A power tool is provided including a brushless direct-current (BLDC) electric motor having a stator and a rotor. The power tool includes power switches including high-side switches and low-side switches disposed on a direct-current (DC) bus line between a power supply and the electric motor, and a controller configured to electronically brake the motor by simultaneously closing the high-side switches or the low-side switches to electrically short the stator windings. In an embodiment, the controller is configured to monitor a voltage of the DC bus line, and if the voltage of the DC bus line is lower than a voltage threshold, execute electronic braking by toggling between closing the high-side switches and closing the low-side switches over braking cycles, and if the voltage of the DC bus line is greater than the voltage threshold, execute braking by closing only the high-side switches or the low-side switches over the braking cycles.

A power tool includes a motor including a rotation shaft; an output shaft to which a cutting blade is attachable; a belt for transmitting a rotational force of the rotation shaft to the output shaft; an intermediate shaft positioned between the rotation shaft and the output shaft on a transmission path of the rotational force; a plurality of pulleys including a first pulley provided on the rotation shaft and rotatable integrally with the rotation shaft and a second pulley through which the intermediate shaft is inserted and having a diameter greater than that of the first pulley, the first pulley and the second pulley supporting the belt and being rotatable in accordance with rotation of the rotation shaft; and a transmission restricting part provided on a transmission path for transmitting rotation of the second pulley to the cutting blade and configured to interrupt or limit transmission of a rotational force.

An angle guide assembly for being coupled to a table body that slides along a longitudinal axis relative to a base of a saw. The angle guide assembly includes an attachment member configured to attach the angle guide assembly to the table body; a guide body and an angled fence pivotally coupled to the guide body between a first orientation in which a workpiece can be placed at an angle to the longitudinal axis along a first guide surface of the guide body by placing the workpiece against the fence surface, and a second orientation in which a workpiece can be placed at an angle to the longitudinal axis along a second guide surface of the guide body by placing the workpiece against the fence surface.

A machine tool includes a tool and a protective device. The tool includes a saw blade and a motor for driving the saw blade. An insulating member is arranged between the saw blade and the motor. The protective device includes a signal receiving unit, a control unit and a breaker. The signal receiving unit has an antenna receiving end that is in electrical contact with a middle region of the saw blade. The breaker is electrically connected between the motor and a utility power supply. The control unit is connected to the signal receiving unit and the breaker. The saw blade is used as an antenna by the signal receiving unit to receive an electromagnetic wave having the same frequency as that of a utility power from an environment, and the control unit controls the breaker according to a change of intensity in the electromagnetic wave.

A machine tool includes a tool and a protective device. The tool includes a saw blade and a motor for driving the saw blade. An insulating member is arranged between the saw blade and the motor. The protective device includes a signal receiving unit, a control unit and a breaker. The signal receiving unit has an antenna receiving end that is in electrical contact with a middle region of the saw blade. The breaker is electrically connected between the motor and a utility power supply. The control unit is connected to the signal receiving unit and the breaker. The saw blade is used as an antenna by the signal receiving unit to receive an electromagnetic wave having the same frequency as that of a utility power from an environment, and the control unit controls the breaker according to a change of intensity in the electromagnetic wave.

A handheld power tool with a rotatable tool, in which the handheld power tool is a saw blade or milling cutter. The handheld power tool includes a sensor device for detecting a mechanical vector quantity. The mechanical vector quantity includes a force, an acceleration, a velocity, a deflection, a deformation and/or a mechanical stress and the mechanical vector quantity depends on a force emanating from the handheld tool. The handheld power tool also includes a control device which is communicatively coupled to the sensor device and is adapted to recognize an event and/or a state of the power tool according to a direction and/or change of direction of the mechanical vector quantity detected by the sensor device.

A portable handheld machine saw having a saw assembly (11) which has a saw tool receptacle (14) for a saw tool (15) and a saw drive motor (12) for driving the saw tool receptacle (14), and having a guide device (17) which has a guide body (18) having a guide surface (19) extending along a longitudinal axis (L) for guiding the handheld machine saw (10) in a working direction (AR) on a workpiece (W). The handheld machine saw (10) has a pre-scoring assembly (31), arranged in front of the saw assembly (11) on the guide device (17) in relation to the working direction (AR), having a pre-scoring tool receptacle (34) for a pre-scoring tool (35), and having a pre-scoring drive (32A), for driving the pre-scoring tool receptacle (34), wherein, on the basis of the pre-scoring tool (35) protruding in front of the guide surface (19) during pre-scoring operation of the handheld machine tool, a score (RI) can be introduced into the workpiece (W), in the working direction (AR), in front of the saw cut (SAE) to be introduced.

The disclosure relates to a brake device for an electric motor, which has at least one armature winding and at least one field winding, comprising at least one open-loop and/or closed-loop control unit at least for open-loop control and/or closed-loop control of at least one electric current through the armature winding and/or through the field winding. According to the disclosure, in the event of short-circuit braking of the electric motor, the open-loop and/or control-loop unit is intended to reduce, at least temporarily, an electric armature current flowing through the armature winding.

A method of detecting and mitigating kickback in a saw includes identification of a running average speed (RPM) of a saw blade, the speed at a given time sample relative to the running average speed, the percentage change in speed from one speed sample to the previous speed sample, and the percentage change in average speed based on the current speed of the saw blade. If the identified speed profile from the samples indicates a kickback is imminent, then the saw identifies an imminent kickback event and removes power from the saw motor to mitigate kickback.

A method of detecting and mitigating kickback in a saw includes identification of a running average speed (RPM) of a saw blade, the speed at a given time sample relative to the running average speed, the percentage change in speed from one speed sample to the previous speed sample, and the percentage change in average speed based on the current speed of the saw blade. If the identified speed profile from the samples indicates a kickback is imminent, then the saw identifies an imminent kickback event and removes power from the saw motor to mitigate kickback.