The present impact absorbing member includes: a hat-shaped member having a hat top section; and a plate-shaped member facing the hat top section. A deformation guidance section is provided on a wall section of at least one of the hat top section and the plate-shaped member. The deformation guidance section includes: a first high strength section having relatively higher buckling resistance in the wall section; and a pair of low strength sections having relatively lower buckling resistance and arranged on both sides of the first high strength section therebetween in a view along the longitudinal direction. Furthermore, the impact absorbing member includes a pair of second high strength sections disposed on both sides of the deformation guidance section to be adjacent to the pair of low strength sections in a view along the longitudinal direction and having a higher buckling strength relative to the low strength sections.

Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may include a feedback loop that senses motion of an intermediate mass. In noisy environments, where the feedback loop would otherwise fail or provide inadequate isolation, feedforward control can be implemented to sense floor vibrations and reduce motion of the intermediate mass that would otherwise be induced by the floor vibrations. The feedforward control can reduce motion of the intermediate mass to a level that allows the feedback loop to operate satisfactorily.

An aluminum alloy according to the present invention includes 1.2% by mass to 4.0% by mass of copper, 4.0% by mass to 14.0% by mass of zinc, 0.5% by mass to 4.0% by mass of magnesium, 0.01% or less of silicon, and 0.01% or less of iron, with the balance containing aluminum and inevitable impurities, and has an average equivalent circle crystal grain size of 500 nm or less.

Various embodiments provide a bush for isolating vibrations, the bush comprising: a first anchor part defining a longitudinal axis; a second anchor part disposed coaxially with respect to the first anchor part; a first resilient body operably engaged with the first anchor part; a second resilient body operably engaged with the second anchor part; and an inertial mass element disposed between the first anchor part and the second anchor part. The inertial mass element is independently connected to the first resilient body and the second resilient body. Also, the first resilient body, second resilient body and inertial mass element are arranged to isolate vibrations between the first anchor part and the second anchor part within a predetermined operational frequency range. Further, the inertial mass element is arranged to isolate the first anchor part and second anchor part from dynamic stiffness increases associated with eigenmodes of the first resilient body and the second resilient body in the predetermined operational frequency range.

A dual rate jounce bumper and a vehicle containing the dual rate jounce bumper are useful.

A subsea tubular system comprises extended sections of a first material and interposed sections of a second, different material that aids in damping vibration resulting from subsea dynamic conditions such as current. The vibration damping sections may make up a portion of the overall system significantly less than the sections of the first material. The number, length, and positions of the vibration damping sections may be selected based on factors such as the diameter, overall length, profile, and so forth. The system may be used as a riser or other conduit for the production of minerals such as oil and gas.

The present disclosure provides a single-degree-of-freedom (SDOF) magnetic damping shock absorber based on an eddy current effect, comprising a lower plate, a ring-shaped magnet a, a ring-shaped magnet b, an aluminum cylinder, a bottom copper sheet, a copper sheet, a top copper sheet, a bearing seat, a linear bearing, a bearing end cap, a load, a piston shaft, a stepped shaft, a fixed collar, a coil spring, a lower clamping shaft, and fixing screws. When the shock absorber is working, the ring-shaped magnet a keeps stationary at the lower end and the ring-shaped magnet b reciprocates in the vertical direction. Both magnets are arranged in a mutual attraction manner. Under the action of a time-varying electromagnetic field generated by the relative movement of the ring-shaped magnet b, the copper sheet arranged between the two ring-shaped magnets generates eddy current damping. The movement of the ring-shaped magnet b is inhibited.

A hollow stabilizer includes a curved part having eight regions defined in a cross section. A first region includes a 90° first part when the center of the inside of the curve is taken to be at 0° and the center of the outside of the curve is taken to be at 180°. A third region includes a 0° third part. A fifth region includes a 270° fifth part. A seventh region includes a 180° seventh part. The radii of curvature of the respective outer surfaces of the third part and the seventh part are larger and the radii of curvature of the respective outer surfaces of the second part and the sixth part are smaller than the radii of curvature of the respective outer surfaces of the fourth part and the fifth part.

An antivibration unit attachment structure according to the present aspect includes: a vibration absorption part having a first elastic member which is elastically deformable in a first direction and which is connected to a vibration generation part; and a second elastic member which supports the vibration absorption part and which is connected to a vibration reception part. The second elastic member includes a movable part that extends from the vibration absorption part to both sides in a second direction and that is supported by the vibration reception part. The second elastic member is elastically deformable in the first direction and has an elastic coefficient different from that of the first elastic member. The vibration reception part includes a regulation member that comes into contact with at least one of the vibration absorption part and the second elastic member and that limits displacement of the second elastic member to the first direction.

A shaft coupling includes a drive hub that is coupled to a drive shaft to rotate integrally with the drive shaft, a driven hub that is coupled to a driven shaft to rotate integrally with the driven shaft, and a rotation transmission portion that transmits rotation between the drive hub and the driven hub. A dynamic vibration absorber is integrally coupled to a section of at least one of the drive hub and the driven hub. The section is an uninvolved section that is not involved in a torsional stiffness of the whole shaft coupling.