A dynamic vibration absorber is disclosed. The dynamic vibration absorber includes a rotatable first hub, an inertia member, a plurality of elastic members, a plurality of sliders, and a guide member. The inertia member is disposed on an outer peripheral side of the first hub. The inertia member is rotatable relative to the first hub. The plurality of elastic members radially extend between the first hub and the inertia member. The plurality of elastic members are elastically deformable and elastically couple the first hub and the inertia member in a rotational direction. The plurality of sliders are radially movable along the plurality of elastic members. The plurality of sliders are configured to contact the plurality of elastic members. The guide member radially move the plurality of sliders. The guide member determines radial positions of the plurality of sliders.

In the centrifugal pendulum damper, a plurality of pendulums are swingably supported on a rotating body. The pendulum includes a swinging shaft serving as the swing center and a rolling shaft including a rolling surface on the outer periphery thereof. The rotating body includes a plurality of pendulum support portions, and the pendulum support portion includes a swinging shaft guide portion that guides the swinging shaft in a radial direction of the rotating body, and a rolling shaft guide portion that is in rolling-contact with the rolling surface of the rolling shaft to cause the pendulum to swing around the swing axis.

A torsional vibration damper having enhanced damping performance is provided. A first gear held in the holding member includes a first engagement member situated in an opposite side of a fluid coupling and a second engagement member situated between a holding member and the fluid coupling. A second gear is meshed with the first engagement member, and a third gear is meshed with the second engagement member. The second gear is integrated with the input member, the third gear is integrated with the inertial mass, and the holding member is integrated with the output member.

A rotary device includes a first rotor, a second rotor, a centrifugal element, and a first rolling member. The first rotor includes an accommodation portion having first and second guide surfaces. The first and second guide surfaces face both sides in a circumferential direction. The first rotor is disposed to be rotatable. The second rotor is disposed to be rotatable with and relative to the first rotor. The centrifugal element is disposed within the accommodation portion. The centrifugal element is disposed to be radially movable by a centrifugal force acting thereon in rotation of the first or second rotor. The centrifugal element rotates about a rotational axis thereof in radial movement thereof. The first rolling member is disposed between the first guide surface and the centrifugal element. The first rolling member rolls on the first guide surface in accordance with rotation of the centrifugal element about the rotational axis thereof.

In a vibration damping device 20, the moment of inertia J.sub.1 of a driven member 15, the moment of inertia J.sub.2 of an inertial mass body 23, the mass m of crank members 22, the distance L3 between the center of gravity G of the crank member 22 and the fulcrum of swinging of the crank member 22 with respect to the inertial mass body 23, and the distance L4 between this fulcrum and the center of rotation RC are determined so that torque fluctuation of an object for which vibration is to be damped, which is derived based on angular displacement and angles obtained by solving an equation of motion for the driven member 15 and an equation of motion for the entire vibration damping device 20 is equal to a target value.

A torque fluctuation inhibiting device includes a mass body. The mass body disposed to be rotatable with a rotor and be rotatable relatively to the rotor. Each of a plurality of centrifugal elements is radially movable by a centrifugal force that acts thereon in rotation of the rotor and the mass body. When a relative displacement is produced between the rotor and the mass body in a rotational direction while the centrifugal force is acting on the each of the plurality of centrifugal elements, each of a plurality of cam mechanisms converts the centrifugal force into a circumferential force directed to reduce the relative displacement. A plurality of restriction members allow the plurality of centrifugal elements to move in actuation of the plurality of cam mechanisms, and restrict the plurality of centrifugal elements from moving radially inward in non-actuation of the plurality of cam mechanisms.

A pump system may include a pump, a driveshaft, driving equipment, and a vibration dampening assembly configured to reduce pump-imposed high frequency/low amplitude and low frequency/high amplitude torsional vibrations. The pump may have an input shaft connected to the driveshaft. The driving equipment may include an output shaft having an output flange connected to the driveshaft. The driving equipment may be configured to rotate the driveshaft to rotate the input shaft of the pump therewith. The vibration dampening assembly may include one or more flywheels operably connected to the input shaft and configured to rotate therewith.

A dynamic damper device for absorbing a torsional vibration includes a rotary part, an inertia part, and an elastic part. The rotary part is a part to which the torsional vibration is transmitted, and is rotatable about a rotational center. The inertia part is provided on the rotary part so as to be movable in a radial direction with respect to the rotary part by a centrifugal force and be movable in a circumferential direction with respect to the rotary part by the torsional vibration. The elastic part couples the rotary part and the inertia part.

A dynamic vibration absorber is disclosed. The dynamic vibration absorber includes a rotatable first hub, an inertia member, a plurality of elastic members, a plurality of sliders, and a guide member. The inertia member is disposed on an outer peripheral side of the first hub. The inertia member is rotatable relative to the first hub. The plurality of elastic members radially extend between the first hub and the inertia member. The plurality of elastic members are elastically deformable and elastically couple the first hub and the inertia member in a rotational direction. The plurality of sliders are radially movable along the plurality of elastic members. The plurality of sliders are configured to contact the plurality of elastic members. The guide member radially move the plurality of sliders. The guide member determines radial positions of the plurality of sliders.

A damper device includes an input element to which a torque from an engine is transmitted; an intermediate element; an output element; a first elastic body arranged to transmit a torque between the input element and the intermediate element; a second elastic body arranged to transmit a torque between the intermediate element and the output element; a rotary inertia mass damper that includes a mass body rotating in accordance with relative rotation between the input element and the output element and that is arranged between the input element and the output element to be parallel to a torque transmission path including the first elastic body, the intermediate element and the second elastic body; and an attenuation mechanism configured to attenuate resonance of the intermediate element.