US Patent 11904448 Hand-held power tool

In a control method for a hand-held power tool, a striking mechanism is driven with an electric motor, wherein an exciter piston of the pneumatic striking mechanism is driven periodically by the electric motor and a striking piston of the striking mechanism is coupled to the exciter piston via a pneumatic chamber. The method includes detecting the acceleration of a machine housing along a striking direction of the striking piston in different phases of the movement of the exciter piston; and controlling a rotational speed of an electric motor according to the detected acceleration in the different phases.