A passive oscillation damper (8), in particular for a switch cabinet (2), includes a supporting structure (12) having a longitudinal direction (y) and a transverse direction (x) and with a central oscillating mass (14) mounted by means of spring elements (20, 22, 24, 26) so as to be able to oscillate in the longitudinal direction (y) and in the transverse direction (x). At least one peripheral oscillating mass (40, 42) is mounted on the central oscillating mass (14) so as to be slidable in the longitudinal direction (y) and to be movable relative to the central oscillating mass (14). At least one peripheral oscillating mass (44, 46) is mounted on the central oscillating mass (14) so as to be slidable in the transverse direction (x) and to be movable relative to central oscillating mass (14).

A drivetrain for motor vehicle including an electric motor and a reduction mechanism designed to transmit the driving torque to the wheels of the motor vehicle. The electric motor includes a rotor equipped with a rotor shaft, the rotor shaft being rotationally coupled to a primary shaft of the reduction mechanism. The drivetrain further includes a dynamic absorber in torsion, the dynamic absorber in torsion having a support element, an inertial mass which is mounted with the ability to rotate about an axis X with respect to the support element and elastic members which oppose the relative rotation of the inertial mass with respect to the support element about said axis X.

The invention relates to a flywheel for stabilising the position of a spacecraft, comprising a hub means (1) for fastening the flywheel, a flywheel ring (4), which externally surrounds the hub means (1) circumferentially at a distance, a support means (3) for supporting the flywheel ring (4) on the hub means (1), and a vibration damping device (6, 8) having a tuned mass damper means (8) which is axially movable back and forth relative to the flywheel ring with respect to a rotation axis of the flywheel.

A vehicle transmission system component including a first subassembly having an input and an output, between which a torque can be transmitted. A second subassembly forms a pendulum-type damping device, and disposed outside the path of the torque transmitted by the first subassembly. The first and the second subassemblies are connected to one another by at least one connecting element capable of being elastically deformed circumferentially.

A dynamic vibration absorbing device for an automobile can be on an output-side member of a torque converter. The dynamic vibration absorbing device includes a rotary member, a mass part, and an elastic member. The rotary member is fixed to the output-side member. The rotary member can be rotated about a rotational center of the output-side member. The mass part includes a first accommodation part. The mass part is for attenuating vibration of the output-side member by rotating about the rotational center relative to the rotary member. The elastic member is held by the first accommodation part. The elastic member elastically couples the rotary member and the mass part in a rotational direction. The elastic member is for generating a hysteresis torque by sliding against the first accommodation part in rotation of the rotary member.

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.

A damper (10) includes a housing (11) and a rotor (16) combined with the housing (11) so as to be capable of rotating relative to the housing (11). The damper (10) includes an attenuating medium (90) filled in a rotation area inside the housing (11) wherein the rotor (16) rotates, and added with viscoelasticity by a viscoelasticity treatment; and an enclosure portion (80) provided outside the rotation area of the rotor (16), and communicating with the rotation area.

A method for protecting a dual mass flywheel DMF, by detecting, when the engine in running, that the DMF is entering into resonance, the DMF being arranged between an internal combustion engine and a gearbox of a vehicle, comprising the following steps: • Determining the average rotational speed (Vvil.sub.moy) of the crankshaft, over time, over a predetermined given period, as a first parameter constituting a risk of the DMF entering into resonance, • Measuring the maximum instantaneous rotational speed and the minimum instantaneous rotational speed of the crankshaft, the difference defining the maximum amplitude (Amp.sub.Vvil) of the rotational oscillations of the crankshaft, over the period, as a second parameter constituting a risk of the DMF entering into resonance, • Detecting when the DMF is entering into resonance from a determined combination of values of the first and second parameters, over the period, • limiting or cutting off the fuel injection in the cylinders after said detection.

A vibration damping device for a machine tool spindle is provided. An annular support plate is mounted at a lower portion of a distal end of the spindle, a plurality of support bars is fixed to the support plate in a vertical direction and installed in a longitudinal direction of the spindle adjacent to an outer periphery of the spindle, a pair of weight disks stacked by a plurality of arc-shaped disks made of a tuned mass member is fixed to be in close contact with the outer periphery of the spindle, facing each other, and a damping sheet made of an elastic member is inserted between the outer periphery of the spindle and the weight disks. The vibration damping device of the present invention may maximize a vibration damping effect by installing the vibration damping device at a position closest to the spindle where a vibration occurs. Furthermore, the vibration damping device of the present invention may effectively attenuate a variety of vibration phenomena having various resonant frequencies of a machine tool spindle by constituting the vibration damping device in a plurality of modular types which have different resonant frequency bands, respectively.

Devices, systems, and methods for damping vibration of a structural component or power-transmission shafts are disclosed. Damping devices, systems, and methods utilize a lightweight damping device, which is targeted at reducing the resonant amplitude of the first several beaming modes and/or torsional modes of bending a structural component comprising a hollow shaft or strut. The damping device includes a stiff concentric tube with damping elements disposed at each end. The device is inserted within the original structural component or shaft and attached thereto. When the primary shaft undergoes bending due to modal characteristics, the damping elements react to dissipate energy, which effectively reduces the resonant amplitude.