A fluid cushioning apparatus acting as a pivoting medium of two objects having a pivoting feature includes a sleeve, a shaft and a partitioning piece. The shaft has two radially enlarged annulations being closely and rotatably mounted in the sleeve and a dividing wall being axially and radially extended between the two annulations to closely engage with the interior wall of the sleeve. The sleeve is mounted on a first object and the shaft is mounted on a second object which is always to have a pivoting relationship with the first object. The partitioning piece is capable of being closely fitted among the sleeve, the shaft and the two annulations and is secured on the sleeve so that the space formed between the shaft and the sleeve is divided into two compartments. The shaft is a hollow member one end of which is mounted a replenishing cushioning fluid supplier while the other end of which is mounted a check valve and a first hole is provided on the shaft so that the liquid supplier will supply the space with new cushioning fluid through the check valve and the first hole when there is a fluid loss in the space. The shaft is further provided with a second hole to let the fluid contained in one of the two compartments flow through the first and second holes to the other one compartment when the first and second object are in relative pivoting movement to obtain a neat cushioning effect.
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.
A prosthetic device is described which is arthroscopically implantable into a joint, which can restore function to a diseased joint, alleviating the need for joint therapy. The device has a ring or a pair of rings sized and shaped to fit within the joint. The ring or rings are comprised of a polymeric substance and may contain one or more compartments which are inflatable or expandable with air, a liquid or a semi-solid, through an arthroscope coupling means.
A prosthetic insert unit for cushioning shocks in prosthetics is provided. The unit includes attachment member (150 etc.), a lower sleeve (124' etc), a slide bearing (152' etc.) to allow free reciprocal motion therebetween, an elastomeric energy storage member (124' etc.) received in the interior of the sleeve (124' etc.), a piston (134' etc.) cooperative with said elastomer member to compress same, and an anti-rotation mechanism. Preferably, the anti-rotation mechanism is integral with the slide bearing (152' etc.). The elastomer member provides controlled deflection as well as damping for the insert. Preferably, an anti-click element (269 etc.) is provide to minimize rebound clicking. Acoustical elements (268 etc.) may also be included to minimize noise transmission into other areas of the insert.
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 operating chamber which receives a piston mounted on a tubular piston rod. The housing and operating chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channels and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a preferably sealed gas pressurized flexible bladder which forms an oil accumulator during inward movement of the piston rod into a displacement chamber and also produces variable forces for moving the piston rod outwardly to its extended position. An annular seal engages an inner portion of the piston rod and prevents the continuous higher hydraulic static pressure in the displacement chamber from transferring to the operating chamber and the annular seal between the housing and the outer portion of the piston rod.
A torsional vibration damper having a stator and a rotor provided with stator vanes and rotor wanes, respectively, which are arranged so as to form a plurality of work chambers fillable with damping medium and alternately changing their volumes during oscillation of the rotor. A damping device is provided in the rotor and has a compensation space in flow communication with the work chambers. The damping device has a throttle point configured so as to allow the compensation space to be pressurized by a relatively low pressure.
