Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Yuki Horie

Kazuhiko Funabashi

Yasushi Nakano

Nobuhiro Takano

Shinji Watanabe

Hirohisa Tomita

Haruhisa Fujisawa

Takao Aradachi

Yoshikazu Kawano

Yukihiro Shima

Takuya Yoshinari

Hiromi Ozawa

Yuta Noguchi

Miyoji Onose

Yuuichi Toyoshima

Provided is an electric device, power device, electric device system, and management device capable of providing a theft prevention function that requires less effort as compared to the prior art. A power tool comprises a main power tool unit, and a battery packwhich can be attached to and removed from the main power tool unit. The main power tool unit and the battery pack each have a storage means for storing at least one authentication code and a communication means for transmitting and receiving the authentication code, and permit use when an authentication code received via the communication means matches at least one of the authentication codes stored in the storage means, and do not permit use when said authentication code does not match any of the authentication codes. The authentication code is set by a management device which is an external device.

Electric device, power device, electric device system, and management device

In order to enable easy determination of whether a battery pack possessed by a user is one to be guaranteed or not and clearly differentiate an old battery pack from a new battery pack not to allow the old battery pack to be used in the field, when a battery diagnosis device determines that the battery pack is one to be guaranteed, information held by the diagnosed battery pack is written into a second battery pack different from the diagnosed battery pack.

Battery diagnosis device and battery pack

A power tool includes: a secondary battery; a drive unit; a detecting unit; and a control unit. The secondary battery has positive and negative terminals across which a battery voltage is developed. The drive unit is connected to the secondary battery. The detecting unit is configured to detect a current value and a voltage value supplied from the secondary battery to the drive unit. The control unit is configured to control an effective voltage and an effective current applied to the drive unit depending on a load imposed thereon to fall within an allowable power dissipation value.

Power tool

A power-supplying device includes a terminal, a rechargeable battery, a first shutdown circuit, and a second shutdown circuit. The terminal is configured to be connected to a power tool. The rechargeable battery is configured to output electrical power to the power tool via the terminal. The first shutdown circuit is positioned at a plus side of the rechargeable battery, the first shutdown circuit being configured to shutdown output of the rechargeable battery. The second shutdown circuit is positioned at a minus side of the rechargeable battery. The second shutdown circuit is configured to shutdown output of the rechargeable battery.

Power-supplying device

An electric working machine including: a motor; a control unit configured to control rotation of the motor; a fixed part provided with a handle having a grip portion; a movable part held by the fixed part and is configured to be extendible by sliding relative to the fixed part; and a cutting blade provided to a end portion of the movable pipe and is configured to be driven by the motor; characterized in that the electric working machine further includes a detection unit which is connected to the control unit and is configured to detect whether or not the movable part is positioned at a predetermined extended position relative to the fixed part.

Electric working machine

An electric working machine including: a motor; a driving unit configured to be driven by the motor; a trigger switch configured to allow rotation of the motor; a power supply unit configured to supply electric power to the motor; and a control unit configured to control rotation of the motor, characterized in that: the electric working machine further comprises a switching element configured to perform short-circuiting between terminals of the motor to apply electronic braking, wherein the control unit is configured to perform adjustment of the braking by controlling the switching element when stopping the motor.

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

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.

Growing community of inventors

Ibaraki, Japan

Yuki Horie