Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Shinji Watanabe

Kazuhiko Funabashi

Yasushi Nakano

Nobuhiro Takano

Masahiro Inaniwa

Hiroyuki Hanawa

Tomomasa Nishikawa

Katsuhiro Oomori

Noriyasu Matsufuji

Takuhiro Murakami

Masayuki Ogura

Takahiro Fujimaki

Haruhisa Fujisawa

Takao Aradachi

Junichi Toukairin

Toshio Mizoguchi

Takuya Teranishi

Shota Kanno

Shota Takeuchi

Osamu Kawanobe

Nobuharu Kido

Yusuke Funabiki

Junpei Sato

Hikaru Tamura

Kazutaka Iwata

Akira Matsushita

Eiji Nakayama

Yoshikazu Kawano

Hayato Yamaguchi

Katsunori Akatsu

Yoshinori Tobita

Yuki Horie

Masaru Hirano

Naoto Wakatabe

Kenichirou Yoshida

Yukihiro Shima

Takafumi Itoh

Yoshitaka Niinai

Hideki Watanabe

Miyoji Onose

Satoshi Numata

Takayuki Watahiki

Tsutomu Takamura

Norihide Tao

The electrical apparatus, in which a series connection state and a parallel connection state of an upper cell unit including five battery cells and a lower cell unit can be automatically switched by means of a difference in a terminal shape on the electrical apparatus body side, has a terminal holder and holds apparatus side terminals. The terminal holder, which establishes an electrically connected state with the connection terminals of the battery pack, is provided with two parallel protruding parts that extend in the forward-backward direction, and second rail grooves fitted to the protruding parts on the electrical apparatus side. Due to the fitting, relative movement of the terminal holder and the battery pack in the vertical direction can be suppressed, and wear on the apparatus side terminals can be greatly suppressed.

Electrical apparatus using battery pack

A battery pack houses first and second cell units that are composed of a plurality of cells, and has a positive electrode power source terminal and a negative electrode power source terminal. This battery pack is provided with a series connector capable of connecting, in series, the first and second cell units and a parallel connector capable of connecting, in parallel, the first and second cell units, and is capable of switching between a parallel connection voltage and a series connection voltage. In the case of attachment to the high voltage electrical device body, the series connector becomes conductive and the parallel connector pair is cut off by the action of the series/parallel switching terminal. In the case of attachment to a low voltage electrical device body, the state is returned to an initial state, the series connector is cut off, and the parallel connector pair becomes conductive.

Battery pack, electrical device using battery pack, and electrical device system

In an upper cell unit () and a lower cell unit () comprising five battery cells, positive electrode terminals () are set apart and aligned vertically, and negative electrode terminals () are set apart and aligned vertically. When an electrical device body is rated at 36V, device-side terminals are in contact only at the upper terminals (), and short circuiting of the lower terminals () is effected using a short bar. When the electrical device body is rated at 18V, the upper and lower terminals (andand) are simultaneously made to contact the device-side terminals, and the upper cell unit () and the lower cell unit () assume a parallel connected state. Thus, it is possible to automatically switch the output voltage when a battery pack is mounted according to the difference in terminal shape on the electrical device body side.

A power supply device includes a main body, a cover member, a rechargeable battery, and an inverter device. The main body is configured of box-shape formed with an opening. The cover member is configured to open and close the opening. The rechargeable battery is accommodated in the main body. The inverter device is configured to be accommodated in the main body. The inverter device converts a direct voltage from the battery to an alternating voltage and outputs the alternating voltage.

Power supply device

A power tool system includes: a power tool including an AC motor; a portable battery pack; and a power supply device that converts a DC power supplied from the portable battery pack into an AC power to supply the AC power to the AC motor.

Power tool system and power supply device

A current detection circuit () detects that a drive current of the stator coil () is exceeding a threshold value Ir. A rotation number detection circuit () detects that the number of rotations of a rotor () is lower than a threshold value Nr. A computing part () outputs a PWM signal which switches a semiconductor switching element () of the inverter circuit part (). The computing part () changes the threshold values Ir and Nr in accordance with the PWM duty of the PWM signal determined in accordance with a pressed distance of a switch trigger () and detects a locked state of the motor () on the conditions that the motor current I is exceeding the set threshold value Ir and that the number of rotations N thereof is lower than the threshold value Nr.

Electric rotating tool

An inverter device includes: an inverter circuit configured to perform ON/OFF operations with a preset duty cycle to convert a DC power into an AC power and output the AC power to an AC motor; and a controller configured to change a duty cycle of the ON/OFF operations.

Inverter device and electric power tool

An impact tool () includes a spindle (), a motor (), a rotational impact system (), a current detecting unit (), and a current control unit (). The spindle extends in an axial direction thereof. The motor provides the spindle with a rotational power in accordance with a motor current flowing therethrough. The rotational power rotates the spindle about the axis at an rpm value. The rotational impact system provides the spindle with an impact force in the axial direction, thereby transmitting both the rotational power and the impact force to an end bit. The current detecting unit detects a current value of the motor current. The current control unit reduces the current value if the current value detected by the current detecting unit exceeds a predetermined value.

Impact tool

A setting current switching circuitincludes a comparator. A battery temperature signal corresponding to a battery temperature detected by a battery temperature detecting unitis inputted to one input terminal (&#x2212;) of the comparatorand a reference signal corresponding to a reference temperature is inputted to the other input terminal (+) of the comparatorto vary the setting charging current value of a charging current setting unitand the setting full-charge current value of a full-charge current setting unitcorrespondingly to the output of the comparator

Battery charger

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.

Charging device having protective switching element

Abnormal detecting meansfor detecting that an electrically conductive foreign substance has migrated into a charging deviceis provided, and whether or the foreign substance has migrated is judged from the detection result of the abnormal detecting means

Charging device for battery

A battery charger is configured to use selective one of two or more power supplies including a commercial AC power supply and a DC power supply. An AC cable is fixedly secured to the body of the battery charger and a DC cable is detachably connected to the body of the battery charger. A single transformer is employed that has a first primary winding to which the AC power supply is connected a first switching element, a second primary winding to which the DC power supply is connected via a second switching element, and a secondary winding to which a battery pack to be charged is coupled.

Battery charger operable for selective one of a plurality of power supplies

A power toolis connected to a battery packincluding an overcurrent detectorwhich detects overcurrent of a battery moduleand outputs a detection signal, and an overdischarge detectorwhich detects overdischarge of the battery moduleand outputs a detection signal. The power toolincludes a motorwhich is driven by electric power supplied from the battery pack, a trigger switchfor setting the power supply from the battery packto the motorin ON/OFF state, and an FETwhich sets the power supply to the motorin ON/OFF state on the basis of the detection signal from the overcurrent detectoror the overdischarge detector

Power tool

In a charging device, a driving power supply circuit for driving a control circuit is formed as a separate system from a first power supply circuit, regardless of whether the first power supply circuit is in a driving state or a non-driving state. A microcomputer alternately and intermittently controls the first power supply circuit in the driving state or the non-driving state when the battery pack is not mounted in the charging device in order to reduce the potential difference between the battery pack and the output voltage of the first power supply circuit, thereby avoiding an excessive discharge current from the battery pack when the battery pack is mounted in the charging device.

Secondary battery charging device

Growing community of inventors

Hitachinaka, Japan

Shinji Watanabe