Abstract: A hand-held power tool includes a motor having a stator and a rotor, the motor being configured to rotate the rotor at a speed of at least 40,000 rpm, an output shaft directly driven by the rotor, a tool accessory shaft configured to support a tool accessory, and a two-stage speed reducing transmission operably connecting the output shaft to the tool accessory shaft. The two-stage speed reducing transmission is configured to drive the tool accessory shaft at a rate less than the rotor speed, for example, at a rate less than or equal to 37.5% of the rotor speed.

Abstract: In a motor control circuit, a switching element such as an FET for controlling a motor current and a current detection element for detecting the motor current are connected in series. One terminal of a temperature detection element is electrically connected to an electrical connecting section between the FET and the current detection element, and the other terminal of the temperature detection element is electrically connected to a temperature detection circuit.

Abstract: A power tool according to one aspect of one embodiment described in the disclosure includes a brushless motor, a battery voltage detection unit configured to detect a voltage of a battery that provides energy for driving the brushless motor, a rotational position detection unit configured to detect a rotational position of the brushless motor, and a control unit configured to control a drive output supplied to the brushless motor based at least in part on a signal from the rotational position detection unit. The control unit controls a current conduction angle and/or an advance angle supplied to the brushless motor so that, during control of the drive output to the brushless motor, a rotational speed or a conducting current of the brushless motor approaches or reaches a target value, the target value being based at least in part on a battery voltage detected by the battery voltage detection unit.

Abstract: A motor driven appliance comprises a battery, a motor, at least one switch, a control unit, an abnormality detection unit, a determination unit, and a processing unit. The at least one switch comprises an operation switch. The control unit controls driving of the motor by controlling power supply from the battery to the motor when the operation switch is turned on. The abnormality detection unit detects abnormality of the appliance. The determination unit determines whether the detected abnormality is a first type abnormality that can be cleared when the operation switch is switched from on to off, or is a second type abnormality that cannot be cleared even if the operation switch is merely switched from on to off. The processing unit is configured to perform a specific process when it is determined that the detected abnormality is the second type abnormality.

Abstract: In an electric power tool which houses a motor and a controller for controlling drive of the motor, the controller has a circuit board on which electric components are mounted and a heat radiation member which radiates heat of the electric components. The heat radiation member has a facing part which faces the circuit board in parallel to a board surface of the circuit board. The facing part is provided with steps by which a distance between the facing part and the board surface of the circuit board varies. Furthermore, the facing part of the heat radiation member is provided with a first facing part in which a relative distance with respect to the board surface of the circuit board is reduced.

Abstract: An electric power tool according to the present invention is provided with a tool main body, an induction motor, a power supply unit, and an inverter. The power supply unit and the inverter are integrally incorporated in the tool main body together with the induction motor.

Abstract: An electric power tool is provided with a three-phase brushless motor that drives a tool and a motor driver that drives the three-phase brushless motor with square voltage waves. The motor driver is able to set a conduction angle to a value that is equal to or more than 130 degrees but not more than 180 degrees, and especially to change the conduction angle among at least two values that are equal to or more than 130 degrees but not more than 180 degrees. In this configuration, it may be preferable that the conduction angle is set to a larger value as a load applied to the tool becomes smaller. On the other hand, it may be also preferable that the conduction angle is set to a larger value as a load applied to the tool becomes smaller.

Abstract: A motor driven appliance in one aspect of embodiments of the present disclosure comprises a light source, a lighting unit, a motor, an operation unit, an operation detector, a reference signal output unit, a determination unit, and a control unit. The operation detector detects that the operation unit is operated, and outputs an operation detection signal that indicates that the operation unit is operated. The reference signal output unit outputs at least one reference signal that can be used as a reference for determining whether the detection by the operation detector is normal. The determination unit determines whether the operation unit is actually operated based on the operation detection signal and the at least one reference signal. The control unit controls operation of the lighting unit based on the determination made by the determination unit.

Abstract: A hand-held power tool includes a motor having a stator and a rotor, the motor being configured to rotate the rotor at a speed of at least 40,000 rpm, an output shaft directly driven by the rotor, a tool accessory shaft configured to support a tool accessory, and a two-stage speed reducing transmission operably connecting the output shaft to the tool accessory shaft. The two-stage speed reducing transmission is configured to drive the tool accessory shaft at a rate less than the rotor speed, for example, at a rate less than or equal to 37.5% of the rotor speed.

Abstract: A motor current detection apparatus in the present invention includes: a current detection unit, a first filter, and a second filter. The detection unit detects a conduction current flowing from a battery to a brushless motor and outputs a conduction current signal corresponding to the detected conduction current. The first filter extracts a first current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a frequency band equal to or lower than a predetermined first cutoff frequency. The second filter extracts a second current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a predetermined frequency band within a frequency band equal to or lower than a predetermined second cutoff frequency higher than the first cutoff frequency and having the second cutoff frequency as a maximum value.

Abstract: A power tool according to one aspect of one embodiment described in the disclosure includes a brushless motor, a battery voltage detection unit configured to detect a voltage of a battery that provides energy for driving the brushless motor, a rotational position detection unit configured to detect a rotational position of the brushless motor, and a control unit configured to control a drive output supplied to the brushless motor based at least in part on a signal from the rotational position detection unit. The control unit controls a current conduction angle and/or an advance angle supplied to the brushless motor so that, during control of the drive output to the brushless motor, a rotational speed or a conducting current of the brushless motor approaches or reaches a target value, the target value being based at least in part on a battery voltage detected by the battery voltage detection unit.

Abstract: In a motor control circuit, a switching element such as an FET for controlling a motor current and a current detection element for detecting the motor current are connected in series. One terminal of a temperature detection element is electrically connected to an electrical connecting section between the FET and the current detection element, and the other terminal of the temperature detection element is electrically connected to a temperature detection circuit.

Abstract: An electric power tool is provided with a three-phase brushless motor that drives a tool and a motor driver that drives the three-phase brushless motor with square voltage waves. The motor driver is able to set a conduction angle to a value that is equal to or more than 130 degrees but not more than 180 degrees, and especially to change the conduction angle among at least two values that are equal to or more than 130 degrees but not more than 180 degrees. In this configuration, it may be preferable that the conduction angle is set to a larger value as a load applied to the tool becomes smaller. On the other hand, it may be also preferable that the conduction angle is set to a larger value as a load applied to the tool becomes smaller.

Abstract: A rechargeable electric power tool includes a battery pack that is detachably provided on a housing accommodating a motor and that supplies electric power to the motor, and a tool that is driven by the motor. A standby switch and a lock-on switch are arranged at the housing. The standby switch is able to set the rechargeable electric power tool to a standby state where the rechargeable electric power tool waits for the motor to be driven. The lock-on switch is able to shift the rechargeable electric power tool from the standby state to a state where the motor is driven so as to keep the state where the motor is driven.

Abstract: A motor current detection apparatus in the present invention includes: a current detection unit, a first filter, and a second filter. The detection unit detects a conduction current flowing from a battery to a brushless motor and outputs a conduction current signal corresponding to the detected conduction current. The first filter extracts a first current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a frequency band equal to or lower than a predetermined first cutoff frequency. The second filter extracts a second current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a predetermined frequency band within a frequency band equal to or lower than a predetermined second cutoff frequency higher than the first cutoff frequency and having the second cutoff frequency as a maximum value.

Abstract: A cordless electric power tool comprises a motor that drives a tool, a battery that supply electric power to the motor and a motor drive circuit that is disposed between the motor and the battery. The motor is a three-phase brushless motor, and the battery has a nominal voltage of 18 volts. An overall electric efficiency of the cordless electric power tool becomes at least 70 percent when a value of current passing through the motor becomes at least 35 amperes but no more than 45 amperes and the cordless electric power tool outputs power of at least 450 watts but no more than 550 watts.

Abstract: One aspect according to the present invention includes a power tool including a control device that can output a brake operation signal to a DC motor to apply a short-circuit brake thereto in response to turning off an operation switch. The brake operation signal is stopped depending on the rotational speed of the motor when the operation switch is turned off during the rotation of the DC motor.

Abstract: One aspect according to the present invention includes an electric power tool, in which a capacitor is positioned closer to a motor control circuit than a switch electrically connected to the motor control circuit.