A device for acquiring a blood sample comprising a lancet, a puncture drive having a drive rod coupled on the lancet, and a compression spring, which propels it is disclosed. A flywheel mass, which is mounted as to make it movable, is coupled to the drive rod. The flywheel mass can absorb kinetic energy during a propulsion phase and cause retraction of the lancet after reaching a maximum piercing depth. The flywheel mass can be a flywheel connected via a connecting rod to the drive rod and is set into rotation during propulsion of the lancet. After overcoming a dead center defining the maximum piercing depth, rotational energy stored in the flywheel causes the retraction of the lancet. At a specific angle, the rotation of the flywheel is stopped and the residual piercing depth is defined.