A system is provided with a set of removable battery packs and a set of power tools each including a motor, a controller, and a battery receiving portion. For each power tool, the controller is configured to identify a type of battery pack coupled to the battery receiving portion and set a conduction band associated with phases of the motor or an advance angle by which phases of the motor are shifted based on the identified type of the battery pack.

A power tool has highly airtight electrical connection between a controller and a switch to effectively prevent a short circuit. A grinder includes a housing, a motor accommodated in the housing, a controller accommodated in the housing and including a circuit board and a controller terminal located on a first facing surface and electrically connected to the circuit board, a switch accommodated in the housing and including a switch terminal located on a second facing surface facing the controller, being in direct contact with the controller terminal, and electrically connected to the controller terminal, and a seal located between the first facing surface and the second facing surface and sealing a periphery of the controller terminal and a periphery of the switch terminal with the controller terminal being in direct contact with the switch terminal. The first facing surface is a surface of the controller facing the switch.

An electric work machine (1) includes a motor (8) having a rotor (23) disposed within a stator core (31) and coils (34) disposed on the stator core; a power-transmission mechanism (10) driven by the rotor; and an output shaft (6), on which a tool accessory is mountable and which is operably driven by the power-transmission mechanism. The stator core includes an outer-side member (40) having projection parts (42) protruding radially inward from a circular-ring part (41) in a spaced apart manner in a circumferential direction of the stator core and respectively supporting the coils; and an inner-side member (43) disposed radially inward of the outer-side member and coupled to inner-end portions of the projection parts. A plurality of first insulators (32) and a plurality of second insulators (33) may be respectively disposed around the projection parts and interconnected in an alternating manner in the circumferential direction.

A power tool and a safety control circuit module and a safety control method thereof are provided. The power tool includes a power supply device, a control processing device, a safety control circuit module, and a power output device. The control processing device is electrically connected with the power supply device. The safety control circuit module includes a first switch control circuit, a second switch control circuit, a third switch control circuit, a first resistor, and a first diode. The power output device includes a first power connection terminal and a second power connection terminal. Before switch units of the control circuits are controlled, the control processing device detects whether the switch unit has failed, so as to increase safety.

Kickback control methods for power tools. One power tool includes a movement sensor configured to measure an angular velocity of the housing of the power tool, and an orientation sensor configured to measure an orientation of the housing. The power tool includes an electronic processor coupled to a switching network and a trigger. To implement the kickback control, the electronic processor is configured to receive measurements of the angular velocity of the housing, receive measurements of the orientation of the housing, determine a binding condition of the power tool based on the measurements of the angular velocity and the measurements of orientation, and control the switching network to cease driving of the brushless DC motor.

A method operates an electrical treatment device having a user-operable operating switch, and a motor electronics system with a motor control and an electric drive motor. The switch electrically connects to a drive voltage source and the motor electronics system. The motor electronics system electrically connects to the drive motor on an output side via the motor control. The method monitors whether an input voltage at the motor electronics system meets a closed criterion or an open criterion, wherein the closed criterion is characteristic of a closed switching state of the operating switch, and wherein the open criterion is characteristic of an open switching state of the operating switch, and when the open criterion is met, operates the motor control in a state from an open state set that includes a voltage control state for limiting an increase in the input voltage caused by the running-down electric drive motor.

A motor controller for a motor having an end cap. The motor controller including a power board adapted to couple with a first surface of the end cap, on an internal side of the motor, and including opposing first and second sides and a control board adapted to couple to a second surface of the end cap, on an external side of the motor, and including a processor. The power board including position sensors disposed on the first side and switching elements disposed on the second side.

A brushless motor includes a stator and a rotor rotatably received within the stator, the rotor including a rotor shaft, a rotor body mounted on the rotor shaft and including axial slots, permanent magnets disposed within the axial slots, and a rotor end cap provided at an end of the rotor body to axially retain the permanent magnets within the slots. The rotor end cap includes an outer planar portion that is in contact with the end of the rotor body, and ribs angularly extending from the outer planar portion towards a center portion forming openings therebetween to allow passage of air between adjacent openings in thermal contact with the end of the rotor body.

A controller of a power tool outputs a driving signal to a motor driving circuit and acquires a position of a rotor of a brushless motor. While acquiring the position of the rotor of the brushless motor, a phase voltage or a line voltage of a winding of the brushless motor is detected through the voltage detection circuit. Whether an upper bridge arm switching element, a lower bridge arm switching element, and/or the brushless motor is short-circuited is determined according to the phase voltage or the line voltage of the winding of the brushless motor.

A power tool (1), such as an impact wrench (1), includes: a brushless motor (8); a motor housing (7), which houses the brushless motor (8); an anvil (4), which is rotationally driven by the brushless motor (8) and disposed forward of the brushless motor (8); a handle (3), which is disposed downward of the motor housing (7); a battery-mount part (5), which is disposed downward of the handle (3); a battery pack (6), which is mounted on the battery-mount part (5) by being slid relative to the battery-holding housing (5); and a controller (70) for controlling the brushless motor (8). A switch panel (73) having at least one manipulatable button (73c) and at least one display part is provided downward of the handle (3) and is tilted such that the switch panel (73) is higher in the front.