Patent attributes
The present disclosure is directed to a spring arrangement for use in a drug delivery device and a drug delivery device including such a spring arrangement. The spring arrangement includes a clutch spring which is located axially interposed between a stationary housing component and an axially movable sleeve. The sleeve includes clutch features adapted to engage corresponding clutch features of a clutch element. The clutch spring biases the clutch features and the corresponding clutch features into engagement. The sleeve is coupled to a button such that upon actuation of the button the sleeve is translated against the bias of the clutch spring from a proximal position in which the sleeve is rotationally locked to the housing component into a distal position in which the sleeve is rotationally un-locked from the housing component. Upon release of the button the clutch spring translates the sleeve and the button into the proximal position.
