Provided is a sound reduction or vibration damping apparatus that has a new sound control principle where the sound control principle is totally different from a known passive or active sound control apparatus. A sound reduction or vibration damping apparatus 1 includes a mass portion 11, spring portions 12a and 12b placed between the mass portion 11 and a structural member 13, and a control unit 4 for causing the spring constants of the spring portions 12a and 12b to continue changing. The sound reduction or vibration damping apparatus 1 is mounted on the structural member 13 to reduce sound passing through the structural member 13 or sound generated from the structural member, or damp the vibration of the structural member 13.

Provided is a sound reduction or vibration damping apparatus that has a new sound control principle where the sound control principle is totally different from a known passive or active sound control apparatus. A sound reduction or vibration damping apparatus 1 includes a mass portion 11, spring portions 12a and 12b placed between the mass portion 11 and a structural member 13, and a control unit 4 for causing the spring constants of the spring portions 12a and 12b to continue changing. The sound reduction or vibration damping apparatus 1 is mounted on the structural member 13 to reduce sound passing through the structural member 13 or sound generated from the structural member, or damp the vibration of the structural member 13.

The invention relates to an apparatus for mounting an object to a structure. The apparatus includes an elastic arrangement including at least two elastic partial arrangements. The two elastic partial arrangements are arranged at a distance in the direction of a main axis, and the two elastic partial arrangements are soft in the direction of the main axis and stiff in all directions orthogonal to the main axis. Each of the two elastic partial arrangements comprises an inner connection area close to the main axis and an outer connection area farther away from the main axis, and each of the two elastic partial arrangements comprises at least two leaf springs which extend between the inner connection area and the outer connection area and which are spirally wound into each other within a common leaf plane.

The invention relates to an apparatus for mounting an object to a structure. The apparatus includes an elastic arrangement including at least two elastic partial arrangements. The two elastic partial arrangements are arranged at a distance in the direction of a main axis, and the two elastic partial arrangements are soft in the direction of the main axis and stiff in all directions orthogonal to the main axis. Each of the two elastic partial arrangements comprises an inner connection area close to the main axis and an outer connection area farther away from the main axis, and each of the two elastic partial arrangements comprises at least two leaf springs which extend between the inner connection area and the outer connection area and which are spirally wound into each other within a common leaf plane.

A torsional damping device and methods are disclosed. The device has an inertial body, a housing, a biasing mechanism, and a damping element. The housing has a mounting surface for mounting to a structure experiencing a rotational force, the inertial body rotatably and removably coupled to the housing. The biasing mechanism is configured to bias the inertial body towards the neutral position. The damping element is configured to damp motion of the inertial body relative to the housing. The second position of the inertial body comprises a position wherein the inertial body is at least one of (a) in motion relative to the housing and (b) experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the damping element. The inertial body is configured to effectuate a counter-rotational force on the structure when the inertial body is in the second position.

A torsional damping device and methods are disclosed. The device has an inertial body, a housing, a biasing mechanism, and a damping element. The housing has a mounting surface for mounting to a structure experiencing a rotational force, the inertial body rotatably and removably coupled to the housing. The biasing mechanism is configured to bias the inertial body towards the neutral position. The damping element is configured to damp motion of the inertial body relative to the housing. The second position of the inertial body comprises a position wherein the inertial body is at least one of (a) in motion relative to the housing and (b) experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the damping element. The inertial body is configured to effectuate a counter-rotational force on the structure when the inertial body is in the second position.

The invention relates to a vibration damper (1) configured to be provided on a low frequency sound generator, which comprises a feeder unit (2) with a positive feedback system regulated by a reciprocating spring loaded piston (3) and a resonator tube (4). The vibration damper (1) may be positioned outside the resonator tube (4). The vibration damper (1) comprises a first flange (5) connected to the resonator tube (4), a number of springs (6), a second flange (7) and a number of weights (8).

The present disclosure relates to an inertia measurement module for an unmanned aircraft, which comprises a housing assembly, a sensing assembly and a vibration damper. The vibration damper comprises a first vibration-attenuation cushion; and the sensing assembly comprises a first circuit board, a second circuit board and a flexible signal line for connecting the first circuit board and the second circuit board. An inertia sensor is fixed on the second circuit board, and the first circuit board is fixed on the housing assembly. The inertia measurement module further comprises a weight block, and the second circuit board, the weight block, the first vibration-attenuation cushion and the first circuit board are bonded together. The present disclosure greatly reduces the influence of the operational vibration frequency of the unmanned aircraft on the inertia sensor and improves the measurement stability of the inertia sensor.

A vibration damper for reducing a vibration in a cable is provided. The vibration damper includes an attachment portion that is attached to the cable. The vibration damper includes a flexible leg portion attached to the attachment portion. The vibration damper includes a weighted portion attached to the flexible leg portion. The weighted portion is spaced a distance apart from the attachment portion.

A vibration damper for reducing a vibration in a cable is provided. The vibration damper includes an attachment portion that is attached to the cable. The vibration damper includes a flexible leg portion attached to the attachment portion. The vibration damper includes a weighted portion attached to the flexible leg portion. The weighted portion is spaced a distance apart from the attachment portion.