The actuation device (3) includes a slidable carrier member (23) being biased for sliding movement, and the movement of the slidable carrier member is damped by means of a piston assembly (25) arranged displaceably in a cylinder (26). The piston assembly (25) is biased towards a position at the second end (28) of the cylinder (26), the first end (27) of the cylinder (26) is at least substantially closed, and the piston assembly (25) and/or the cylinder (26) is adapted to provide a leak opening small enough in order to create a pressure reduction inside the cylinder (26) between the first end (27) of the cylinder (26) and the piston assembly (25) when the piston assembly travels in the direction against the second end (28) of the cylinder (26).