Mechanical-hydraulic damper for a load subject to shocks and vibrations

A mechanical-hydraulic damper for a load which is subject to shocks and vibrations, comprising a co-operating pair of elements including a ball or roller screw and a nut, a first element of said pair of elements being mounted in a body for relative axial movement in relation to said body and the second element of said pair of elements being rotatably mounted in said body and so coupled to said first element that relative axial movement of said first element causes rotation of said second element, with said second element being coupled to hydraulic means which resist sudden or rapid rotation of said second element including drive means comprising a reversible pump to cause flow of hydraulic fluid around a closed hydraulic circuit mounted on said body, the rate of flow of fluid being restricted by a calibrated orifice comprising a reversible symmetrical control valve in communication with a reservoir of hydraulic fluid, the outlet of which is coupled to a fluid inlet at the middle of said symmetrical control valve, whereby the mechanical-hydraulic damper functions to damp successive shocks and vibrations in the same or reverse directions.