Anti-vibratory device with rotary compensation weights

An antivibration device of the type comprising at least two sets (2, 3) each comprising two identical rotors (4, 5;

• 6, 7) having respective eccentric flyweights (4A, 5A;
• 6A, 7A), said sets being disposed symmetrically about an axis of symmetry, and the axes of rotation of said rotors being parallel to one another and orthogonal to said axis of symmetry, and a drive system (8) for setting said rotors into rotation,
• the device being characterized:
• in that it comprises controllable moving equipment (11) carrying said drive system (8) and capable of sliding along said axis of symmetry to vary the phase offset between the eccentric flyweight rotors of the sets;
• and
• in that said drive system (8) comprises a single motor (12) for rotating said rotors, having its axis disposed perpendicularly to said axis of symmetry, and driving an endless connection passing around said rotors (4, 5;
• 6, 7) so that the lengths of the strands of the connection passing through said sets are equal.