Hand-held power tool with air spring percussion mechanism, linear motor, and control process

A method of controlling a hand-held power tool including a striking piston (5) for applying blows to a working tool (7), a linear motor (2) for driving the striking piston (5) and including a rotor (3) displaceable axially along a percussion axis (A), and an air spring (4) located between the striking piston (5) and the rotor (3), the method comprising the steps of displacing the rotor (3), in a first operating state (17a) that corresponds to a stable percussion operation between a front, in an operational direction of the power tool, reversal point (W) located near the striking piston (5) and a rear reversal point (W) spaced from the front reversal point;

• displacing the rotor (3) toward the striking piston (5) in an operating state (17b) other than the first operating state (17a) and which includes a delay step (18) in which the rotor movement toward the striking piston (5) is delayed electromagnetically;
• and an energizing step (19) in which the computing means calculates, based on data of a kinematic reference movement state (S(x(t+Δt), v(t+Δt), a(t+Δt))) of the rotor at time (t+Δt), a necessary current to be supplied to a field coil (10) of the linear motor (2) in order to achieve a kinematic movement state corresponding to a kinematic reference movement state, and energizes the field coil (10) via a power electronics (33).