US Patent 7921744 Rolling screw

Rolling screw (1) comprising a first threaded male member (6), a second threaded member (3), means (5) that permit said second threaded member (3) to rotate freely in relation to the housing (2), as well as means (7) that permit to maintain fixed and constant the position of the axis of said first threaded member (6) in relation to the housing (2). Means of synchronization are also foreseen for the relative rotation between said first member (6) and said second member (3). Said screw is characterized in that at least one of the two threaded members presents a threading conformation such to permit the transmission of the rotation motion to another element without relative tangential sliding action.