An impact mechanism for use in a power tool having a motor and adapted to impart axial impacts to a tool bit. The impact mechanism includes a piston configured to reciprocate in response to receiving torque from the motor, a striker that is selectively reciprocable within the spindle in response to reciprocation of the piston, and an anvil that is impacted by the striker when the striker reciprocates towards the tool bit. The anvil imparts axial impacts to the tool bit. The striker includes a body portion formed of a first material and an insert portion within the body portion. The insert portion is formed of a second material that is more dense than the first material.

A percussion unit for a rotary hammer and/or percussion hammer includes a control unit that is configured for open-loop and/or closed loop control of a pneumatic percussion mechanism. In at least one operating state in which the control unit changes from an idle mode to a percussion mode, the control unit is configured to adjust at least one operating parameter temporarily to a starting value.

The control method for a hammer drill (1) provides the following steps. During basic operation, the motor (5) rotates at an operating speed for the drilling operation with chiseling action in order to rotationally drive the tool holder (2) and to drive the hammer mechanism (6) with a nominal striking power. The torque coupling (21) is monitored with the aid of a sensor (26). If a disengagement of the torque coupling (21) occurs, the striking power of the hammer mechanism (6) is reduced to below 10% of the nominal striking power during a disengagement of the torque coupling (21), and the torque coupling (21) is driven. When the disengagement of the torque coupling (21) ends, the striking power of the hammer mechanism (6) is increased to the nominal striking power and the torque coupling (21) is driven at the operating speed for the drilling operation with chiseling action.

A portable power tool has a tool holder 2, a motor 8 and an electro-pneumatic striking mechanism 4. The striking mechanism includes an excitation piston 13, a striker 14, a pneumatic chamber 18 for coupling the striker 14 to the excitation piston 13 and an anvil 15 which is arranged in the striking direction 5 downstream of the striker 14 and is provided for transmitting a blow of the striker to the tool. The anvil is hollow. The hollow interior space 23 is closed in the striking direction 5 and counter to the striking direction 5.

The present invention provides an electric working machine in which a control board can be disposed without limitations based on a length of a brushless motor in a direction along an axial line. The electric working machine comprises: a brushless motor provided with a rotor and a stator; a motor case and a motor housing in which the brushless motor is stored; a control board which is provided outside of the motor housing in a radial direction of an axial line defined at the center of the rotor, and supports the switching elements; a connection board which is provided in the motor case, and supports the sensors; a through hole provided on the motor case; a through hole provided on the motor housing; and leads and signal lines extending from inside of the motor housing to the outside of the motor housing through the holes.

An electropneumatic impact mechanism for an electric hand-held power tool, in particular a hammer drill and/or chipping hammer, wherein the impact mechanism has a transmission housing, a guide tube arranged at least partially in the transmission housing, an exciter piston that is movable in the axial direction in the guide tube, a connecting rod coupled to the exciter piston, and an eccentric wheel which is coupled to the connecting rod on one side and is mounted so as to be rotatable with respect to the transmission housing on the other side, wherein the impact mechanism has a bearing body on which the eccentric wheel is mounted rotatably by means of a pair of plain bearings.

Hand-held power tool having a tool fitting for holding a striking and rotating tool on a working axis, an electric motor, an impact mechanism, which has a striker moved periodically along the working axis, and having a rotary drive, which drives a spindle bearing the tool fitting in a rotating manner about the working axis, the rotary drive having a step-down eccentric gear mechanism, connected to the electric motor, and the spindle being coupled to the eccentric gear mechanism.

An impact tool includes a motor, a driving mechanism, a tool body, an elastically-connected part elastically connected to the tool body to be movable at least in a front-rear direction relative to the tool body, a detecting mechanism configured to detect pressing of a tool accessory against a workpiece, and a control part configured to control driving of the motor based on a detection result of the detecting mechanism. The detecting mechanism includes a movable member that is provided in one of the tool body and the elastically-connected part and configured to be moved by relative movement of the other of the tool body and the elastically-connected part in the front-rear direction, and a detector that is provided in the one of the tool body and the elastically-connected part and configured to detect rearward pressing of the tool accessory by detecting movement of the movable member.

A hammer drill is provided including a housing, a motor mounted within the housing, and a hammer mechanism. The hammer mechanism includes a crank plate or a wobble plate driven by the motor, a con rod coupled to the crank plate or the wobble plate, a piston reciprocatingly driven by the con rod along a longitudinal axis, a ram and a beat piece. At least one of the wobble plate or the con rod is made of sintered steel.

An impact tool includes a motor, a driving mechanism, a tool body, an elastically-connected part elastically connected to the tool body to be movable at least in a front-rear direction relative to the tool body, a detecting mechanism configured to detect pressing of a tool accessory against a workpiece, and a control part configured to control driving of the motor based on a detection result of the detecting mechanism. The detecting mechanism includes a movable member that is provided in one of the tool body and the elastically-connected part and configured to be moved by relative movement of the other of the tool body and the elastically-connected part in the front-rear direction, and a detector that is provided in the one of the tool body and the elastically-connected part and configured to detect rearward pressing of the tool accessory by detecting movement of the movable member.