voltage to the actuator using a voltage duty ratio based on the corrected operation command values. The computer also estimates the internal temperature on the basis of an average duty ratio as an average of the voltage duty ratios in a predetermined interval.