Abstract: A mechanism based on a reduction gear assembly which produces two torques of equal intensity, both counter-rotational, applied to rotating shafts which may or may not be positioned coaxially. This torque force is achieved without transmitting any torque to the supporting structure. The mechanism comprises two reduction gearboxes with planetary gear trains consisting of internal planet gear wheels linked to the counter-rotating input shafts, satellite gear wheels, freely rotating on their planet pinion cage which is connected to the counter-rotating output shafts, as well as external planet gear wheels interlocked and hence constrained to rotate in the same direction, thereby balancing the torques by reducing speed on one output shaft and accelerating speed on the other shaft.

Abstract: The device absorbs vibrations which occur in the strings of a sports racket in order to reduce the risks of articular damage to the player's elbow. It is comprised of an elastomer element (1) having an elongate shape and a small cross-section terminated by spherical protuberances (2) used to tie the element to the strings. The device is provided at its middle with a bulge (3) for centering transversely the device in the strings of the racket and having the function of stiffening the element while increasing locally its linear mass. The device is fixed in the strings by interlacing it by one turn on the bearing strings (4).