A joystick device including a hollow housing having an endless boundary structure and a ceiling structure with an opening; a control-stick having a head portion and a stem portion, the hollow housing surrounding the stem portion with the head portion outside the hollow housing; and a plurality of biasing curved arm members extending outwardly from the stem portion and movable with the control-stick as a whole relative to the hollow housing along a plane at least substantially perpendicular to the stem portion. Each of the plurality of biasing curved arm members having a curved segment with a convex side directed towards a respective corresponding portion of the endless boundary structure so as to bias the stem portion when the control-stick is being moved towards said portion. The plurality of biasing curved arm members being distributed around the stem portion so as to cooperate with each other to centre the control-stick.

A torsional vibration damper in which collision noise resulting from collision of a rolling member against a rotary member is reduced. The torsional vibration damper comprises a restriction mechanism that establishes a restriction force in a direction to restrict the relative rotation between the rotary member and the inertia body, when the rolling member centrifugally pushed onto a raceway surface is pushed radially inwardly by the raceway surface toward a radially inner limit position of a guide section.

The invention relates to a tuned mass damper or vibration damper which, with the aid of an assembly (2) of a plurality of stacked, specially shaped or bent leaf springs (2.1), can be adapted over a certain range to the disturbance frequencies acting on a component to be damped or of the vibration system to be damped, the position of the damper mass (1, 34) being changed essentially only slightly. The invention relates in particular to one- and two-dimensionally effective tuned mass dampers. The tuned mass dampers according to the invention are suitable in particular for installations, vehicles and machines that undergo frequent changes in rotational speed, resulting frequently in disturbance frequencies that become noticeable, in particular, in the form of structure-borne sound, or other vibrations.

A vibration absorber for absorbing a vibration of a vibrating component is provided and includes: a spring system and an absorber mass arranged on the spring system. The spring system includes: a first spring element with a first core, and a second spring element with a second core. The first spring element is arranged on the second spring element such that the second core borders the first core, and the vibration absorber can be fastened using a fixing element to the vibrating component in which the vibration is to be absorbed. Furthermore, a method of producing the vibration absorber is further provided.

A tilger for a rotating body includes an annular body movably coupled to a rotatable portion of the rotating body. The tilger includes a spring interposed between the first annular body and the rotatable portion. Rotation of the rotatable portion relative to the annular body is to compress and decompress the spring. The tilger includes a ring positioned on an outer surface of the annular body and configured to expand as a rotational speed of the ring increases to decrease a total inertia of the annular body and the ring applied to the spring.

The invention makes available a device for damping the vibrations of a spindle of a machine tool, which spindle rotates about an axis of rotation, which device has a central longitudinal axis that is oriented coaxial to the axis of rotation of the spindle during use, and a housing that is provided for torque-proof coupling to the spindle and delimits a housing space that is configured as a ring space oriented coaxial to the central longitudinal axis and surrounds the central longitudinal axis, a ring-shaped damper mass that is arranged to move in the housing space relative to the central longitudinal axis and oriented coaxial to the central longitudinal axis in the rest state, and includes at least one spring element, by way of which the damper mass is movably held on the housing, with elastic resilience, with reference to the central longitudinal axis of the device, at least in the circumference direction of the damper mass. In that in the case of such a device, according to the invention, a gap is present between a circumference surface of the damper mass and an inner surface of the housing, which gap is filled with a viscous damper fluid, and in that, according to the invention, the clear width of the gap filled with the viscous fluid is adjustable, the damping effect can be adapted to the corresponding requirements in a simple manner.

A vibrational dampening element is attached to a component and configured to adjust the amplitude of oscillations of the component. The vibrational dampening element includes a mass. The mass includes a main body and a member extending from the main body. A casing that encapsulates the mass. A fluidic chamber defined between the mass and the casing. A first fluidic portion is disposed between a first side of the mass and the casing. The first fluidic portion includes a first accumulator portion directly neighboring the member. A second fluidic portion is disposed between a second side of the mass and the casing. The second fluidic portion includes a second accumulator portion directly neighboring the member. The first accumulator portion is in fluid communication with the second accumulator portion. The vibrational dampening element further includes a primary passage that extends between the first fluidic portion and the second fluidic portion.

A joystick device including a hollow housing having an endless boundary structure and a ceiling structure with an opening; a control-stick having a head portion and a stem portion, the hollow housing surrounding the stem portion with the head portion outside the hollow housing; and a plurality of biasing curved arm members extending outwardly from the stem portion and movable with the control-stick as a whole relative to the hollow housing along a plane at least substantially perpendicular to the stem portion. Each of the plurality of biasing curved arm members having a curved segment with a convex side directed towards a respective corresponding portion of the endless boundary structure so as to bias the stem portion when the control-stick is being moved towards said portion. The plurality of biasing curved arm members being distributed around the stem portion so as to cooperate with each other to centre the control-stick.

A power transmission device for a hybrid vehicle may include: a cover part mounted on a vehicle body; two motor parts embedded in the cover part; two rotor parts mounted in the respective motor parts and rotated; a transfer part selectively connected to the rotor part; a torsion damper part coupled to the transfer part; a clutch part configured to selectively connect any one of the rotor parts to the transfer part; and an output part connected to the clutch part and configured to discharge power to a transmission, wherein any one of the rotor parts is connected to the torsion damper part.

A vibration damper is provided with two rotating members, i.e. an oscillating inertial flywheel and a member to be damped driven by a torque following a torque path between a driving member and a driven member, wherein the inertial flywheel is connected kinematically to the torque path between the driving member and the driven member solely by way of the member to be damped. Connecting modules between the two rotating members permit a relative angular displacement θ between the two rotating members on the two sides of a reference relative angular position. Each connecting module is provided with a roller associated with a first of the two rotating members and a cam track connected resiliently by a resilient element to a second of the two rotating members.