A percussion mechanism for a repetitively hammering hand power tool, whose striking frequency and striking intensity are controllable independently of one another, has a striker (2), movable axially forward and backward in a guide barrel (1), and a device (5) exerting pressure on the striker (2), as a result of which the striker can be set into a forward motion in the direction of a tool bit (4) that is insertable into the hand power tool. A blocking element (10) is also provided, with which the striker (2) is blockable in its forward motion, and the striking frequency of the striker (2) is adjustable by controlling the blocking time of the blocking element (10).

An object of the invention is to provide an improved technique for lessening an impact force caused by rebound of a tool bit after its striking movement in an impact power tool. The representative impact power tool comprises a tool body, a hammer actuating member, a tool holder, a driving mechanism, a weight placed in contact with the hammer actuating member to move rearward by a reaction force transmitted from the hammer actuating member when the hammer actuating member performs a hammering operation on the workpiece and an elastic element elastically deformed when the weight moves rearward in the tool body to push the elastic element such that the elastic element absorbs the reaction force transmitted to the weight. The weight is defined one or both of the cylinder and the tool holder.

A hand power tool has a housing, and drive motor accommodated in the housing, a tool receptacle in which a tool is guided, a gear mechanism, a driving gear, and rotary sleeve arranged so that via the gear mechanism, the driving gear, and the rotary sleeve the tool receptacle is drivable in rotation, a crank drive mechanism and a hammering mechanism located inside the rotary sleeve so that the tool receptacle is drivable through the crank drive mechanism and the hammering mechanism translationally, and a safety coupling provided between the driving gear wheel and the rotary sleeve and formed so that the safety coupling separates if a limit torque is exceeded, the safety coupling being formed as an overlock coupling seated on the rotary sleeve and having two axially adjacent coupling parts that mesh in a form-locked manner by torque-transmitting transmission elements and are overlockable if the limit torque is exceeded counter to an axially acting elastic force, one of the coupling parts being a part associated with the driving gear wheel and rotatable relative to the rotary sleeve while the other of the coupling parts is coupled to the rotary sleeve in a way that transmits torque.