Abstract: A tuned absorber for torsional vibrations with hydrostatic damping comprises relatively rotatable outer and inner members defining primary chambers therebetween, a damping liquid in the primary chambers, springs or gas cushions arranged in secondary chambers to exert no torque on the outer and inner members, and connections between the chambers for permitting liquid to flow from the primary chambers to the secondary chambers for applying liquid pressure to the springs or gas cushions in the secondary chambers.

Abstract: A central portion includes an inner member. An outer member defines together with said inner member first and second chambers adapted to contain a liquid, and gap means through which said first and second chambers communicate with each other. A reservoir is contained in said central portion and adapted to contain liquid. Passage means connect said reservoir to at least part of said chambers and are adapted to conduct liquid from said reservoir to said chambers and from said chambers to said reservoir. Movable members are disposed in said passages and arranged to present a lower resistance to the flow of liquid from said reservoir to said chambers than to the flow of liquid from said chambers to said reservoir. Said inner and outer members are angularly movable relative to each other and arranged to displace liquid between said first and second chambers through said gap means during such angular movement so as to perform a torsional damping action.

Abstract: An elastic coupling for transmitting torque from a driving shaft to a driven shaft and for damping torsional vibrations comprises packets of flexible leaf springs locked between a hub connected to one shaft and a clamping ring concentric with the hub. The hub and clamping ring define an annular chamber filled with a damping fluid. The packets of leaf springs extend radially and have outer leaf springs having a transverse cross section which tapers inwardly from an outer to an inner end. The outer leaf springs are so dimensioned that their maximum flexure is at least equal to the difference between the thicknesses of the outer and inner leaf spring ends.