Pyrotechnic driving device

A driving device, comprising a hand-held housing with a piston element arranged therein for the transmission of energy to a fastening element to be driven in a driving direction;

• a propellant charge;
• a combustion chamber, which is arranged between the propellant charge and the piston element and extends around a central axis;
• and, an actuator, by which the energy to be transmitted from the propellant charge to the piston element can be varied in such a way that the energy can be set, wherein the driving device has a number of venting channels connected to the combustion chamber that can be exposed by a movable slide of the actuator, wherein the number of venting channels respectively open out into the combustion chamber by a vent opening, which can be partially or completely covered by the slide, and wherein the number of venting channels have in each case a cross-sectional area of the vent opening which increases in the driving direction.