A clutch mechanism for use in a rotary power tool having a motor comprises an input member to which torque from the motor is transferred and an output member movable between a first position in which the output member is engaged with the input member for co-rotation therewith, and a second position in which the output member is disengaged from the input member. The clutch mechanism further comprises a biasing member biasing the output member into the first position and an electromagnet which, when energized, moves the output member from the first position to the second position.

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.

There is disclosed an orthopaedic impactor, comprising: a strike assembly arranged to impart a force to an object; and a winding arranged to receive a current and thereby generate a magnetic field. The winding is arranged to interact with the strike assembly so that, in use, a magnetic field generated by the winding causes the strike assembly to move so as to impart the force to the object.

A tool includes a tool head with a utilization surface. The tool also includes a counter device responding to an impact applied to the utilization surface. The counter device has a memory, a microcontroller controlling operation of the counter device, an indicator, and an energizer connected to the microcontroller, which in response to the impact applied to the utilization surface, produces an electric current energizing the counter device to make a modification in the memory and provide information about the cumulative count of impacts in the memory via the indicator to a user.

A rotary hammer adapted to impart axial impacts to a tool bit. The rotary hammer includes a housing, a motor supported by the housing, a spindle coupled to the motor for receiving torque from the motor, causing the spindle to rotate, a reciprocation mechanism operable to create a variable pressure air spring within the spindle, an anvil received within the spindle for reciprocation in response to the pressure of the air spring, the anvil imparting axial impacts to the tool bit, a bit retention assembly for securing the tool bit to the spindle, and an electromagnetic clutch mechanism switchable between a first state, in which the reciprocation mechanism is enabled, such that the anvil imparts axial impacts to the tool bit, and a second state, in which the reciprocation mechanism is disabled, such that the anvil ceases to impart axial impacts to the tool bit.

A power tool (1) is provided, especially a hammer drill and/or a chiseling hammer drill, including a percussive mechanism (12) with a percussive element (13) to generate a percussive pulse onto a tool (1), the element being reversibly movable along a longitudinal axis (R) by a magnetic field in order to generate the percussive pulse, and including at least a first and a second coil device (1, 2) to generate the magnetic field. Each coil device (1, 2) has at least a first coil ring (3) with a first radius (R1) and a second coil ring (4) with a second radius (R2), whereby the first radius (R1) of the first coil ring (3) is greater than the second radius (R2) of the second coil ring (4), so that a space (S) is formed, at least in certain areas, between the at least first and second coil rings (3, 4), whereby a fluid (L), especially an air stream, that serves to cool the coil device (1, 2) can flow through the space.

A handheld power tool (1) is provided, including a tool holder (2) for receiving and locking a tool (3) on a working axis (4), and including a power tool housing (6). A striking mechanism (8) includes a striker (10) for applying impacts in the impact direction (9) and an anvil (11) for absorbing the impacts and for transmitting the impacts in the impact direction (9) onto the tool (3) accommodated in the tool holder (2). A collar (18) is fastened to the power tool housing (6) and to the anvil (11). When the anvil (11) abuts a rebound impact damper (13) in the impact direction (9), the elastic collar (18) applies a force acting in the impact direction (9) onto the anvil (11).

A handheld power tool includes a tool holder for holding a tool, an electric motor, a shaft connecting the tool holder and the electric motor, and a protective device for stopping the tool holder in an uncontrolled situation. The protective device includes a sensor for detecting the uncontrolled situation, a switchable current source and a normally closing magnetic brake. The switchable current source outputs a first current not equal to zero in response to signals of the sensor if an uncontrolled situation is not detected; the current source does not output a current or outputs a second current different from the first current if an uncontrolled situation is detected. The normally closing magnetic brake engages on the shaft and does not apply a torque to the shaft when energized by the first current. The normally closing magnetic brake applies a torque counteracting the rotational movement of the shaft when not energized or when energized by the second current.

An impact tool includes a motor, a driving mechanism, and a vibration sensor. The driving mechanism is configured to perform a hammering operation of linearly driving a tool accessory along an impact-axis by power of the motor. The impact-axis extends in a front-rear direction of the impact tool. The vibration sensor is configured to detect vibrations. The vibration sensor is disposed such that the vibration sensor is capable of detecting vibrations of a first frequency among vibrations caused in the impact tool, and such that transmission of vibrations of a second frequency to the vibration sensor is suppressed. The vibrations of the first frequency result from the hammering operation. The second frequency is different from the first frequency.

A hand-held power tool device, in particular a hammer drill and/or chisel hammer device, includes at least one operating element and at least one locking unit. The at least one locking unit includes at least one locking element and at least one controllable actuator element. The at least one locking element can be moved from at least one storage position into at least one locking position, and vice versa, and locks the operating element in at least one operating state in the locking position. The at least one controllable actuator element influences motion of the locking element.