The A hand-held power tool includes a tool holder 2 for holding a tool and a pneumatic striking mechanism for periodically generating impacts on the tool held in the tool holder. The striking mechanism includes a guiding tube, an exciter piston, a striker, a pneumatic chamber closed by the exciter piston and the striker in the guiding tube, and a compensating opening in the guiding tube for ventilating the pneumatic chamber. A cap covers the compensating opening on an outside of the guiding tube. The cap is open in an opening direction which is largely tangential to the guiding tube.

A percussion tool including a parking assembly movable relative to a spindle. The parking assembly includes a seat coupled to the spindle, a first shuttle portion movable relative to an outer surface of the spindle, a biasing member positioned between the seat and the first shuttle portion, a second shuttle portion movable relative to the outer surface of the spindle, a bushing positioned within the spindle and configured to receive a portion of an anvil, and a fastener that couples the second shuttle portion to the bushing. The first shuttle portion and the second shuttle portion are movable together between a working position, in which a plurality of radial air vents in the spindle is closed, and an idle position, in which the plurality of radial air vents is open. The biasing member is configured to bias the first shuttle portion and the second shuttle portion into the idle position.

The invention relates to a striking hand-held machine tool having a tool holder for holding a striking tool on a working shaft, an electric motor, and a striking mechanism. In the striking direction, the striking mechanism has an exciter piston, a pneumatic chamber, a striker, an intermediate chamber and a rivet snap following one another. A closed channel connects a first channel opening in the pneumatic chamber and a second channel opening in the intermediate chamber. A non-return valve, which shuts off during an air flow from the first channel opening to the second channel opening and opens during an air flow from the second channel opening to the first channel opening, is arranged in the channel. Arranged on the second channel opening is a shut-off valve, which is forced into a position closing the second channel opening when the rivet snap is in the working position.

A rotary hammer includes a motor, a spindle coupled to the motor for receiving torque from the motor, a piston at least partially received within the spindle for reciprocation therein, a striker received within the spindle for reciprocation in response to reciprocation of the piston, and an anvil received within the spindle and positioned between the striker and a tool bit. The anvil imparts axial impacts to the tool bit in response to reciprocation of the striker. The rotary hammer also includes a synchronizing assembly operable in a first configuration in which the motor is drivably coupled to the piston for reciprocating the piston, and a second configuration in which the piston is decoupled from the motor. The rotary hammer further includes an actuator operable for switching the synchronizing assembly from the second configuration to the first configuration in response to depressing the tool bit against a workpiece.

A percussion mechanism contains a guide tube, an exciter piston, a hammer, a pneumatic chamber for coupling the hammer to the motion of the exciter piston, a striker, and a seat for the striker. The hammer has a striking point, defined by a striking surface of the striker when the striker lies against the seat. A check valve has an outlet opening and a closing mechanism for closing the check valve against an air flow from the interior of the guide tube. The outlet opening is arranged in such a way that the outlet opening is closed by the hammer during striking operation and otherwise is open.

A hand-held tool has a tool holder for holding a striking tool on a working axis, an electric motor, and a striking mechanism. The striking mechanism has an exciter piston moved by the motor, a striker coupled to the exciter piston by a pneumatic chamber arranged between the exciter piston and the striker, and a ram arranged in the striking direction of the striker piston. In a working position the ram rests counter to the striking direction against a stop. A stationary shut-off valve has a valve seat and an elastic shut-off member, wherein the elastic shut-off member in a relaxed state has a basic form which lifts from the valve seat, and wherein in the working position the elastic shut-off member is forced by the ram into a tensioned form resting against the valve seat.

A hand-held machine tool including a tool holder for a striking tool has a motor, an impact mechanism, a spool valve, and a pneumatic chamber. The impact mechanism has an exciter piston moved by the motor, and a hammer coupled to the exciter piston via a pneumatic chamber arranged between the exciter piston and the hammer, and a striker arranged in front of the hammer in the striking direction. In a working position counter to the striking direction, the striker bears on a stop, in a starting position the striker is offset in the striking direction relative to the working position, and in a rest position the striker is offset in the striking direction relative to the starting position. In the starting position, the hammer bearing on the striker closes the spool valve and, in the rest position, the hammer bearing on the striker opens the spool valve.

A machine tool and control method are disclosed. The machine tool has a tool receptacle which supports a chiseling tool so that it is movable along an axis of movement. A magneto-pneumatic striking mechanism has a primary drive, which is arranged around the axis of movement, and has a first magnetic coil and a second magnetic coil. On the axis of movement within the magnetic coils, the striking mechanism has a striker and riveting head. Furthermore, the striking mechanism has a pneumatic spring which acts on the striker. The control method provides for a pressure sensor which measures the prevailing pressure in the pneumatic spring during a movement of the striker in the direction opposite the striking direction. A controller initiates an acceleration phase at the start of a drop in pressure in the pneumatic spring. The primary drive accelerates the striker in the striking direction during the acceleration phase.

Percussion unit, especially for a rotary hammer and/or percussion hammer, comprising a control unit which is designed for open-loop and/or closed loop control of a pneumatic percussion mechanism, and at least one operating condition sensor unit. According to the disclosure, the control unit is designed to detect at least one percussion mechanism parameter depending on measurement values of the operating condition sensor unit.

A production method provides for punching holes in a metal strip, cold-forming the metal strip to form a guide tube, and joining the lengthwise edges of the metal strip to each other by a seam or teeth so as to create a uniform material. Subsequently, a piston-like striker is inserted into the guide tube.