Abstract: A charging signal Vi responding to a charging current is inputted to one input terminal (?) of an operational amplifier 95 forming a comparator and a setting signal Vr corresponding to a setting current value is inputted to the other input terminal (+) of the operational amplifier 95. When the charging signal Vi is not higher than the setting signal Vr, a charging stop signal is generated from the output terminal of the operational amplifier 95 to interrupt a switch unit 4. A starting signal Vcc larger than the setting signal Vr applied to the other input terminal (+) is applied to the one input terminal (?) of the operational amplifier 95 through a condenser 94 till a prescribed time elapses from the start of a charging operation to generate a charging start signal from the output terminal of the operational amplifier 95 and electrically conduct the switch unit 4.

Abstract: A power tool is connectable to a battery pack including a secondary battery. The power tool includes a motor and a prohibiting unit. The motor is driven with an electrical power supplied from the secondary battery. The prohibiting unit prohibits the supply of the electrical power to the motor based on a drop amount of a voltage of the secondary battery.

Abstract: An electric operating machine comprising a motor and a power circuit driving the motor by the electric power supplied from a battery. The power circuit comprises a voltage conversion part converting an input voltage entered in accordance with a voltage of said battery to generate an output voltage and outputting said generated output voltage to said motor. The power circuit is structured so that the voltage value of said output voltage of said voltage conversion part is changeable.

Abstract: A charging apparatus able to safely and reliably secure capacity is provided. The charging apparatus comprises: a charging current configuration unit that configures a set value for the charging current flowing to the battery; a charging current controller that controls the charging current on the basis of the set value configured by the charging current configuration unit; a cell voltage detector that detects the cell voltages applied to each cell; and a voltage determining unit that determines whether or not at least one of the cell voltages detected by the cell voltage detector has exceeded a threshold voltage. If it is determined by the voltage determining unit that at least one of the cell voltages has exceeded the threshold voltage, then the charging current configuration unit switches the set value to a smaller value.

Abstract: When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.

Abstract: The power circuit comprises a voltage conversion part converting an input voltage entered in accordance with a voltage of a power source to generate an output voltage and outputting the generated output voltage to the motor and a current detection part outputting a first signal in accordance with a current flowing through a given part of the power circuit. The voltage conversion part lowers the voltage value of new output voltage being generated when the current detection part outputs the first signal.

Abstract: When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. The voltage from the battery pack is detected. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.

Abstract: For a lithium battery pack including battery cells the number of which is larger than the number of battery cells 111 that can be monitored by a voltage detect portion 115, there is disposed a temperature detect element 113 for detecting the temperatures of the battery cell 112 not monitored by the voltage detect portion 115, and, when the temperatures of the battery cell 112 detected by the temperature detect element 113 rise beyond a given value, there is issued a signal to stop the charging of the battery pack.

Abstract: A power tool, having attached thereto a battery device including one or a plurality of cell assemblies, includes a motor which is supplied with a DC current from the battery device, a switching element which controls a drive and a stop of the motor, means which detects a number of cell assemblies, and control means which controls the switching element in such a way as to stop the drive of the motor when the number of cell assemblies is smaller than a prescribed value.

Abstract: When a main switch (12) is turned ON, an electric operating machine (1) is put in the standby mode. With a trigger (13) being pulled in the standby mode, a power supply circuit (16) applies a voltage to a drive part (30). The power supply circuit (16) adjusts the voltage applied to the drive part (30) for a voltage corresponding to the pulling rate of the trigger (13). When the current running toward the drive part (30) exceeds the rated value of the drive part (30), the power supply circuit (16) automatically stops power supply to the drive part (30). On the other hand, when the output voltage of a battery (50) drops and the battery (50) is put in an overdischarge state, power supply to the drive part (30) is automatically stopped. When it is detected that the battery (50) undergoes an abnormal event, power supply to the drive part (30) is automatically stopped.

Abstract: In a battery pack which comprises: a battery set composed of two or more lithium battery cells connected in series; a first protection circuit including a first voltage detect part for detecting the voltage(s) of a part of the two or more battery cells, and a first signal output part for issuing an output signal when a detect voltage detected by the first voltage detect part goes below a given over-discharge judgment voltage value; a second protection circuit including a second voltage detect part for detecting the voltage(s) of another part of the two or more battery cells, and a second signal out part for issuing an output signal when the detect voltage of the battery cell detected by the second voltage detect part goes below a given over-discharge judgment voltage value; and, a switch which is connected to the current path of the battery set and can be turned on or off according to the output signals of the first and second signal output parts and, there is further provided dead time means connected betwee

Abstract: A motor has an output shaft which is rotatably supported by a housing, a rotor which is fixed to the output shaft and which comprises a printed-wiring board, and a stator which is fixed to the housing and which comprises a magnet facing the rotor. The printed-wiring board comprises a coil/commutator disk and a coil disk. A commutator conductor pattern is formed in a commutator region of the coil/commutator disk. Likewise, coil conductor patterns are formed in respective coil regions of the coil/commutator disk and of the coil disk.

Abstract: An electric grasscutter includes a motor (50) which drives a rotary blade (42). The motor (50) is a brushless motor accommodated in a motor housing (51) and including a rotor (53) provided integrally with an output shaft (52), and a stator (54) fixed to the motor housing (51). A motor control circuit which drives the motor (50) is accommodated in the motor housing (51). The motor control circuit includes an inverter having FETs (81-86) as switching elements, and a control section to control the FETs (81-86). The FETs (81-86) are fixed in contact with the motor housing (51).

Abstract: An electrical power tool includes a motor, a load detecting unit, a trigger switch, and a power supplying unit. The load detecting unit detects a load applied to the motor. The trigger switch receives an instruction. The power supplying unit starts supplying of a driving electrical power to the motor when the trigger switch receives the instruction. The power supplying unit changes an amount of the driving electrical power based on the load detected by the load detecting unit.

Abstract: A charging system has a battery pack and a charging device. The battery pack has a battery cell and a plurality of identifiers that identify a configuration of the battery cell. The charging device has a charging unit, a signal transmission unit, a reading unit, and a control unit. The charging unit charges the battery pack. The signal transmission unit transmits a first signal and a second signal to the battery pack separately to read the plurality of identifiers when the battery pack is attached to the charging unit. The reading unit reads the plurality of identifiers according to the first and second signals to determine the configuration of the battery cell. The control unit controls the charging unit according to the configuration of the battery cell.

Abstract: A compact battery pack with high handling ability and restraining degradation of battery cells. The battery pack includes an insertion portion to be inserted into a handle portion of a cordless power tool and an accommodation portion in which all battery cells are accommodatable. A protection board with a protection circuit that protects batteries against overcharge and over-discharge is installed in the insertion portion. A switching element is connected between the battery cells and a drive motor of the power tool. An air passage in communication with the battery pack is formed within the handle and a main housing of the cordless power tool. The switching element is positioned at the air passage.

Abstract: A setting current switching circuit 120 includes a comparator 127. A battery temperature signal corresponding to a battery temperature detected by a battery temperature detecting unit 8 is inputted to one input terminal (?) of the comparator 127 and a reference signal corresponding to a reference temperature is inputted to the other input terminal (+) of the comparator 127 to vary the setting charging current value of a charging current setting unit 80 and the setting full-charge current value of a full-charge current setting unit 90 correspondingly to the output of the comparator 127.

Abstract: A power tool 1 is connected to a battery pack 5 including an overcurrent detector 533 which detects overcurrent of a battery module 51 and outputs a detection signal, and an overdischarge detector 532 which detects overdischarge of the battery module 51 and outputs a detection signal. The power tool 1 includes a motor 2 which is driven by electric power supplied from the battery pack 5, a trigger switch 31 for setting the power supply from the battery pack 5 to the motor 2 in ON/OFF state, and an FET 410 which sets the power supply to the motor 2 in ON/OFF state on the basis of the detection signal from the overcurrent detector 533 or the overdischarge detector 532.

Abstract: To prevent a battery pack from being over-discharged even under a state that the battery pack (a secondary battery) is connected to a discharging device that is not connected to an ac input power source for a long time. A charging device has a pair of output lines and an anode terminal and a cathode terminal of a secondary battery electrically connected between the output lines to carry out a charging operation. In the charging device including a component circuit part electrically connected by traversing a part between the pair of output lines, a switching element is inserted between the component circuit part and one of the pair of output lines. When the charging device is not connected to an input power source, the switching element is allowed to be non-conductive to interrupt a discharging path so that the component circuit part does not form the discharging path.

Abstract: A compact battery pack with high handling ability and restraining degradation of battery cells. The battery pack includes an insertion portion to be inserted into a handle portion of a cordless power tool and an accommodation portion in which all battery cells are accommodatable. A protection board with a protection circuit that protects batteries against overcharge and over-discharge is installed in the insertion portion. A switching element is connected between the battery cells and a drive motor of the power tool. An air passage in communication with the battery pack is formed within the handle and a main housing of the cordless power tool. The switching element is positioned at the air passage.