Abstract: A coupling-socket adapter assembly for a prosthetic limb. A base plate subassembly is attachable to a first prosthetic limb component. A coupling-socket adapter is rotatably attached to the base plate subassembly and has a cavity for receiving a male coupling member (such as a boss of a pyramidal link-plate). Various mechanisms, including a ring having internal threads and including a ring-clamp, are disclosed for locking the coupling-socket adapter against rotation with respect to the base plate subassembly and for unlocking the coupling-socket adapter for rotation with respect to the base plate subassembly, wherein the mechanisms are operable when the base plate subassembly is attached to the first prosthetic limb component.

Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical chamber which receives a piston mounted on a tubular piston rod. The housing and chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channel and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a gas filled flexible bladder which forms an oil accumulator during inward movement of the piston rod and also produces variable forces for moving the piston rod outwardly to its extended position. The housing confines a gap defining ring which compensates for changes in oil viscosity with heat.