Rotatable end of dose feedback mechanism

Abstract

An injection device for injecting a medicament includes a housing, a dose setting member (20) movable to set a dose to be injected, and a signal part (7). The signal part rotates from a first rotational position to a second rotational position to increase loading on a spring or spring arm when a dose is set due to rotation of the dose setting member. An internal pressure builds up in the injection device during injection which results in the signal part being captured in the second rotational position between first and second internal parts of the injection device. After the internal pressure dissipates by a sufficient amount during injection, the signal part rotates under the urging of the loaded spring from the second rotational position back to the first rotational position. A portion of the signal part moves into contact with a surface when the signal part reaches the first rotational position to produce tactile or audible feedback indicating that an end of dose condition has been reached.