A vibration-proof bush capable of suppressing incomplete fitting of an upper bush and a lower bush. The vibration-proof bush includes an upper bush configured to be mounted on a vehicle body side and a lower bush configured to be fitted to the upper bush are provided, wherein the vibration-proof bush includes interference portions configured to interfere with each other in a process of fitting the lower bush to the upper bush, and the interference portions form a fitting-sound generation structure in which a sound is generated, when the lower bush is fitted to the upper bush during temporary assembling.

Intermediate plate apparatus and related damper assemblies for use with vehicles are disclosed. A disclosed vehicle torque converter includes a clutch and a torsional vibration damper configured to receive a torque from the clutch when the clutch is engaged and dampen a torsional vibration in the torque. The torsional vibration damper includes a driven plate, a retainer plate, a first spring member, a second spring member, and an intermediate plate positioned radially outward relative to the driven plate and the retainer plate. The intermediate plate includes a body that defines an annular cavity though which the first and second spring members extend. The body is configured to engage inner and outer radial portions of the respective first and second spring members to maintain bend radii of the respective first and second spring members.

Systems and methods for damping torsional oscillations of downhole systems are described. The systems include a downhole drilling system disposed at an end of the downhole system in operative connection with a drill bit. A damping system is installed on the downhole drilling system, the damping system having at least one damper element configured to dampen at least one HFTO mode. At least one mode-shape tuning element is arranged on the drilling system. The at least one mode-shape tuning element is configured and positioned on the drilling system to modify at least one of a shape of the HFTO mode, a frequency of the HFTO mode, an excitability of the HFTO mode, and a damping efficiency of the at least one damper element.

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 damper device includes a first rotor, a second rotor, a plurality of elastic members and a stopper mechanism. The stopper mechanism includes a plurality of first cutouts, a plurality of second cutouts and a plurality of stop members. A pair of the first and second cutouts is provided on both circumferential sides of each of a plurality of accommodation portions of the second rotor so as to circumferentially extend therefrom. The stop members are fixed to the first rotor. Each stop member is circumferentially movable within the pair of the first and second cutouts. The second rotor includes a first protruding portion circumferentially protruding on one of a pair of pressing surfaces of each accommodation portion. Each of the first cutouts, which is a hole, extends at an end thereof located closer to each accommodation portion toward the first protruding portion.

In an aspect, an isolation device is provided for a belt and a component shaft in an engine. The device includes a hub, a pulley, an isolation spring and a damping member that is fixed rotationally relative to the hub and is engageable frictionally with the pulley. Torque transmission through the spring below a selected non-zero torque, irrespective of hub load on the pulley, drives a change in radius of the helical coils of the spring that is sufficiently small that the spring avoids pressing the damping member against the pulley. Torque transmission through the spring above the selected non-zero torque, irrespective of hub load on the pulley, drives a change in radius of the helical coils that is sufficiently large that the isolation spring applies a radial force to press the damping member against the pulley so as to generate frictional damping.

In an aspect, a power transfer device, such as a decoupler, is provided for transferring torque between a shaft and a belt. The device includes: a hub configured to couple to the shaft, a pulley rotatably coupled to the hub that includes a power transmitting surface configured to engage the belt, an isolation spring to transfer a rotational load from one of the pulley and the hub to the other of the pulley and the hub, optionally a one-way clutch to permit overrunning of one of the pulley and the hub relative to the other of the pulley and the hub in a first direction, and a damping member positioned to be driven into frictional engagement with a friction surface by a force from the isolation spring acting on the damping member that varies based on the rotational load transferred by the isolation spring.

A torsional vibration damper arrangement for a drive train of a motor vehicle includes a torsional vibration damper having an input flange, a first output flange, a second output flange, a hub, a first connecting element, and a second connecting element. The first output flange is rotatable relative to the input flange about an axis of rotation against a spring device. The first connecting element lies on a first radius relative to the axis of rotation and connects the first output flange, the second output flange, and the hub in rotationally fixed and form-fitting or force-fitting manner for torque transmission to a further component. The second connecting element is disposed at least partially radially inside the hub and connects the hub to the second output flange in a force-fitting or form-fitting manner.

A torque fluctuation inhibiting device is disclosed. The torque fluctuation inhibiting device includes an input member, an elastic member, a mass body and a centrifugal element. The input member includes a pair of input plates disposed in axial alignment. The input member is disposed to be rotatable. The elastic member is held by the pair of input plates. The mass body is disposed to be rotated with the input member and be rotatable relative to the input member. The centrifugal element is disposed to be radially movable by a centrifugal force acting thereon in rotation of the input member. The centrifugal element is disposed between the pair of input plates.

A vibration isolating coupler including a first coupler portion, a second coupler portion including an external surface and an internal surface portion, and a vibration isolating portion extending between the first coupler portion and the second coupler portion. The vibration isolating portion including a first solid annular portion and a second solid annular portion. The vibration isolating portion including a plurality of slots extending from the first solid annular portion toward the second solid annular portion forming a plurality of vibration isolating elements. Each of the plurality of vibration isolating elements is disconnected from adjacent ones of the plurality of vibration isolating elements by a corresponding one of the plurality of slots. The plurality of vibration isolating elements enabling torsional rotation of the first coupler portion relative to the second coupler portion.