A shaking unit for the generation of one-dimensional oscillating movements of a machine part mass is provided having a coupling part for mechanical coupling to the machine part mass, a counter-mass which is coupled resiliently to the coupler part and, via the latter, to the machine part mass, and a drive system which acts in a sprung manner between the coupler part and the counter-mass. The coupling part may surround the counter-mass as a frame. At least one of two pneumatic springs of the drive system, which are arranged on both sides of the counter-mass, is loaded with a minimum and/or with a maximum load pressure of the pneumatic springs depending on an oscillation state.

The present invention relates to an earthquake-resistant light tower with a tuned mass damper, in which a tuned mass damper is installed in a head part of a light apparatus installed on the top of a tower to absorb an earthquake or other vibration, thereby protecting a tower from vibration.

A system includes a vibration damper coupled for rotation with a rotating body. The vibration damper includes one or more fluid pockets. A reactive fluid is arranged in the one or more fluid pockets. The reactive fluid is configured to undergo a property change upon being exposed to a selected force. A force producing mechanism is fixedly mounted relative to the vibration damper, the force producing mechanism being operable to selectively produce the selected force.

A liquid absorber is for absorbing and damping vibrations in structures, in particular in slender, vertically oriented structures. It is therefore an object to overcome the disadvantages of the prior art and to provide a liquid absorber which lessens the sloshing effect of a fluid in the liquid absorber. A further object is to provide a liquid absorber which achieves an increase in the damping ratio for containers with sloshing lengths of more than 80 cm. A further object is to enable fine adjustments to be made with regard to the damping ratio and to develop a vibration absorber which has optimal damping properties (Den Hartog) and considerably improves the response behavior over a broad frequency spectrum.

A system or structure subject to external mechanical dynamic loading excitations propagated within the system or structure comprising a fluid filled structure and a fluid volume operable to facilitate fluid flow about at least part of the structure. Excitations within the structure can be propagated throughout. The system can further comprise a tuned mass damper (TMD) located within the fluid volume. The TMD can leverage the viscous properties of the fluid to attenuate the excitations within the structure. The TMD can comprise a mass and a spring operably connected to the mass. The TMD can further comprise a fluid resistance facilitating fluid flow about the mass and the spring for damping and a secondary tuning device operably connected to at least one of the mass and the spring and the supporting fluid-filled structure.

The present invention relates to a structural damper 1 for protecting structures against vibrations, comprising a first pendulum 3 having a first pendulum mass 3a, a second pendulum 4 having a second pendulum mass 4a, a coupling device 5 and a damping device 6. The coupling device 5 is disposed between the first pendulum mass 3a and the second pendulum mass 4a, and is configured to couple the first pendulum mass 3a to the second pendulum mass 4a in an effective direction of the structural damper 1 and to allow relative movement between the first pendulum mass 3a and the second pendulum mass 4a in a direction of movement angled with respect to the effective direction. The damping device 6 is disposed between the first pendulum mass 3a and the second pendulum mass 4a, and is configured to damp relative movement in the direction of movement between the first pendulum mass 3a and the second pendulum mass 4a.

The present invention relates to an earthquake-resistant light tower with a tuned mass damper, in which a tuned mass damper is installed in a head part of a light apparatus installed on the top of a tower to absorb an earthquake or other vibration, thereby protecting a tower from vibration.

A system or structure subject to external mechanical dynamic loading excitations propagated within the system or structure comprising a fluid filled structure and a fluid volume operable to facilitate fluid flow about at least part of the structure. Excitations within the structure can be propagated throughout. The system can further comprise a tuned mass damper (TMD) located within the fluid volume. The TMD can leverage the viscous properties of the fluid to attenuate the excitations within the structure. The TMD can comprise a mass and a spring operably connected to the mass. The TMD can further comprise a fluid resistance facilitating fluid flow about the mass and the spring for damping and a secondary tuning feature operably connected to at least one of the mass and the spring and the supporting fluid-filled structure.

A system or structure subject to external mechanical dynamic loading excitations propagated within the system or structure comprising a fluid filled structure and a fluid volume operable to facilitate fluid flow about at least part of the structure. Excitations within the structure can be propagated throughout. The system can further comprise a tuned mass damper (TMD) located within the fluid volume. The TMD can leverage the viscous properties of the fluid to attenuate the excitations within the structure. The TMD can comprise a mass and a spring operably connected to the mass. The TMD can further comprise a fluid resistance facilitating fluid flow about the mass and the spring for damping and a secondary tuning feature operably connected to at least one of the mass and the spring and the supporting fluid-filled structure.

A tunable mass-damping apparatus may include a housing having an interior surface, an interior volume containing a fluid, and an axis. The housing may be configured to be coupled to a wind tunnel model. The apparatus may further include a mass configured to move back and forth in the interior volume along the axis. The mass may be configured to make an airtight seal with the interior surface of the housing, thereby dividing the interior volume into an upper chamber and a lower chamber. The apparatus may include a passage fluidly connecting the upper chamber and the lower chamber and a spring configured to exert a position-dependent force upon the mass. The spring may be characterized by a variable spring constant chosen based on a variable natural frequency of a support structure of the wind tunnel model. The variable spring constant may be established with a nickel-titanium alloy spring heated to at least one calibrated temperature that corresponds to a predetermined spring constant.