Clamp device with self-clamping jaws, in particular for a hydraulic linear winch

This clamping unit (1) comprises a body (2) having an elongated passage (3) for an object (4) to be clamped, with two mutually opposite, inclined surfaces (3a and 3b), a pair of jaws (5a and 5b), wedge-shaped, which are mounted so as to be able to move in the said passage between a first position, in which the jaws clamp the said object, and a second position, in which they release the object, two sets of rollers (6a and 6b) forming running paths for the associated jaws, the rollers (6a or 6b) of each set being supported and rotationally mounted in a mounting frame (7a or 7b) which can slide relative to the corresponding jaw and to the said body, and a pressure spring (16) placed in between each jaw (5a or 5b) and the frame (7a or 7b) of the set of rollers (6a or 6b) associated therewith, each spring bearing on one side against the associated jaw in order to stress it towards its first position and, on the opposite side, against an opposing bearing surface (18) provided at one end of the said frame in order to push the latter back into contact with a stop (25) provided on the said body (2).