Abstract: A mounting to hang an engine to a frame, adapted to insulate the frame from predetermined high-frequency and small-amplitude vibrations. The mounting comprises an envelope, a cover in the form of an elastomeric diaphragm associated with the side walls of the envelope, a pin adapted to receive the engine weight, engagement parts connecting the envelope to the frame. The mounting is comprised of a rocking system consisting of two masses and three elastomeric bodies with rigidities K2, K3, K4. The two masses are connected to each other by one elastomeric body and are in parallel to the elastomeric diaphragm being connected to the pin and envelope by interposition of the two other elastomeric bodies. The diaphragm and the parallel system when high-frequency and small-amplitude vibrations occur, give rise to a dynamic rigidity defined by two peaks and a valley therebetween; one of the peaks has a lower height than the other.

Abstract: A damping device which is disposed between an oscillating mass and a fixed structure. The device includes a rigid container, a first membrane forming the lid of the container, a low-viscosity liquid inside the container, an elastomeric diaphragm separating the space inside the container into two chambers, a second elastomeric membrane forming the base of the second chamber, and annular conduit with its two ends hydraulically connecting the first chamber to the second chamber for damping low frequency and high amplitude oscillations of the oscillating mass. The elastomeric diaphragm extends up to the annular damping conduit, and the diaphragm forms at least a portion of the conduit wall.

Abstract: A vibration isolation mount for elastic suspension of an automobile engine having a body containing a dampening liquid controlled so as to maximize the dampening of low frequency oscillations having a high amplitude and to minimize high frequency oscillations having a small amplitude. The flow of dampening liquid between two chambers is controlled by a pair of bell-shaped elements nested together to form a conduit therebetween. The bell-shaped elements can be rotated with respect to each other, preferably by an electric motor, to open and close perforations in the bell-shaped elements.