A center bearing assembly for a multi-piece propeller shaft includes a stud yoke extending along an axis A between first and second stud yoke ends to define a central stub shaft rotatable about the axis A. A rotatable weld collar is operably connected to the second stud yoke end of the central stub shaft for simultaneous rotation therewith. The rotatable weld collar includes a body extending from a first collar end disposed adjacent the central stub shaft to a second collar end to define an exterior surface. A tuned damper extends radially outwardly from the exterior surface of the rotatable weld collar for reducing noise, vibration, and/or harshness (NVH) generated during operation of the multi-piece propeller shaft. A first shaft segment is operably connected to the rotatable weld collar and a second shaft segment is operably connected to the stud yoke for transferring a rotational force therebetween.

A drive member of a damper device includes a first input plate member and a second input plate member that rotatably support a plurality of pinion gears of a planetary gear of a rotary inertia mass damper. A driven member includes an outer teeth gear portion that meshes with the pinion gear in an outer circumferential portion thereof and is disposed between the first and the second input plate members in an axial direction so as to work as a sun gear of the planetary gear. A stopper is configured to restrict the relative rotation between the drive member and the driven member and includes a contact portion arranged in the outer circumferential portion of the driven member so as to contact with the first input plate member.

A drive member of a damper device includes a first input plate member and a second input plate member that rotatably support a plurality of pinion gears of a planetary gear of a rotary inertia mass damper. A driven member includes an outer teeth gear portion that meshes with the pinion gear in an outer circumferential portion thereof and is disposed between the first and the second input plate members in an axial direction so as to work as a sun gear of the planetary gear. A stopper is configured to restrict the relative rotation between the drive member and the driven member and includes a contact portion arranged in the outer circumferential portion of the driven member so as to contact with the first input plate member.

A damper device is attached to a rotating shaft to suppress amplitude at resonance of the rotating shaft. The damper device includes: a damper housing formed annularly and concentrically with the rotating shaft; a plurality of mass bodies annularly arranged around the rotation shaft inside of the damper housing and configured to be movable in the diameter direction by centrifugal force; an annular elastic body, formed of a circular spring-shaped elastic body abutting on the outside of the plurality of the mass bodies, so as to bias the mass body inward; and a biasing member, being a leaf spring-shaped elastic body abutting on the outside of the annular elastic body, so as to bias the annular elastic body inward.

A dynamic damper is coupled to an intermediate member of a damper device. A drive member of the damper device has additional abutment portions coupled to end portions of vibration absorption springs of the dynamic damper before both first and second inter-element stoppers operate. The second inter-element stoppers operate before the first inter-element stoppers operate and at least by the time when the additional coupling portions are coupled to end portions of the vibration absorption springs. Outer springs and the vibration absorption springs act in parallel to transfer torque after the additional coupling portions are coupled to end portions of the vibration absorption springs.

A torsional vibration absorber for a vehicle is provided. The torsional vibration absorber including a front pilot bearing adapted to couple with a vehicle shaft. A spring member is coupled to the front pilot bearing. An inertia ring having an inner surface is operably coupled to the spring member, wherein the front pilot bearing is centrally disposed along the length of the inertia ring. A rear pilot bearing is adapted to couple with the vehicle shaft, the rear pilot bearing having a portion adjacent the inner surface at one end of the inertia ring.

A torsional vibration damper includes a planetary rotary unit and an elastic body that couples two rotary elements of three rotary elements so that the two rotary elements can rotate relatively to each other. The torsional vibration damper includes a shaft supporting member by which a rotation center axis of at least any one rotary element of the two rotary elements and a rotation center axis of the rotary element other than the planetary rotary unit and the two rotary elements are held on the same axis. The shaft supporting member has a holding section that is disposed in a position between fellow planetary rotary elements and not making contact with the planetary rotary elements and that fits with and thereby suppresses movement of the rotary element other than the planetary rotary unit and the two rotary elements in the axial direction.

A power transmission device is disposed between an engine and a transmission so as to be capable of attenuating fluctuations in torque. The device includes an input rotary part, an output rotary part, an elastic part, an inertia mass part and an engaging part. The torque is inputted to the input rotary part. The output rotary part is rotatable relatively to the input rotary part. The elastic part elastically couples the input rotary part and the output rotary part in a rotational direction. The inertia mass part is movable in the rotational direction. The engaging part is engaged with the elastic part and the inertia mass part. The engaging part actuates the elastic part by relative rotation between the input rotary part and the output rotary part and movement of the inertia mass part.

A drivetrain having an active torsional vibration damping and a method for carrying out the active torsional vibration damping, having an internal combustion engine being affected by torsional vibrations and having a crankshaft, a torsional vibration damper that is operatively connected to the crankshaft and has at least one operating point of low vibration isolation of the torsional vibrations and has a primary inertial mass associated with the crankshaft and an inertial mass associated with a gear input shaft of a gearbox, the inertial mass being rotatable relatively and limitedly with respect to the primary inertial mass against the action of a spring device. The drivetrain also includes an electric motor having a rotating mass operatively connected to the gearbox input shaft, and a control unit, the spring device being formed by linear springs, the rotating mass of the electric motor being designed as a secondary inertial mass.

An apparatus for damping of a flywheel, which is configured so that a second mass may rotate in a direction for offsetting torsional vibration of an engine transmitted to a first mass through a damping spring. The apparatus includes: guides disposed between damping springs and guiding the damping springs extending/contracting in a rotational direction by a damping operation; and a third mass arranged coaxially with the second mass, with one end connected to the guide, and relatively rotating in a direction for offsetting torsional vibration of the engine transmitted to the second mass.