An apparatus for damping machining vibrations includes a first dampener having a viscoelastic material, the first dampener to be inserted into an object defining a cavity therein; and a compressor to compress the first dampener in a first dimension to cause the first dampener to expand in a second dimension to engage an interior wall of the object.

A damped propshaft assembly with a hollow shaft and a tuned damper, which is received in the hollow shaft and includes a liner and a damping member. The liner's mass and stiffness are tuned to attenuate one or more of a bending mode vibration and a torsion mode vibration that occurs at a first predetermined frequency. The liner is not configured to substantially damp shell mode vibration that occurs at a frequency that is not equal to the first predetermined frequency. The damping member is coupled to the liner and is configured to primarily attenuate shell mode vibration in the hollow shaft at one or more desired frequencies. The tuned damper attenuates the at least one of the bending moment vibration and the torsion mode vibration at the first predetermined frequency and also attenuates shell mode vibration. A method for forming a damped propshaft assembly is also provided.

A vibration damping device for use with a downhole tool having a tool axis may comprise a device housing mechanically coupled to the downhole tool, wherein the device housing defines a receptacle having a volume and an inner surface; an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis; wherein the inertia element volume is greater than the receptacle volume and an interstitial volume is defined between the inertia element and the receptacle, and wherein the interstitial volume is occupied by a fluid or an elastomer. The device may include a longitudinal bearing and/or a radial bearing between the inertia element and the receptacle. The device may also include a pressure compensation device in fluid communication with the receptacle and positioned within or an integral part of the device housing.

In examples provided herein, a roller damper comprises a damper body element having mass and having a shape to fit an interior of a tubular roller element. The roller element is associated with a natural frequency. The roller damper also comprises an elastomer support member coupled to the damper body element. The mass of the damper body element and the elastomer support member are selected based on the natural frequency of the tubular roller element.

A dynamic damper assembly may include a plurality of bodies arranged at predetermined intervals on an outer peripheral surface of a drive shaft, and an elastic body formed to surround each of the bodies and fixing each body to the drive shaft.

Radial vibration dampers have an inertia member defining an annular channel having (i) a radially facing, open face; (ii) a bottom surface; and (iii) interior, opposing surfaces. The interior, opposing surfaces are each angled outward away from a central transverse plane through the inertia member at an angle in a range from zero degrees to at most 45 degrees. A spring damper member is seated in the annular channel to a selected depth that defines a damper gap between a radial inner surface of the spring damper member and the bottom surface of the annular channel and defines a clearance gap between the shaft and the inertia member. A tuning ratio of the clearance gap to the selected depth is in a range of about 1:1.5 to about 1:0.5.

A vibration absorber for securely fixing to the housing of a gearbox includes an absorber mass having a first group of segments that are rotationally symmetrical to one another with respect to a rotational axis and/or central axis of the gearbox. The segments can be rigidly connected to one another. The vibration absorber can further include connectors that are rigidly connected to two segments each.

A torsional vibration damper has a hub part, also referred to as primary mass, which can be fastened on a drive shaft of an engine, and an inertia ring, also referred to as secondary mass, which surrounds the hub part in the radially outer region. A damping device is provided between the hub part and the inertia ring. The torsional vibration damper includes an additional torsion spring, wherein the additional torsion spring is axially aligned.

This soundproof wheel includes a soundproofing device (3) which is mounted to an inner peripheral surface (6) of a rim section (5) of the wheel. The soundproofing device (3) is provided with: a fixing ring (10) which is fitted in and fixed to a groove (8) formed in the inner peripheral surface (6); a first elastic body section (11A) which is stuck to an outer peripheral surface (10a) of the fixing ring (10), is disposed within the groove (8), and has a plurality of first elastic body pieces; an additional mass section (12) which is stuck to a side of the first elastic body section (11A) opposite to the fixing ring (10), is disposed within the groove (8), and has a plurality of additional mass pieces; and a second elastic body section (11B) which is stuck to a side of the additional mass section (12) opposite to the first elastic body section (11A), is disposed within the groove (8), and has a plurality of second elastic body pieces. The soundproofing device (3) includes a plurality of dynamic vibration absorbers. Each of the dynamic vibration absorbers has first and second elastic body pieces and an additional mass piece. This soundproof wheel allows for significant reduction in wheel vibration noise and is highly durable.

Apparatus and method for mounting an object are provided. The apparatus includes a clamp configured to attach to a strut, and a bracket coupled to the clamp. The bracket includes a first arm having a first end disposed proximal to the clamp and a second end disposed distal to the clamp, and a second arm having a first end disposed proximal to the clamp and coupled to the object, and a second end coupled to the second end of the first arm. The second arm is positioned between the first arm and the object.