Abstract: An electric power tool includes a body part for outputting a rotational force at one end thereof, a grip part provided to extend from the body part in an intersecting relationship with the body part, and a suspension link provided at the other end of the body part for hanging the body part. The suspension link is configured to ensure that, if the body part is suspended from the suspension link using the suspension link as a pivot point, the electric power tool is kept by a weight balance in a horizontal posture in which the extension direction of the grip part is substantially orthogonal to the vertical direction or an inclined horizontal posture in which the joint portion of the body part and the grip part is positioned at the upper side.

Abstract: An electric power tool includes a motor, a speed reduction mechanism, a power output unit, a control circuit unit, and a housing. The housing provided with an air supply-exhaust hole. The motor includes a stator core wound with coils, a rotor core and an electronic circuit unit. The electronic circuit unit includes a circuit board, electronic components arranged in the circuit board and including a switching element, coil connection portions arranged in the circuit board and connected to the coils and a control circuit connection portion arranged in the circuit board and connected to the control circuit unit. The motor further includes a radiator member for dissipating heat generated in the switching element of the electronic circuit unit and an insulating cover member molded to cover the electronic components, the coil connection portions, the control circuit connection portion, the circuit board and the radiator member.

Abstract: A charging circuit includes a battery pack provided with one or more secondary batteries and a battery charger for charging the secondary batteries, the battery pack being detachably attachable to the battery charger. The charging circuit further includes a control unit for performing a charging control, a monitoring unit for detecting charged voltage of the secondary batteries to determine completion of charging, a storage unit storing charging data for use in the charging control of the control unit and determination of the charging completion of the monitoring unit and a changing unit for changing the charging data. The monitoring unit and the storage unit are arranged in the battery pack, and the changing unit and the control unit are arranged in the battery charger.

Abstract: A battery pack which is detachably connected to a charger and charged by connecting thereto, includes a battery assembly including a plurality of secondary batteries serially connected; a pair of power terminals connected to a negative and a positive electrode of the battery assembly, respectively; a control circuit adapted to individually detect voltages across respective secondary batteries and output a charge control signal to the charger when the detected voltages exceed a predetermined value; a signal terminal adapted to output the charge control signal to the charger; and a temperature measurement element for detecting a temperature of the battery assembly. Further, the control circuit changes the predetermined value to be compared with the detected voltages based on the detected temperature of the temperature measurement element.

Abstract: A charger for an electric power tool includes a charging unit for charging a secondary battery detachably attached to the charger; a notification unit for notifying an operation state of the charging unit by using a combination of a turn-on and turn-off of the notification unit; a brightness reducing unit for reducing a light brightness of the notification unit; and a controller for controlling the notification unit and the brightness reducing unit. If an operation state of the charging unit satisfies a specific condition, the controller controls the brightness reducing unit to reduce the light brightness of the notification unit.

Abstract: A wireless communications system includes a tool having a first wireless communications unit and a transceiver having a second wireless communications unit to receive a signal transmitted from the first wireless communications unit. Further, the transceiver has a setting unit for setting wireless communications parameters for wireless communications between the first and the second wireless communications unit, and the tool has a tool control unit for setting in the wireless communications unit the wireless communications parameters set by the setting unit and transmitted to the tool by wireless communication.

Abstract: A charging controller connected to at least one of secondary cells and detachably connected to a charger or a cell driver, the charging controller including: a charging amount control circuit detecting a cell voltage of each secondary cell and outputting a charging control signal for instructing the charger to reduce a charging current when the detected cell voltage exceeds the target voltage; and a protection circuit detecting a cell voltage of each secondary cell and cutting off a current path from the charger to the secondary cell when the detected cell voltage exceeds the upper limit voltage, the protection circuit operating by using the secondary cell as a power source while at least the charger is not connected. In the charging controller, while neither the charger nor the cell driver are connected, the charging amount control circuit does not operate.

Abstract: A rotary impact tool includes a drive power source for producing rotational power, a drive shaft driven by the rotational power supplied from the drive power source, an output shaft operatively connected to the drive shaft for receiving the rotational power, an impact mechanism operatively couplable with the drive shaft. The rotary impact tool further includes a changeover unit for changing over an impact mode in which the impact mechanism is operated and a drill driver mode in which the rotational power produced by the drive power source is transferred to the output shaft without operating the impact mechanism and a multi-stage speed reduction mechanism for transferring the rotational power produced by the drive power source to the output shaft through the drive shaft at variable speeds in at least three speed modes including a low speed mode, a middle speed mode and a high speed mode.

Abstract: A changeover operation device, for changing over the positions of at least two components to establish three or more speed modes in a speed changer mechanism accommodated within a housing having an opening, includes operation handles arranged in a corresponding relationship with the components. Each of the operation handles is movable between two specified positions along a specified operation direction to change over the positions of the components. The operation handles are continuously arranged within the opening of the housing, one of the operation handles being partially overlapped with the other.

Abstract: A rechargeable electric power tool includes a motor driven by a secondary battery, a switching element for regulating power distribution to the motor, a motor control unit for controlling rotation of the motor through the switching element, a lead wire for supplying a drive current to the motor therethrough and a trigger switch changed over by a user for turning on or off the drive current supplied to the motor through the lead wire. In the rechargeable electric power tool, upon changeover of the trigger switch, a microcomputer determines a magnitude relation between a detected temperature outputted from a first thermistor and a first temperature threshold value. If the detected temperature is determined to be greater than the first temperature threshold value, the microcomputer is set in a limited operation mode in which a revolution number of the motor is limited to a predetermined value or less.

Abstract: In a rechargeable electric power tool, upon changeover of a trigger switch, a microcomputer determines the magnitude relation between the detected temperature outputted from the first thermistor and the first temperature threshold value, the second temperature threshold value and the third temperature threshold value, and the magnitude relation between the first calculated temperature increase rate and the first preset temperature increase rate. If the detected temperature is determined to be greater than the first temperature threshold value or if the first calculated temperature increase rate is determined to be greater than the first preset temperature increase rate after the detected temperature has been determined to be greater than the second temperature threshold value, the microcomputer is set in a limited operation mode in which the revolution number of the motor is limited to a predetermined value or less.