The fluid damper device includes a rotor inserted into a case, and a cover fixed to an opening portion of the case. A thin portion is formed at an end portion of the case on one side in an axis direction, and a contact portion which is in contact with a small-diameter portion of the cover in the axis direction is formed at four positions of an inner circumferential surface of the thin portion at equal angular intervals. A partitioning convex portion which partitions a damper chamber in a circumferential direction is formed on an inner circumferential surface of the case, and the contact portions are formed at positions corresponding to the partitioning convex portion in the circumferential direction. A concave portion recessed radially outward is formed at a position different from the contact portion in the circumferential direction, and a welding convex portion is formed in the concave portion.

A speed retarding device for a rotary nozzle includes a hollow cylindrical housing and a rotatable tubular shaft rotatably carried by the housing. The shaft has a central axial bore and an enlarged drag sleeve portion carried in the housing. A pair of support bearings support the drag sleeve portion of the shaft in the housing. An annular inner seal between each of the support bearings and the drag sleeve portion defines a cavity within the housing receiving a viscous fluid confined within the cavity. The drag sleeve portion includes a peripheral helical groove and a plurality of axial bores extending therethrough parallel to the central bore, one or more blind axial bores each having a closed end an open end, and a piston disposed in each of the one or more blind axial bores each defining an air space between the closed end and the piston.

A rotary damper having a simple self-standing mechanism which does not cause an inconvenience such as bounce of an opening/closing member at an end of an opening operation of the opening/closing member such as toilet lid is provided. A rotary damper has a housing, a shaft, a vane, a sliding member, an O ring, and a cap as main components. A shaft portion, formed in a pressure chamber of the housing, includes a blade portion protruding in an axial direction of the shaft portion. A cutout portion is formed in a center portion between both ends of the blade portion. On another side surface of the blade portion, a first groove is formed in a circumferential direction from a base of the blade portion to the outer periphery of the shaft portion. A second groove is formed on the outer periphery of the shaft portion spaced from the first groove.

A shock absorbing equipment having shear-wall-like mechanism with enhanced damping force for a building includes a longitudinal transmission rod, an upper dampers, and a lower dampers. The two upper dampers are mounted on the upper half wall. Two ends of each of the upper dampers is connected to the upper end of the longitudinal transmission rod and the upper half wall. The two lower dampers are mounted on the lower half wall. Two ends of each of the lower dampers is connected to the lower end of the longitudinal transmission rod and the lower half wall. The shock absorbing equipment sensitively amplifies a displacement between the floors caused by earthquake, so as to early dissipate seismic energy. Moreover, the needed number of the shock absorbing equipment for the building can also be reduced and impact on traffic flow and ambient lighting in the building can be reduced.

A torque absorber is described for absorbing a rotational torque that occurs when tubular elements are screwed together, the torque absorber comprising at least one cylinder and at least one piston movably arranged in the cylinder. The at least one cylinder is curved in the longitudinal direction of the cylinder and the at least one piston has a corresponding curved shape, such that the at least one piston can be moved into and out of the at least one cylinder. There is also described an apparatus comprising one or more torque absorbers for absorbing a rotational torque that occurs between two parts in the apparatus on the screwing together of tubular elements.

A torque absorber is described for absorbing a rotational torque that occurs when tubular elements are screwed together, the torque absorber comprising at least one cylinder and at least one piston movably arranged in the cylinder. The at least one cylinder is curved in the longitudinal direction of the cylinder and the at least one piston has a corresponding curved shape, such that the at least one piston can be moved into and out of the at least one cylinder. There is also described an apparatus comprising one or more torque absorbers for absorbing a rotational torque that occurs between two parts in the apparatus on the screwing together of tubular elements.

A vibration damping device which is able to damp vibration of a rotating body in a high-speed range and to certainly accelerate the rotating body to the high-speed range is provided.

A vibration damping device 1 damping vibration of a rotating body 100 includes an automatic balancer 2 which is configured to cancel out imbalance of the rotating body 100 when the rotating body rotates 100; a liquid damper 4 which is coaxially rotatable with the rotating body 100 and includes a collision member 23 provided in a casing 20 in which liquid 22 is sealed, the liquid colliding with the collision member 23 when the liquid 22 moves in a circumferential direction; and a relative rotation unit 5 which is configured to cause the liquid damper 4 to rotate relative to the rotating body 100.

Provided is a rotary damper on which the timing for generating a damping torque can be set freely. Groove-like bypass passages (805) that are longer in the circumferential direction than vanes (501) are formed in the upper surface (803) of a torque regulation plate (8) arranged on the bottom part (201) of a cylindrical circular chamber (200). When the rotor (5) rotates in a first rotational direction R1, if both end faces (508a, 508b) of the vanes (501) are positioned within a range of the respective bypass passages (805), each area (218) and the corresponding area (217) are communicated via the corresponding bypass passage (805), enabling movement of a viscous fluid (6) from the area (217) to the area (218). Subsequently, if the rotor (5) rotates further in the first rotational direction R1 and one or both of the end faces (508a, 508b) of each vane (501) is outside of the range of the corresponding bypass passage (805), each area (218) and the corresponding area (217) are not communicated via the corresponding bypass passage (805), and the viscous fluid (6) is unable to move from each area (217) to the corresponding area (218).

Provided is a rotary damper on which the timing for generating a damping torque can be set freely. Groove-like bypass passages (805) that are longer in the circumferential direction than vanes (501) are formed in the upper surface (803) of a torque regulation plate (8) arranged on the bottom part (201) of a cylindrical circular chamber (200). When the rotor (5) rotates in a first rotational direction R1, if both end faces (508a, 508b) of the vanes (501) are positioned within a range of the respective bypass passages (805), each area (218) and the corresponding area (217) are communicated via the corresponding bypass passage (805), enabling movement of a viscous fluid (6) from the area (217) to the area (218). Subsequently, if the rotor (5) rotates further in the first rotational direction R1 and one or both of the end faces (508a, 508b) of each vane (501) is outside of the range of the corresponding bypass passage (805), each area (218) and the corresponding area (217) are not communicated via the corresponding bypass passage (805), and the viscous fluid (6) is unable to move from each area (217) to the corresponding area (218).

Provided are a volume change compensation device capable of reducing a manufacturing burden with a simple configuration and a damper device including the volume change compensation device. A damper device 100 includes a rotary damper, and includes a volume change compensation device 140 in a shaft 121 of a rotor 120. The volume change compensation device 140 includes an inner cylinder piston 142 pressed by an inner cylinder piston pressing elastic body 145 in a body tube 141 communicating with a hydraulic fluid housing portion 103 of the damper device 100 through a connection path 141a. The inner cylinder piston 142 is formed in a bottomed cylindrical shape opening on a connection path 141a side. In the inner cylinder piston 142, an inner cylinder inner small piston 143 is pressed against a bottom portion 142b by a small piston pressing elastic body 144. An air hole 142c is formed at the bottom portion 142b of the inner cylinder piston 142. The inner cylinder inner small piston 143 slides in the inner cylinder piston 142 according to the amount of hydraulic fluid 150 in the inner cylinder piston 142.