| 摘要 |
According to one aspect, a drive assembly for a drug delivery device is provided for. The drive assembly may comprise a housing (10A, 10B, 10C) having a proximal end (100P) and a distal end (100D), a piston rod (20) being axially displaceable and rotatable with respect to the housing (10A, 10B, 10C) between a first angular position and a second angular position, a drive member (30) being axially displaceable, and a rotational bias member (50) being operable to transfer a resilient bias to the piston rod (20). The drive assembly may be configured such that, for setting a dose, the drive member (30) is proximally axially displaceable with respect to the housing (10A, 10B, 10C) and the piston rod (20) from a rest position to a dose set position. When setting the dose, the piston rod (20) may be rotated in a first rotational direction and, subsequent to the rotation in the first rotational direction, rotated in a second rotational direction with respect to the housing and the drive member. For setting the dose, the drive member (30) may interact with the piston rod (20) to convert proximal axial movement of the drive member (30) with respect to the housing (10A, 10B, 10C) into rotational movement of the piston rod (20) in the first rotational direction towards the second angular position against the resilient bias and the rotational bias member (50) may interact with the piston rod (20) such that the piston rod (20) is rotated in the second rotational direction towards the first angular position with respect to the drive member (30) and the housing (10A, 10B, 10C) by means of the resilient bias. Further, a piston rod (20) and a use of a spring (80) are provided for. |
