A tool with two sequential gear trains and gear carrier assemblies adapted to be recessed into internal gears. The internal gear assembly also prevents rotation of the internal gear assembly relative to a housing of the tool. For example, the internal gear assembly can include a first gear train and second gear train sequentially coupled to the first gear train, wherein a first ring gear and first planet gears of the first gear train are substantially similar to a second ring gear and second planet gears of the second gear train.

A power tool includes a motor, a speed reducer and a speed-reducing-ratio change mechanism. The speed reducer includes planetary gear mechanisms arranged in multiple stages. The speed-reducing-ratio change mechanism is configured to change a speed reducing ratio of the speed reducer in response to a change of a rotating direction of a motor shaft. At least two stages of the planetary gear mechanisms are configured such that an internal gear in each stage selectively functions as a fixed element. The speed-reducing-ratio change mechanism includes a one-way clutch and a lock mechanism configured to non-rotatably lock the internal gears of the at least two stages when the one-way clutch does not transmit rotation, and to rotate the internal gears of the at least two stages when the one-way clutch transmits rotation. The at least two stages include a speed-increasing planetary gear mechanism and a speed-reducing planetary gear mechanism.

An electric power tool includes an electric motor with a motor gear, an output shaft with an input gear, a coupling that connects the motor gear to the input gear, and a housing that houses the motor, the motor gear, the coupling and the input gear. The coupling includes a shaft portion and two connective portions arranged at opposite ends of the shaft portion for connection to the motor gear and input gear, respectively. The motor gear and the input gear, each, have a cambered profile allowing a tilting movement of the coupling with respect to an axial position of one of the motor gear and the input gear that has a cambered profile.

An electric motor-driven screwdriver includes a control circuit having a memory stored with setting data and a computing unit controlling the electric motor-driven screwdriver based on the setting data. The computing unit sets an execution order of work processes based on a pre-designated piece of order setting data, and sets, based on a next operation setting value, a next operation to be performed after completion of the final work process. The next operation setting value is selectable from among a setting value for stopping the operation of the electric motor-driven screwdriver, a setting value for repeating a series of work processes, and a setting value for shifting to a series of work processes in an execution order determined based on another piece of order setting data.

An electric portable power tool, having a housing, a shaft, a control cam, an electric drive accommodated in the housing to drive the drive shaft, and an output unit that is positively connected with the drive via a mechanical shut-off clutch to transfer torque from the drive to an insertion tool connected with the output unit. The mechanical shut-off clutch comprises a control ring that is axially mounted against the force of the return spring and at least one switch element that is run on the control cam. The control cam is delimited at one end by a first switching contour for providing a release torque of the shut-off clutch and by a boundary contour at another end. The control cam is associated with a second switching contour for providing a pre-torque which is less than the release torque.

A power tool is provided with a tool housing, a support plate provided within the tool housing, a rear tool cap mounted on a rear end of the tool housing, and a brushless direct-current (BLDC) motor received within the housing. The motor includes a stator assembly having a stator core and stator windings, a front motor bearing supported by the support plate, a rear motor bearing supported by the rear tool cap, and a rotor including a rotor core and a magnet ring mounted around the rotor core. The rotor core defines an annular recess within which at portion of the front bearing and a portion of the support plate are located such that the a radial plane intersects the front bearing, the magnet ring, and the stator core.

An electric power tool in one aspect of the present disclosure includes a motor, an impact mechanism, and a control circuit. The control circuit executes a motor control process. The motor control process includes limiting an output of the motor in response to establishment of a preset condition. The preset condition is based on a load applied to the motor.

The drill includes a motor, a spindle rotatable with a rotational force transmitted from the motor, a clutch assembly that disables transmission of the rotational force to the spindle in response to a rotational load on the spindle reaching a release value and including an elastic member that adjusts the release value, and a change ring switchable from a clutch mode in which the clutch assembly is operable to a nonclutch mode in which the clutch assembly is inoperable in response to the change ring operated in a forward rotation direction. In the clutch mode, the elastic member elastically deforms to reduce the release value in response to the change ring operated in the forward rotation direction, and to increase the release value in response to the change ring operated in a backward rotation direction.

An electric working machine may include an output shaft, a rotary blade attached to the output shaft, an output pulley fixed to the output shaft, an input shaft, an input pulley fixed to the input shaft, a transmission belt wrapped around the input pulley and the output pulley, an electric motor including a motor shaft and configured to rotate the motor shaft, a speed reducer configured to reduce a speed of rotation of the motor shaft and transmit the rotation to the input shaft, and a housing that houses the electric motor and the speed reducer, and rotatably supports the input shaft and the output shaft. A rotation axis of the motor shaft may be inclined with respect to a direction which is along a rotation axis of the output shaft.

A power tool device, in particular a screwing and/or drilling device, including a drive unit for a rotational driving of a tool, in particular a drill or a screwdriver blade. The power tool device is adapted to detect at least one drive variable (AG) during the rotational driving of the tool, in which the drive variable (AG) is the torque acting on the tool and/or a drive variable associated with this torque, for example an electrical drive variable of the drive unit. The power tool device is adapted to determine a change criterion during the rotational driving of the tool on the basis of the at least one detected drive variable (AG) and to change the rotational driving of the tool in response to the detected drive variable (AG) satisfying the change criterion.