from the pump volume 27 into the pressure chamber 4 the thermal losses appearing during the compression can be kept small in this way the outlet valve 44 closes as soon as the pump piston 22 moves back to the basic position the user can actuate the triggering switch 9 so as to trigger the driving operation the control device 35 preferably first tests whether the pressure chamber 4 is loaded if the pressure chamber 4 is not loaded for example after a long inactivity of the driving device 1 the control device 35 loads the pressure chamber 4 the pressure chamber 4 is loaded with the complete sequence 36 of the current pulses 37 the control device 35 shortens the sequence 36 if the pressure chamber 4 is partially loaded for example the control device 35 determines by means of a pressure sensor the pressure in the pressure chamber 4 for each pressure a notation is made in a control table as to how many of the first current pulses 37 of the sequence 36 are to be skipped u2014 that is with which of the current pulses 37 of the sequence 36 one is to begin if the pressure chamber 4 is loaded the control device 35 opens the controllable valve 20 the air quantity under pressure in the pressure chamber 4 accelerates by means of the driving piston 14 the ram 3 after the driving operation the driving piston 14 is retrieved u2014 for example by means of a pump a spring a motor the user u2014 and the switchable valve 20 is closed the work volume 18 is preferably ventilated for the retrieval of the driving piston 14 the control device 35 loads the pressure chamber 4 by means of the sequence 36.