Active hydraulic anti-vibration support and active antivibration system incorporating said support

Active hydraulic anti-vibration support designed to be interposed between two rigid elements and comprising:

• first and second rigid armatures intended to be fixed respectively to the two rigid elements to be connected,
• an elastomer body linking the two armatures to one another and partially bounding a working chamber filled with liquid,
• a flexible wall partially bounding a compensating chamber filled with liquid, which is connected to the working chamber by a throttled passage also filled with liquid,
• an exciter member having a first face communicating with the liquid contained in the working chamber and a second opposing face isolated from said working chamber, said exciter member being movably mounted in a direction of displacement substantially perpendicular to the first and second faces of the exciter member, starting from a non-operating position,
• a control device designed to displace the exciter member at least in a first direction in said direction of displacement into an end stop position,
• an elastic return device permanently applying a force to the exciter member to return it to its non-operating position, in accordance with a certain elasticity curve which imparts said return force depending on the displacement undergone by this exciter member parallel with the direction of displacement, this curve having a tangent for a first displacement value corresponding to the non-operating position of the exciter member, and the return force having a certain threshold value for a second displacement value corresponding to the end stop position of the exciter member, wherein the elasticity curve of the return device is non linear and is located below said tangent at least in the vicinity of the second displacement value.