1. A drive mechanism for a drug supply device (1), comprising: a body (13, 17, 40) having a proximal end and a distal end, a rotation member (21) rotatably in a first direction relative to the body during setting the dose of the drug (5) and with the possibility of rotation in the second direction relative to the housing during dose delivery, the second direction being opposite to the first direction, the piston rod (12) configured to move in the distal direction of the relative but the dose supply housing is a drive element (20) that follows the rotational movement of the rotation element in the second direction during the dose delivery, and is the stop element (26) preventing the rotational movement of the drive element relative to the housing in the first direction during dose setting in which - the rotational movement of the drive element in the second direction is converted to the displacement of the piston rod in the distal direction relative to the housing. 2. The drive mechanism according to claim 1, in which the drive mechanism comprises a metering element (16, 34, 41) that can move relative to the housing (13, 17, 40) during installation and delivery of the dose and in which the movement of the metering element relative to the housing is converted into rotational movement of the rotation element relative to the housing. 3. The drive mechanism according to claim 2, in which the dosing element (16, 34, 41) is mounted, preventing its rotational movement relative to the housing (13, 17, 40). 4. The drive mechanism, according to any one of the preceding paragraphs, in which the drive element (20) and the rotation element (21) can rotate around a common axis of rotation. Mechanism1. Механизм привода для устройства (1) подачи лекарственного средства, содержащий:- корпус (13, 17, 40), имеющий проксимальный конец и дистальный конец,- элемент (21) вращения, выполненный с возможностью вращения в первом направлении относительно корпуса во время установки дозы лекарств
