Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Chikai Yoshimizu

Katsuhiro Oomori

Masanori Watanabe

Nobuhiro Takano

Kazuhiko Funabashi

Masato Sakai

Shinki Ohtsu

Hideyuki Tanimoto

Eiji Nakayama

Atsushi Nakagawa

Takeshi Matsuoka

Takuya Teranishi

Takuma Saito

Shinichi Sakamoto

Hiroyuki Oda

Tomoyoshi Yokota

Hiromi Ozawa

Hidekazu Harada

Satoru Matsuno

Takahiko Shimada

Tadayoshi Mineta

Kenichi Kato

Tomomasa Nishikawa

Yasuki Ohmori

Shigeru Shinohara

Yoshikazu Kawano

Yoshihiro Komuro

Hiroaki Orikasa

Masateru Niyada

Kenro Ishimaru

Yuuichi Konuma

Toshiyuki Nemoto

Takeshi Taniguchi

Takashi Ueda

Kazutaka Iwata

Hiroyuki Hanawa

Yoshihiro Nakano

Hiroki Uchida

Mizuho Nakamura

Hironori Mashiko

Yuichiro Sasaki

Hayato Yamaguchi

Tetsuhiro Harada

Toshihito Sakaba

Saroma Nakano

Jyunichi Suzuki

Junichi Konishi

Toshiaki Mashiko

Mikio Kitao

Kazuhisa Hashimoto

Masao Kikumoto

Yasusi Anzo

Kouichirou Yamada

Nobuaki Hatanaka

Kihatirou Matsumoto

Yoshihiro Hoshi

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

Electric operating machine

The sealing property obtained when a battery pack is attached to an electric power tool is improved. An electric power tool to/from which a battery pack retaining a battery cell is attachable/detachable has: a tool main body being provided with an attachment part to/from which the battery pack is attached/detached; a guide groove which is provided in the attachment part and which determines a direction of the attachment/detachment of the battery pack; a device-side terminal which is provided in the attachment part and which is connected to a battery-side terminal provided in the battery pack; and a seal member which is provided in the attachment part and which seals a connecting part between the battery-side terminal and the device-side terminal.

Electric device including sealing member between attachment part and battery pack

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

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

Work machine and brushless motor

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.

Adaptor, assembly of battery pack and adaptor, and electric tool with the same

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.

Electric motor having an output shaft rotatably supported by a housing and working machine including 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.

Power tool

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.

A power tool includes a motor as a drive power source, a body housing the motor and having an end output unit for chucking an end tool, a handle grip connected to the body; and a light unit disposed to one of the handle grip and the body, and having a light-emitting element for providing illumination near the end tool. The light unit comprises switch means for switching the light-emitting element on and off, and an off circuit for automatically turning the light-emitting element off at a predetermined time after the light-emitting element turns on.

Power tool with light unit

An electric fastener driver having a compact size and simple construction. A driver segment provided with a rack is movably disposed in a housing. A flywheel is driven by a motor. A drive shaft is concentric with and integral with the flywheel. A coil spring is fixed to the drive shaft. A driven rotor is coaxial with the drive shaft and has one end portion serving as a spring seat portion positioned within the coil spring. A pinion is disposed at the driven rotor and is meshedly engaged with the rack. An urging section is disposed within the driven rotor. A ball is movably disposed in a through-hole formed in the driven rotor for urging an end portion of the coil spring by the urging section. A solenoid controls a protruding amount of the ball from the surface of the driven rotor.

Electrically driven flywheel-fastener driver

A cover which covers outer peripheries of fastening screws are disposed on an outer periphery of a hammer case. A stopper which detachably positions and fixes the cover to the outer periphery of the hammer case is disposed.

Electric power tool

Electric power tool with cover

In order to prevent a battery pack from being overly discharged during use in a power tool, a discharge voltage limit circuit is provided. The circuit disconnects the battery pack from the motor when the voltage of the battery pack falls below a predetermined level. However, the circuit is operable only when the main switch is OFF, that is, when no load is imposed on the motor.

Battery-powered tool capable of detecting discharged battery pack

A commutator motor includes a stator and a rotor, and the stator includes a stator yoke and a field magnet. The field magnet is fixed onto the inner peripheral surface of the substantially cylindrical stator yoke. The stator yoke is configured by coaxially stacking a plurality of plate-like annular bodies, and the annular bodies are fixedly connected to each other by caulking at a caulking portion disposed on the annular body. In manufacture, the length of the stator yoke in the axial direction can be arbitrarily changed with the thickness of the annular body in the axial direction as a minimum unit. In case of manufacturing various stator yokes that are different in the axial length, the necessity of replacing a manufacturing machine is eliminated, thereby providing a commutator motor having the stator yoke which is low in the manufacturing costs.

Commutator motor

A power tool includes a hook portion having a hook holding portion, which is provided in a housing and has engaging teeth provided in the housing. A hook having a shaft portion is inserted into the hook holding portion and provided with fitting teeth meshing with the engaging teeth An elastic body is adapted to push the hook against a handle portion at all times, and a slip-off preventing part holding portion is adapted to move the hook in a direction of an axis thereof against a force of the elastic body and to cancel the mesh between the teeth to thereby enable the hook to turn.

Growing community of inventors

Hitachinaka, Japan

Chikai Yoshimizu