Mechanism for transmitting power of rotation

A rotary power transmission mechanism comprising:

• a link extending along a closed loop and consisting of a succession of portions, each of which has a longitudinal direction tangent to the closed loop;
• a first and second rotary element, mobile in rotation respectively around a first and second axis;
• link guide means designed to guide the link along a first drive circle coaxial to the first axis and along a second drive circle coaxial to the second axis, the closed loop comprising an active portion of each of the drive circles;
• and
• means for temporarily unifying each link portion to successively each of the rotating elements whenever the link portion passes into the corresponding active portion;
• wherein the temporary unification means comprise a plurality of self-locking means distributed at least along the active portion of the first drive circle, the self-locking means comprising at least a locking element simultaneously resting upon, on the one hand, a first support surface belonging to the first rotating element, and, on the other hand, upon a second support surface belonging to a link portion facing the locking element, wherein the first and second support surfaces are arranged in such a way that at least one locking element of the active portion of the first drive circle is jammed between the first and second support surface and is able to self-unlock whenever the corresponding self-locking means leaves the active portion, and wherein at least one of said first or second support surfaces is a tangential gripping surface that is parallel to the longitudinal direction of the link portion against which the locking element rests.