An apparatus for suppressing oscillations of an oscillating body includes a magnetic base and a magnetic stabilizing mass pivotably coupled to the magnetic base by a pivot assembly. The pivot assembly defines a pivot axis about which the magnetic stabilizing mass is pivotable, relative to the magnetic base, between a first position and a second position. The magnetic stabilizing mass has an equilibrium position between the first position and the second position. The magnetic base produces magnetic fields that magnetically repel the magnetic stabilizing mass away from the first position at least when the magnetic stabilizing mass is offset from the equilibrium position toward the first position, and that magnetically repel the magnetic stabilizing mass away from the second position at least when the magnetic stabilizing mass is offset from the equilibrium position toward the second position.

A tunable mass damping device, including a connecting, a weighted assembly, and a top connecting assembly connecting an upper end of the connecting rod with a tower beam of a tower and including an anti-rotation mechanism. The anti-rotation mechanism includes: a laterally extending fixing plate fixedly connected with the tower beam through a longitudinally extending supporting member; a laterally extending first movable plate arranged under the fixing plate and fixedly connected with the upper end of the connecting rod; and two connecting shafts spaced apart from each other. Each of the connecting shafts has a lower end fixedly connected to the first movable plate, and an upper end inserted into the fixing plate and connected therewith through a connecting head. The connecting head includes an intermediate elastic layer arranged between inner and outer sleeves of the connecting head.

A tunable mass damping device, including a connecting, a weighted assembly, and a top connecting assembly connecting an upper end of the connecting rod with a tower beam of a tower and including an anti-rotation mechanism. The anti-rotation mechanism includes: a laterally extending fixing plate fixedly connected with the tower beam through a longitudinally extending supporting member; a laterally extending first movable plate arranged under the fixing plate and fixedly connected with the upper end of the connecting rod; and two connecting shafts spaced apart from each other. Each of the connecting shafts has a lower end fixedly connected to the first movable plate, and an upper end inserted into the fixing plate and connected therewith through a connecting head. The connecting head includes an intermediate elastic layer arranged between inner and outer sleeves of the connecting head.

The present invention relates to an elastic metamaterial for reducing vibrations of a flexible structure such as a main cable of a tether system for controlling an orbit of a satellite revolving around a planet, and a method for improving a vibration reduction performance thereof, and more particularly, to an elastic metamaterial having an improved precision, in which a ratio of a cross-sectional area of a pendulum ring may be adjusted to maintain a frequency characteristic other than a band gap generated due to the elastic metamaterial even in a state where a mass of the pendulum ring is not changed, and a band gap (R_ring) generated due to the pendulum ring of the elastic metamaterial and a band gap (R_beam) generated due to the elastic beams may be combined into one band gap to expand a vibration damping range, and a method for improving a vibration reduction performance thereof.

Two or more target points different in amplitude in a natural mode, which exist in a housing of an object to be damped such as an engine, a gearbox, motors, or the like are located. Among these target points, an arm is fixed at a position relatively small in amplitude, and a vibration absorber provided at the free end of the arm is pressed against a position (relatively large in amplitude. When vibrations occur in the object, the vibration absorber holds the target point relatively large in amplitude while the arm is following the vibrations of the target.

A damper unit for use in a vibration-reducing assembly for a steering wheel is disclosed. The damper unit includes a slider configured, upon horn activation, to slide on a guide shaft. A damper element made from an elastomeric material is arranged on a first part of the slider. A molded horn spring element is molded directly on a second part of the slider and is configured to exert a spring force on the slider. The damper unit provides a unitary structure providing both a vibration damping function and a horn spring function in one single assembly unit, reducing the number of components to assemble. A vibration-reducing damper assembly including one or more such damper units is also disclosed, as well as a method of making such a damper unit.

A damper unit for use in a vibration-reducing assembly for a steering wheel is disclosed. The damper unit includes a slider configured, upon horn activation, to slide on a guide shaft. A damper element made from an elastomeric material is arranged on a first part of the slider. A molded horn spring element is molded directly on a second part of the slider and is configured to exert a spring force on the slider. The damper unit provides a unitary structure providing both a vibration damping function and a horn spring function in one single assembly unit, reducing the number of components to assemble. A vibration-reducing damper assembly including one or more such damper units is also disclosed, as well as a method of making such a damper unit.

The hand-held power tool has a tool holder (2) for holding a tool (4) along a working axis (12). A hammer mechanism (6) has a striker (15) that is moved periodically along the working axis at an impact rate. A drive control (18) of the hammer mechanism (6) sets the impact rate to a set point value. A vibration absorber (19) has an oscillator (21) that moves along the working axis (12) about a resting position and one or multiple springs (20) that drive the oscillator (21) back into the resting position. A calibration phase comprises the following steps: detection of an acceleration using the acceleration sensor (24); determination of a minimum of the acceleration by varying the impact rate in a range of between 90% and 110% of the set point value; and adjusting the set point to the impact rate associated with the ascertained minimum.

The hand-held power tool has a tool holder (2) for holding a tool (4) along a working axis (12). A hammer mechanism (6) has a striker (15) that is moved periodically along the working axis at an impact rate. A drive control (18) of the hammer mechanism (6) sets the impact rate to a set point value. A vibration absorber (19) has an oscillator (21) that moves along the working axis (12) about a resting position and one or multiple springs (20) that drive the oscillator (21) back into the resting position. A calibration phase comprises the following steps: detection of an acceleration using the acceleration sensor (24); determination of a minimum of the acceleration by varying the impact rate in a range of between 90% and 110% of the set point value; and adjusting the set point to the impact rate associated with the ascertained minimum.

The invention relates to an industrial truck comprising

a chassis (6),
a mast (8) arranged on the chassis (6) in an upright position, a load-carrying apparatus (36), which has at least one load-receiving means (42) for receiving a load that is to be transported,
a support structure (9) that supports the load-carrying apparatus (36) on the mast (8) and can be moved, together with the load-carrying apparatus (36), upwards and downwards on the mast (8), and comprising
a device (54) for reducing vibrations,
wherein the device (54) for reducing vibrations has at least one additional mass body (60), which is supported by the mast (8) or the components connected thereto and is not constantly rigidly coupled to the mast (8) or the support structure (9) or the load-carrying apparatus (36), but is movably mounted by means of a bearing arrangement (62) such that it is movable relative to the mast (8) in response to mast vibrations, in particular to mast vibrations having horizontal vibration components, in order to counteract mast vibrations.