The disclosure relates to a drug delivery device for expelling a pre-determined or pre-settable amount of a liquid medicament formulation which improves the stalling behavior and indicates the stalling state to the user. The device comprises: a medicament reservoir attached to a housing (10) and an expelling mechanism configured for acting against the medicament reservoir in order to expel a portion of the liquid medicament formulation therefrom, the expelling mechanism comprising -an arrangement of a threaded nut (12) in a fixed axial relation to the housing (10) and a lead screw (30) in threaded engagement with the threaded nut (12), the threaded nut (12) and the lead screw (30) being rotatable relative to each other by a rotational input interface (35), -a mechanical energy reservoir (60, 90) for storing energy, the stored energy being releasable from the energy reservoir (60, 90) by a rotational interface (61), -a drive train (40) having an upstream interface (42) coupled to the rotational interface (61) of the energy reservoir (60, 90) for feeding rotational energy into the drive train (40) and a downstream interface (49,49b) coupled to the rotational input interface (35) of the arrangement of the threaded nut (12) and the lead screw (30) for outputting rotational energy thereto to thereby rotate the lead screw (30) and the threaded nut (12) relative to each other, the drive train (40) further being equipped with a releasable latch (14, 151, 41) for preventing transfer of rotational energy from the upstream interface (42) to the downstream interface (49, 49b) when actuated and for allowing transfer of rotational energy from the upstream interface (42) to the downstream interface(49) when released； and -a trigger (70) movable relative to the housing (10) from a first position to a second position, the trigger (70) being connected to the releasable latch (14, 151, 41) for operating the releasable latch (14, 151, 41), the trigger (70) further being biased towards
