Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Koki Holdings Kabushiki Kaisha

Katsuhiro Oomori

Chikai Yoshimizu

Masato Sakai

Masanori Watanabe

Yoshihiro Komuro

Nobuhiro Takano

Takuya Teranishi

Kazutaka Iwata

Takuma Saito

Tomomasa Nishikawa

Kazuhiko Funabashi

Shinki Ohtsu

Takeshi Matsuoka

Kenichirou Yoshida

Hiroki Uchida

Mizuho Nakamura

Hironori Mashiko

Takeshi Taniguchi

Shinichi Sakamoto

Atsushi Nakagawa

Tomoyoshi Yokota

Yutaka Ito

Hidekazu Harada

Tadayoshi Mineta

Kenichi Kato

Hideyuki Tanimoto

Hiroyuki Hanawa

Yasuki Ohmori

Junichi Toukairin

Naoki Tadokoro

Hayato Yamaguchi

Toshiyuki Nemoto

Saroma Nakano

Masanori Okada

Hideki Ishida

Yoshitaka Suzuki

Shinji Watanabe

Masayuki Ogura

Takashi Ozawa

Takuhiro Murakami

Hitoshi Tsuzuki

Takeshi Takeda

Kiyoshi Kato

Hiroto Inagawa

Hideyuki Hashimoto

Junichi Kamimura

Junichi Tokairin

Shigeru Takahashi

Akira Oono

Kousei Yokoyama

Atsushi Sumi

Tomoyuki Hoshi

Yasuyuki Ooe

An electronic pulse driver includes a motor, a hammer, an anvil, an end tool mounting unit, a power supply unit, and a control unit. The hammer is rotatable together with the anvil. The end tool mounting unit transmits the rotation of the anvil to an end tool. The power supply unit supplies a drive electric power to the motor. The control unit controls the power supply unit to halt a supply of the drive electric power to the motor when an electric current flowing to the motor increases to a prescribed value. The control unit controls the power supply unit to supply to the motor a prestart electric power lower than the drive electric power before supplying the drive electric power in order to permit the power supply unit to supply the drive electric power after the hammer is in contact with the anvil.

Power tool

According to an aspect of the present invention, there is provided an impact tool including: a motor; a hammer connected to an output portion of the motor; and an anvil to be struck by the hammer in a rotation direction and having a rotary shaft, the hammer striking the anvil in the rotation direction by driving the motor in pulses, wherein the anvil is provided in front of the hammer, wherein the hammer is driven in pulses by the motor, and wherein a rotation angle of the hammer is substantially proportional to a rotation angle of the motor.

Impact tool

According to an aspect of the invention, an electric power tool which includes a brushless direct-current motor and a drive circuit that supplies drive power to the motor, and which rotates or drives a tool, characterized in that the drive circuit includes plural switching elements, and is arranged on a board provided in a grip portion of a housing or below the grip portion; and an electric fan is provided in the vicinity of the switching element for cooling the switching element.

Electric power tool

An impact tool () includes a motor (); a hammer () having a rotational axis extending in a first direction, the hammer () being rotatable in a rotational direction including a forward direction and a reverse direction opposite to the forward direction by the motor () and being movable in the first direction and a second direction opposite to the first direction; an anvil () disposed at the first direction side of the hammer () and strikable by the hammer () in the forward direction, the hammer () that has been struck the anvil () being moved in the second direction to come free from the anvil (); and a fixing member (A,A) that selectively allows the hammer () to move in the second direction or prevents the hammer () from moving in the second direction.

A power tool includes a housing, a brushless motor, and a cover member. The housing has an air intake hole and an air exhaust hole formed therein, the housing having an inner surface. The brushless motor has an outer surface disposed in the housing, a first endface near the air intake hole, and a second endface near the air exhaust hole. The cover member covers at least one of the first endface and the second endface for preventing dust from entering the brushless motor. The inner surface of the housing and outer surface of the brushless motor define a circulation path providing communication between the air intake hole and the air exhaust hole.

According to an aspect of the present invention, there is provided an impact tool including: a motor drivable in an intermittent driving mode; a hammer connected to the motor; an anvil to be struck by the hammer to thereby rotate/strike a tip tool; and a control unit that controls a rotation of the motor by switching a driving pulse supplied to the motor in accordance with a load applied onto the tip tool.

An electric tool including: a motor having a stator coil; and a circuit board, wherein the stator coil includes a coil main body and an extending part extending from the coil main body and electrically connected to the circuit board, and wherein the extending part is slacked.

Electric tool

According to an aspect of the present invention, there is provided a power tool including: a brushless motor; switching elements that drive the brushless motor; a circuit board on which the switching elements are mounted; a transmission portion that transmits a driving force of the brushless motor; and a housing that houses the brushless motor, the switching elements, the circuit board and the transmission portion therein, wherein the switching elements include semiconductor elements each having terminals on a bottom surface thereof, and wherein the switching elements are surface mounted on the circuit board.

An electric power tool () includes a brushless direct-current motor () and a drive circuit that supplies drive power to the motor, the power tool rotates or drives a tool, whereby the drive circuit includes plural switching elements (), and is arranged on a board () provided in a grip portion of a housing or below the grip portion; and an electric fan () is provided in the vicinity of the switching element for cooling the switching element.

A battery device is constituted by connecting such cell assemblies in parallel as each includes: a first cell group having a plurality of cells connected in series; a housing container for housing the first cell group; current detector housed in the container for detecting a current to flow through the first cell group; a switching element connected with the first cell group for turning ON/OFF the current to flow through the first cell group; and a controller for controlling the ON/OFF of the switching element in response to the output signal of the current detector.

Battery pack and cordless tool using the same

A power tool includes a body housing a motor and a power transmission mechanism positioned ahead of the motor for transmitting a power of the motor, a handle grip having an upper end portion connected to an approximately intermediate portion of the body and a lower end portion to which a battery is connected, a light emitting element positioned below the power transmission mechanism and receiving electrical power from the battery for illuminating a portion ahead of the body, and a trigger positioned below the power transmission mechanism for controlling a supply of the electrical power from the battery to the motor and to the light emitting element.

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.

Cordless power tool and battery device used for same

Growing community of inventors

Ibaraki, Japan

Katsuhiro Oomori