Abstract: 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.

Abstract: 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.

Abstract: A control method for a percussive hand-held power tool (1) includes the steps: detecting a switching state of an operating button (12), detecting a temperature T using a temperature sensor (22), activating an electropneumatic striking mechanism (5) in response to an actuation of the operating button (12), an exciter (13) of the electropneumatic striking mechanism (5) being moved forward and backward along a working axis (3) at a repetition rate R, whereby a striker (14) coupled to the exciter (13) via a pneumatic chamber (16) is also moved. If the temperature T is greater than a limiting temperature Tc, the repetition rate R is continuously increased from idle up to a setpoint value (21). A duration until reaching the setpoint value (21) is less than 10 cycles. If the temperature T is less than the limiting temperature Tc, a duration until reaching the setpoint value (21) is greater than 200 cycles.

Abstract: The handheld power tool has a tool receptacle for accommodating a tool on a working axis (11) and an electric motor (5). A pneumatic percussion mechanism (6) has an exciter, which is moved back-and-forth by the motor (5) periodically in parallel to the working axis (11), a striker (14), which is movable on the working axis (11) and is coupled via a pneumatic spring (18) to the exciter, and an anvil (19), which is situated movably on the working axis (11) and is situated downstream from the striker (14) in the percussion direction (12). The anvil (19) has a cylindrical anvil section (22) having a diameter and multiple channels (30) extending over the entire length (31) of the anvil section (22). A cross-sectional area of the anvil section (22) is at most 5% less than a circular area defined by the diameter.

Abstract: 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.

Abstract: 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.

Abstract: The handheld power tool has a tool receptacle for accommodating a tool on a working axis (11) and an electric motor (5). A pneumatic percussion mechanism (6) has an exciter, which is moved back-and-forth by the motor (5) periodically in parallel to the working axis (11), a striker (14), which is movable on the working axis (11) and is coupled via a pneumatic spring (18) to the exciter, and an anvil (19), which is situated movably on the working axis (11) and is situated downstream from the striker (14) in the percussion direction (12). The anvil (19) has a cylindrical anvil section (22) having a diameter and multiple channels (30) extending over the entire length (31) of the anvil section (22). A cross-sectional area of the anvil section (22) is at most 5% less than a circular area defined by the diameter.

Abstract: A handheld machine tool is disclosed. The tool has a tool receiving area and a striking mechanism. The striking mechanism contains a striker, an exciter, and a pneumatic chamber. The striker strikes an intermediate striker at the strike point. The exciter is driven between a first dead center at a distance from the strike point and a second dead center in the vicinity of the strike point. A housing, which is encapsulated in an air-tight manner, has an interior which is closed by an exciter end face facing away from the striker. The interior is connected to the pneumatic chamber by a first valve which can be closed by the striker and by a second valve which can be closed by the exciter. The first valve is arranged in the vicinity of the strike point and the second valve is arranged in the vicinity of the first dead center.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism features: a flying mass, which is movable along an impact axis; an impact surface, which limits a movement of the flying mass along the impact axis in the impact direction; an exciting piston, which limits a movement of the flying mass along the impact axis opposite from the impact direction; a pneumatic chamber between the flying mass and exciting piston; a drive for periodically moving the exciting piston with a stroke along the impact axis, wherein the flying mass is excited to a periodic movement between the impact surface and exciting piston. The stroke is selected as a function of a maximum length of the pneumatic chamber such that the periodic movement of the flying mass on the path between an impact on the impact surface and a minimum approach of the exciting piston intermittently has a velocity of zero.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism includes: a flying mass; an impact surface which limits a movement of the flying mass along the impact axis in the impact direction; an exciting piston which limits a movement of the flying mass opposite from the impact direction; a pneumatic chamber between the flying mass and exciting piston; and a drive for periodically moving the exciting piston with a stroke along the impact axis.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism features: a flying mass, which is movable along an impact axis; an impact surface, which limits a movement of the flying mass along the impact axis in the impact direction; an exciting piston, which limits a movement of the flying mass along the impact axis opposite from the impact direction; a pneumatic chamber between the flying mass and exciting piston; and a drive for periodically moving the exciting piston with a stroke along the impact axis. The flying mass is excited to a periodic movement between the impact surface and a minimum approach of the exciting piston. A length ratio of the maximum length of the pneumatic chamber to the stroke is selected as less than 1.55.

Abstract: A hand-held machine tool includes a tool accept for mounting a chiseling tool on an operating axis. A pneumatic hammer mechanism includes an exciter, driven back and forth by a motor about a stroke between a dead point distant from the tool and a dead point near the tool, a hammer moved back and forth on the operating axis between a reversal point distant from the tool and a point of impact, and a pneumatic chamber sealed by the exciter and the hammer, which couples the movement of the hammer to the movement of the exciter. A damping device increases the pressure in the pneumatic chamber when the exciter during its motion in the direction to the dead point distant from the tool has approached to less than half the stroke to the dead point distant from the tool.

Abstract: A hand-held machine tool includes a tool accept for mounting a chiseling tool on an operating axis. A pneumatic hammer mechanism includes a hammer mobile on an operating axis, an exciter, and a pneumatic chamber sealed by an exciter and the hammer, which couples the movement of the exciter to the hammer. The exciter is driven by a motor and moves back and forth between a frontal dead point distant from the tool and a dead point near the tool. A damper device includes a supercharger and a controlled outlet valve. The controlled outlet valve allows air to flow from the supercharger into the pneumatic chamber when the exciter is in the proximity of the dead point distant from the tool.

Abstract: A hand-held power tool has a pneumatic striking mechanism (6). The striking mechanism (6) has a motor-driven exciter (12), a striker (13) and a pneumatic chamber (15) arranged along a working axis (10) between the exciter (12) and the striker (13). At least 20% of the volume of the pneumatic chamber (15) is filled with a monoatomic gas.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism features: a flying mass, which is movable along an impact axis; an impact surface, which limits a movement of the flying mass along the impact axis in the impact direction; a hammer piston, which limits a movement of the flying mass along the impact axis opposite from the impact direction; a pneumatic chamber between the flying mass and hammer piston; a drive for periodically moving the hammer piston with a stroke along the impact axis, wherein the flying mass is excited to a periodic movement between the impact surface and hammer piston. The stroke is selected as a function of a maximum length of the pneumatic chamber such that the periodic movement of the flying mass on the path between an impact on the impact surface and a minimum approach of the hammer piston intermittently has a velocity of zero.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism features: a flying mass, which is movable along an impact axis; an impact surface, which limits a movement of the flying mass along the impact axis in the impact direction; a hammer piston, which limits a movement of the flying mass along the impact axis opposite from the impact direction; a pneumatic chamber between the flying mass and hammer piston; and a drive for periodically moving the hammer piston with a stroke along the impact axis. The flying mass is excited to a periodic movement between the impact surface and a minimum approach of the hammer piston. A length ratio of the maximum length of the pneumatic chamber to the stroke is selected as less than 1.55.

Abstract: A pneumatic hammer mechanism is disclosed. The hammer mechanism includes: a flying mass; an impact surface which limits a movement of the flying mass along the impact axis in the impact direction; a hammer piston which limits a movement of the flying mass opposite from the impact direction; a pneumatic chamber between the flying mass and hammer piston; and a drive for periodically moving the hammer piston with a stroke along the impact axis.