Trigger Mechanism and Drug Delivery Device herewith

A drug delivery device for selecting and dispensing a number of user variable doses of a medicament, the device comprising:

• a trigger mechanism comprising a trigger element configured to be moved in a first direction relative to a counter element, wherein the trigger element comprises a first interference member and the counter element comprises a second interference member which is located with respect to the first interference member such that upon movement of the trigger element relative to the counter element the first interference member contacts and passes over the second interference member, thereby generating an audible and/or tactile feedback,
• a housing,
• a dose selector operable to set a dose by rotation relative to the housing,
• a number sleeve arranged within the housing such that at least a portion of the number sleeve is visible through a first aperture in the housing,
• a piston rod coupled to the housing and to a drive sleeve such that rotation of the drive sleeve relative to the housing causes the piston rod to translate relative to the housing,
• a clutch arranged between the number sleeve and the drive sleeve,
• a dispense clicker comprising a flexible arm and a toothed profile, and
• a button operable to effect dose dispensing.