A hand-held power tool is disclosed with a measuring system for determining an effective value of an alternating voltage which is fed via an external conductor with respect to a neutral conductor. A regulated direct voltage source has a power supply potential which is referenced to the neutral conductor. There is a first resistance value from the power supply potential to a tap and a second resistance value from the tap to a ground. A voltmeter has a measurement range and its measurement input is connected to the tap. A measurement line connects the tap to the external conductor. The first resistance value is lower than the second resistance value such that the mean voltage value on the tap is equal to the mean of the measurement range for one period of the alternating voltage.

A leveling device assembly for use with a hydraulic hammer is provided. The leveling device assembly comprises a control unit, a leveling sensor in communication with the control unit, and a laser generator in communication with the control unit. Additionally, the laser generator is configured to produce a first colored light beam and a second colored light beam different from the first colored light beam. The control unit is further configured to cause the laser generator to produce the first colored light beam when the leveling sensor indicates the hydraulic hammer is in a substantially vertical position and produce the second colored light beam when the leveling sensor indicates the hydraulic hammer is in a substantially non-vertical 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.

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.

Illustrative embodiments of impact tools with impact mechanisms rigidly coupled to electric motors are disclosed. In at least one illustrative embodiment, an impact tool may comprise an impact mechanism, an electric motor, and a control circuit. The impact mechanism may comprise a hammer and an anvil, the hammer being configured to rotate about a first axis and to periodically impact the anvil to drive rotation of the anvil about the first axis. The electric motor may comprise a rotor that is rigidly coupled to the impact mechanism, the electric motor being configured to drive rotation of the hammer about the first axis. The control circuit may be configured to supply a current to the electric motor and to prevent the current from exceeding a threshold in response to the hammer impacting the anvil.

A signal processing apparatus for a tool including a rotating body rotated by impacts delivered from a drive apparatus is provided with: a filter a calculation circuit and a control circuit. The filter receives a torque value signal indicating a torque applied to the rotating body, and filters the torque value signal. The calculation circuit sets a filter coefficient of the filter based on a number of impacts delivered to the rotating body. The control circuit controls the impacts delivered to the rotating body, based on the torque value signal filtered by the filter.

A percussion tool, for performing a chiseling operation on a workpiece with a chisel, comprises a housing including a front side, and rear side, and opposite lateral sides extending between the front and rear sides, a first handle coupled to a first of the lateral sides of the housing, a second handle coupled to a second of the lateral sides of the housing, the first and second handles oriented coaxially along a handle axis, an electric motor positioned within the housing, a percussion mechanism driven by the motor and including a striker supported for reciprocation relative to the housing along a striker axis, and a light source that produces light to illuminate the workpiece. The chisel is configured to deliver repeated axial impacts to the workpiece in response to receiving repeated axial impacts from the striker.

An impact tool comprises: a casing; a rotating hammer arranged in the casing and rotatable by a motor; a rotating interface element arranged in the casing and rotatable by the hammer by a series of impacts; an output shaft rotating around a rotation axis, the output shaft having a proximal end fixed to the interface element and a distal end protruding from the casing, the distal end ending with a connecting element for removable connection to an outer mechanical adaptor; a unit of measurement arranged for obtaining torque of the output shaft by a torque sensor mounted to the output shaft, the unit of measurement comprising a fixed measuring assembly mounted integrally to the casing and a rotating measuring assembly mounted so as to rotate integrally with the rotating output shaft; the fixed measuring assembly being configured to generate a supply signal and transmit the supply signal to the rotating measuring assembly to supply electrically the rotating measuring assembly; the rotating measuring assembly being configured to detect a measuring signal indicating the torque and condition the measuring signal in order to be able to send the measuring signal to the fixed measuring assembly; in which the fixed measuring assembly and the rotating measuring assembly comprise electronic devices that execute a two-directional communication in contactless mode by magnetic coupling between the fixed measuring assembly and the rotating measuring assembly, the communication being configured to supply magnetically the torque sensor and permit transmission of the measuring signal conditioned by the rotating measuring assembly to the fixed measuring assembly.

A power tool includes a housing, a motor received in the housing, an output driven by the motor, and a control system. The control system includes a rotational motion sensor configured to generate a rotational motion signal that corresponds to a rotational motion of the housing about an axis, a current sensor configured to generate a motor current signal that corresponds to an amount of current drawn by the motor, and a control circuit that is configured to receive the rotational motion signal and the motor current signal and to control operation of the motor. The control circuit is configured: (a) to determine, based on the current signal, whether a detected kickback condition is likely to be false; (b) to determine, based upon the rotational motion signal, whether an uncontrolled kickback condition has occurred; and (c) to initiate one or more protective operations upon determining that an uncontrolled kickback condition has occurred and is not likely to be false.

A method for sensing at least one characteristic value of at least one tool, in particular a hand-held power tool, includes detachably connecting the tool to at least one additional module and detecting with the additional module at least one characteristic value of the tool. The method further includes carrying out at least one training operation. The training operation includes deriving at least one reference value from the at least one characteristic value via the additional module and storing the reference value.