An impulse damper device, which is specifically provided for the construction or the dismantling of tall, slim constructions, in particular towers and preferably towers of wind turbines, in order to minimize or eliminate undesired vibration states, which often occur during the construction or taking apart and lead to large increases in the vibration amplitudes of the vibration system. The impulse tuned mass dampers are preferably provided for temporary mobile use, but, in principle, are also suitable for permanent use.

Inerters with friction disk assemblies, and aircraft hydraulic systems and aircraft including the same. An inerter comprises an inerter housing containing an inerter fluid, a threaded shaft extending within the inerter housing and fixed relative to the first terminal, and an inerter rod extending at least partially within the inerter housing and fixed relative to the second terminal. The inerter further includes a friction disk assembly that, together with the inerter fluid, is configured to damp a motion of the second terminal relative to the first terminal. The friction disk assembly includes a fixed portion and a rotating portion, and is configured such that rotation of the rotating portion generates a frictional torque that opposes the rotation of the rotating portion. In some examples, the inerter is a component of a hydraulic actuator, an aircraft hydraulic system including the hydraulic actuator, and/or an aircraft including the aircraft hydraulic system.

A damping system for damping rotary movements of a tailing arm. The system includes a chassis, a main shaft, and a rotary damping mechanism. The rotary damping mechanism includes a first externally-threaded gear attached fixedly to the main shaft, a guide rail attached fixedly to the chassis, a linear shock absorber, an internally-threaded gear associated with the first externally-threaded gear, and a first actuator configured to decouple the first externally-threaded gear from the linear shock absorber and couple the first externally-threaded gear with the linear shock absorber.

A portable device for precision plasma and oxy-fuel torch cutting is provided. Versions of an example portable cutting torch tool guide the gun of a cutting torch to make precision linear cuts or curved cuts in a metal workpiece. In an implementation, the device is a gun for a cutting torch, with an integrated rail follower and adjustable vertical and horizontal offsets from a workpiece. The cutting torch tool may use various kinds of rails for stable cuts, with optional movement damping, motorized drive, servos for vertical and horizontal offset, and remote control with user interface.

An anti-tail buffet device leverages existing rotorcraft components to attenuate a tailboom's lateral ringing from air buffeting. Anti-buffet masses are tuned to the tailboom's lateral-bending or torsional natural frequency such that when lateral motion occurs, the response at this frequency is cancelled by the anti-buffet system, preventing this vibration from entering into the tailboom structure. Motion stops prevent over-travel. The mass of the tail rotor actuator is soft-mounted, such that its natural frequency is equal to the tailboom's lateral-bending or torsional natural frequency. When lateral loading occurs on the tail rotor disk, the lateral response at this frequency is attenuated by the soft-mounted tail rotor actuator, thereby preventing the vibration in the tailboom structure.

A vibration absorber which, in addition to a main mass which is fixed thereto and moved along a curved trajectory by a driving mechanism, comprises a substantially smaller variably adjustable rotating flywheel mass which is moved together with the main mass along the trajectory thereof, enabling the adjustment of the frequency of the absorber. The rotating flywheel mass is driven by a novel belt device independently of the driving mechanism. A rotating vibration absorber which, along with the main mass and the rotating flywheel mass, comprises its own damping unit, such as an eddy-current damping unit.

The present invention provides a method and apparatus for energy absorption and vibrational dampening in a horizontal plane. According to a first preferred embodiment, the present invention discloses an apparatus for damping vibration of a pole which includes a housing with a horizontal floor having an inward curved surface for achieving vibration attenuation at a middle portion thereof to form an enclosed chamber. According to a further aspect of the first embodiment, at least one damping weight is preferably disposed in the inward curved surface and is preferably substantially spherical in shape. According to a further preferred embodiment, at least one dampening weight of the present may preferably include a hollow, inner cavity. According to further aspects of the present invention, the dampening weight preferably may further include a granular material located within the inner cavity.

The rotary inertial mass damper has a configuration in which the rotary shaft of the oil-pressure motor rotates due to oil pressure of operating oil that is extruded from an oil chamber through reciprocating movement of the piston rod, and viscosity resistance is produced in operating oil that circulates in the connection pipes.

Systems, devices, and methods for active vibration control using circular force generators. In one aspect, a vehicle includes a vehicle frame, a cabin, an engine, and a number of vibration control devices mounted on the vehicle frame. Each vibration device includes a circular force generator comprising at least one mass and at least one motor configured to rotate the mass. The vibration control devices are configured to perform active vibration control to reduce noise and/or vibration within the cabin resulting from the engine deactivating a subset of cylinders in operation.

A kit for a helicopter is described, the helicopter comprising a fuselage and a rotor; the kit comprises at least one device adapted to dampen the vibrations transmitted from the rotor to the fuselage and to be interposed between the fuselage and the rotor; the device, in turn, comprises a first threaded element operatively connectable to the rotor and adapted to, in use, vibrate parallel to a first axis; a second threaded element operatively connectable to the fuselage and operatively connected to the first threaded element so as to, in use, rotationally vibrate about the first axis; and a plurality of threaded rollers, which are screwed on the first and second threaded elements; the rollers being rotatable about their respective second axes parallel to and separate from the first axis with respect to the first and second threaded elements; the rollers are also rotatable about the first axis with respect to the first threaded element and the second threaded element.